Imperial Home Page -> Repair -> Transmission -> Shifting Problems
Question from Joel:
What components can cause a tranny to slip? We both suspect the torque converter (when I get on the gas, it stalls or takes a minute to tranfer the power). The slip seems to be getting worse. Will it affect the bottom end of the motor (crank)? It struggles in high gear now and bucks like I'm out of gas. If I accelerate continually it's fine but if I coast and try to accelerate, the motor just revs. I don't drive her much, .8 miles to the train station. I can either slowly increase speed to avoid slipping but I'd never get out of 1st (create a traffic jam) or I can mash it into the
higher gear but I'm sure that's only making it worse. It also looses all pull in a turn. I have to accelerate then coast through the turn.Reply from John:
It sounds like the fluid level is low.
Question from Remco (1957):
I have a problem with my Torqueflite. I put another transmission in the car and my new one was not used for 2 years. All forward gears work, neutral also works but reverse is not working. I have a big transmission oil cooler with a pressure gauge in the line and there is 45 to 55 psi pressure on this line all the time. When I put car in gear, the pressure drops a bit but it is back to 45 after 1 second or so. Can the regulator valve or the converter control valve be stuck and give this problem? I removed the accumulator spring as advised to get a firmer shift and reduced the weight of the governor weight and gave a bit more line pressure (1/2 a turn). Have these 3 things anything to do with the reverse? I was advised to do so because I am pulling a 6000 pound trailer.
Replies:
From John:
This may be a stupid question, but is the reverse button seated correctly on the fork? I've owned lots of push button Imperials & have had several instances where the buttons have become dislodged.
From Tony:
Have you checked the reverse band? These are made of cast iron and can snap easily. It happened to me last year.
From Marty:
I had this problem with my 1959 when I bought it back in 1987. The seals that sit the highest in the transmission are the seals for reverse. If the car sits for long periods of time without being started the seals for reverse never get any fluid and dry out. the transmission will most likely have to have the seals and a rebuild done. I might be wrong, but this fixed my problem, and has worked great for over 10 years.
From Eric:
I had this trouble last year in my '72 Newport. As I recall, the 'low / reverse shaft' broke. I was advised this is a common failure point at about 125-150k miles. I didn't do the work, though I did have an opportunity to look up in the gearbox to see a broken shaft while at the transmission shop. I still had 1st gear but no reverse, not sure what function this shaft performs.
From William:
The fluid pressure you're reading on the cooler line is "Lube Pressure". In my '67 Chrysler service manual, for example, it lists Lube Pressure in the schematics for the different gear selections as 5-30psi. "Line Pressure" is taken from a fitting on the right side of the transmission after removing a plug and attaching a pressure gauge (the 1957 version might be slightly different than the later aluminum case version, but still similar). Line pressure varies with the gear and mode of operation to well over 200psi in "R".
Removing the accumulator spring is a "standard" hot rod trick to get a little faster apply pressure in the particular circuit. Even the factory shift kits that Mopar Performance sells has that in the changes to make. Grinding the governor weights a little will give higher shift points in all gears and is another "time honored" thing to do in the absence of a factory high-performance governor unit--but going too far can up the shift points too much.
In the case of a line pressure adjustment just because you're towing a trailer, I would think that with no significant power increase, it might not be necessary unless it's a "band aid" fix for an aging trans that might need to be rebuilt anyway. For example, in many of the aftermarket hop up kits for the Dodge Cummins Diesel pickups, where massive power increases take place, they do recommend upping the Line Pressure due to the added power from the engine. Going the other way around with hauling more weight might not make it that necessary, it would seem to me.
Seems like I recall reading that many of the earlier TorqueFlites, even up to about 1965 or so in the aluminum case versions, that "Reverse" could have problems with not engaging all of the time. I'm not sure what the fix was, but it seems it was a valve body issue (maybe a shuttle valve spring?) of some sort. As mentioned, the linkage cable would need to be accurately relaying the "R" pushbutton command to the trans also.
In some cases, when automatic transmissions are stored, moisture from temperature changes in the storage area can cause valve body problems. The trans might be a good, working trans when it's pulled and placed on the floor, for example, but when it's reinstalled a few years later, it might have gear selection problems due to the deterioration/degradation of the valve body mating surfaces. In the case of a friend of mine with a GM Turbo 400, it worked when he got it rebuilt but when he installed it a year or so later, everytime it would shift into high gear, there was some bleedthru that also applied reverse with the same fluid pressure--instant trans brake. As he found out, such situations are somewhat common with used transmissions.
If shift firmness due to the heavier-duty activity is a perceived issue, then probably some different clutch plates and bands for the trans might be in order. Some that have a more agressive friction characteristics, for example, rather than the "smooth shift" factory style items. Not using "wavy" steel plates in the clutch packs will also result in slightly firmer and quicker shifts. The wavy steels were used in 1966 and later trans and if you know what you're feeling, there is a difference in the 1965 and 1966 TFlites--not sure if that's an issue with the earlier cast iron versions, though.
As for raising shift points, that can also be accomplished to a certain degree with the preload adjustment on the kickdown linkage. When we got our 1966 Chrysler, the shift points felt ok in normal driving, but I noted that if more throttle was used, the part throttle shift points seemed to lag until you put enough throttle to get a WOT kickdown situation. This was before the part-throttle kickdown came into play in the early 1970s.
What I found out was that if I shifted the trans manually on normal acceleration and delayed the shift points to a slightly higher speed, especially the 2-3 shift, I could accelerate faster with less throttle. I consulted with the service manager at the local Chrysler dealership and he mentioned that he put more preload into the linkage on his car to do just that for mountain driving. I filed that back for future reference.
When I took the car off to college, the traffic patterns in Lubbock moved faster than down here in the DFW area. Suddenly, I was one of the slow cars in the pack. Doing the manual upshift situation pretty much remedied that. In the case of the 1966 trans, the factory adjustment is 2 turns of preload on the kickdown linkage from hot, base idle. What I did was experiment and make the total 4 turns of preload instead of 2. That upped the part throttle and minimum throttle shift points so that I didn't have to manually shift any more. The car felt better as it took less throttle to do things in normal driving and was more fun to drive.
I also learned to do a version of the part-throttle kickdown manually too, basically emulating what the newer models did. Same result, less throttle and better acceleration without getting into the power mixture of the carb.
When we got the 1972 Chrysler, at the 3000 Mile Check-up, the mechanic tweaked the kickdown adjustment until it felt better and did not lug the motor quite so much at lower speeds. My shadetree guide is to have the car hit 3rd gear on light throttle at about 30mph (depending on the axle ratio, of course) so that rpm did not drop below 1000 rpm when that shift was completed.
When I got my 1980 Chrysler, it was also the victim of a too soon upshift (probably for the CAFE driving cycle). As the adjustment slot for the kickdown linkage was now under the car, I got two black cable ties and put them at the back end of the slot on the kickdown linkage at the carb. Worked fine. I've noticed that same "problem" with other Chrysler vehicles of the 1980s era too.
Many publications mention that you should not mess with the linkage adjustment from factory specs, but I've determined that a little tweaking does not really hurt anything. Basically, it's telling the trans that it has more throttle input that it reallly does, so it delays the upshifts as it "thinks" the driver needs more power and performance. Not lugging the engine on those early upshifts can also result in less heat being put into the trans fluid by the torque converter being in more of a torque multiplication mode. Just another little tweak that discretion must be used with so as to not get things out of whack.
In the case of the 55psi Lube Pressure, that seems a little high compared to the later models. Unless there are some high pressure rubber hose sections in that cooler line, the existing hose integrity could be compromised over a period of time. A failure in that area would not be something to desire, I suspect. You might desire to get a Chrysler factory service manual for that year vehicle to make sure that all fluid pressures are in spec. I also know that many trans shop techs have their own "secret fixes" for various upgrades too, which I respect, but I still might question sometimes.
Another "hot rod" trick for a firmer and quicker shift is to use the Type F trans fluid instead of Dexron variations or the earlier Type A. The "Ford Fluid" has a more agressive initial friction characteristic so the clutch pack/band engagement is firmer and quicker with less initial slippage. This was a somewhat common thing to do in the later 1960s and 1970s for both Chrylser and GM automatics.
Question from Philippe (1957):
My engine over-revs every time the transmission upshifts from 2 to 3. Only a 1/2 second but not a very good thing for the engine. It is more noticeable if the upshift occurs at a higher speed. When I look at the trasnmission power flow I note that when the transmission shifts from 2 to 3, there is a simultaneous disengagement of the KD band and an application of the rear clutch (front clutch remains engaged). It seems that on my car the two actions are not simultaneaous... Why? Is there a problem with the 2-3 shift valve or the "shuttle valve". Or anything else ?
Oil level is OK. Transmission has 4000 miles since overhaul. No slippage, no problems on 1-2 upshift.
Reply from Steve:
Check your adjustment on your throttle valve linkage-after you mentioned you didn't have a "kickdown" either, it's a real good chance that this linkage is out of adjustment. How is your 1-2 shift under normal acceleration? It should shift between 25 and 30 MPH. I'm guessing that it is a real quick shift which means your linkage travel is too short. The govenenor of the transmission will partially take over if the adjustment is off but your shifts won't be right.
Another way to check if it's the linkage or an internal trans problem is try manually shifting the trans. If your shift quality is better that way, you can almost be assured that the linkage is out of adjustment.
Question from Phillipe (1957):
For some weeks my car won't go in reverse but goes forward even in N !!
First you must know that:
- the transmission was completely and carefully rebuilt 6 years ago. It was not done by a tranny shop, but it was me with a friend.
- the transmission worked very well up to 1999. At this date there was a lot of brake problems on the car so the car wasn't driven between 1999 and 2001. I was too busy to rebuild the brakes. 6 months ago, the brakes were overhauled and the car was driven few miles.
But when I drove the car some weeks ago to a body shop (for paint work) I found a problem: there were some difficulties going into reverse: I had to run the engine at high rpm to engage the "R". After more tries, the car stopped engaging in "R" and at this time it began to run forward in N !!
This week I checked the car's transmission, and I thought it was a bad cable adjustment, a 10 minute job... We tried several different adjustments and the car doesn't go in "R" and continues to go forward in "N". But a problem occurred when we checked the oil level: the color of the oil was not the usual color but a "rusty" color and it seems that there was water in the oil. First we thought it was a leak in the radiator but the radiator coolant is perfect with no oil. The "taste" of the coolant is a sweet taste (permanent glycol antifreeze) but the transmission oil has not this sweet taste. So where does the water come from? Condensation? Long time of inactivity?
We removed the old "oil" from the transmission and converter and put fresh new oil in. Now the car goes forward in "N" and doesn't move in "R". The cable is perfectly adjusted (which was easy to check when the oil pan was removed). Then we removed the oil screen and found some small debris on it ... There's also a burnt smell on it ...I'll try to overhaul the valve body but I think that the clutches are out !!
Does someone has some ideas about this "water" the in transmission, assuming that isn't a leak from the radiator? And why the car drives in "N" with a correct cable adjustment?
Replies:
From Dick:
My guess would be that the low brake band is not releasing, probably because of some contamination in the valve body. It sounds like something has failed in a big way in the transmission. I think it needs to be rebuilt by someone with some experience with these transmissions. The rusty looking fluid is possibly contaminated fluid, perhaps with clutch material. This is typical of a failed rebuild.
From Steve:
My '59 does the same thing when in a bad mood. At worst I have to turn off the engine, restart, immediately go to reverse and then it will back up a few feet before it won't move at all anymore (at this point both reverse and drive are engaged basically stopping all movement).
I have been told by a couple of reputable trans guys that the internal seals are leaking and this is what causes the problem. Sounds like you are going to have to pull it out again.
Follow-up from Philippe:
I will probably overhaul my transmission. Here are some of the questions I received and will try to answer:
- You're right in assuming the clutches are the problem; they are seized together hence the drive in Neutral
- One of the clutch packs does not release
a) water has valve body stuck
b) water has swelled frictions or rusted steels locking clutch
I think this is the answer to the problem, according to the FSM transmission chart (about clutch pack: front clutches applied in all forward range / rear clutches applied in R and D / No clutches in N). When the transmission is in N, D, 1 or 2, the car goes forward but there's no upshift. Whichever you select a gear, the car runs at the same speed (and engine revved at the same rpm). I don't know if it's the 1st, 2nd or direct drive. I haven't driven the car very far (no R ..).
- If the car Locks up when put in reverse that means a clutch is not disengaging. Does it feel and sound like it goes into gear?
yes, the car is locked when the trans. is in R. Seems logical if front clutches remains applied. We can't push or pull the car with engine running . To push rearward the car we must stop the engine .. In R , engine revs free but trans. is locked !
- If you have water in the transmission oil it will turn into a pink milkshake. That is to say it looks white and cannot see through it
Difficult to describe the color of the fluid ! Isn't pink, it is completely unclear with a color between "rust" and "light chocolate". 2 or 3 persons who were in the shop agree that there is water in the fluid. We found some "creamy" mud on the valve body, cable housing etc..
- My guess would be the problem is a leak in the heat exchanger in the bottom of the radiator. When warmed up, there is greater pressure in the radiator than there is in the coolant lines and exchanger so the radiator solution enters the exchanger but trans fluid does not enter the radiator.
I'll take the radiator to a radiator shop to check it. The theory sounds good but when the engine is stopped, could the transmission fluid be contaminated by the coolant? And if there's a leak in the exchanger, the transmission fluid would be higher than normal. On the car the transmission fluid is at the correct mark.
Question from Philippe (1957):
My car drives in "R" only. My thought is that the cable is unhooked at the transmission end and the manual valve stays in "R" position, I can't see other reason. I rebuilt this transmission 1 year ago and I also reinstalled it in the car. Any ideas?
Replies:
From Kerry:
I thought the neutral safety switch would not allow the car to start in "R"?
Follow-up from Philippe:
Right! But I'm not sure the neutral safety switch is connected (perhaps the wire is grounded as I've seen on other MoPar cars with the starter switch on the "N" button). My mechanic tells me that the car is hard to push with the engine off. And as soon as he starts the car, a small pressure on the gas pedal drives the car in "R", no matter which button is engaged.
From Mark:
I bought a '76 Cordoba at an auction that drove forward in all gears. Only Park did not give forward movement. I suspect the tranny was fried and that's why it was auctioned. I don't think it was linkage because it went straight from Park to Drive, no Reverse or Neutral in between.
Update from Philippe:
I've looked at the car this morning:
- the trans. safety switch was wired but only at the transmission
- the cable was unhooked from the adapter at transmission
We remove the oil pan and saw that the manual valve stays in "R" if we pushed one of the buttons. So the problem with the cable, we discovered that the small spring on the control cable adapter was loose and it revolved 1/4 turn, so the vertical part of the spring was off the groove of the adapter and no longer blocked the cable, thus the cable was free! It happened when the transmission was in "R", so the transmission remains in "R" whichever button you engaged. The car could be started because the transmission neutral switch wasn't wired! Very dangerous indeed!!
Question from Remco (1957):
My '57 Torqueflite has a problem. When I start and than select reverse, it takes some time for it goes into gear. When I start and shift to drive, it only takes one second or so but to reverse, it takes longer. Sometimes I have to rev the engine a bit before gear will engage. The oil level seems to be ok. Do I need to have the transmission rebuilt or is there something else wrong? The oil is almost clear and doesn't smell burnt.
Replies:
From Asa:
If you have a good shift from 2nd into 3rd and high gear holds well, you most likely hard a faulty rear servo lip seal, which is passing the high pressure fluid by and not engaging reverse. If you don't fix the problem you'll eventually burn up the forward clutches!
From Philippe:
About shift 2-3: does the 3 engage ? If oil smells a bit burned it isn't a good sign and it isn't normal that the oil cooler lines remain cold; the oil flow to cooler is routed via the regulator valve and the converter valve. These two valves are on the side of trans (passenger side) at front. You'll find two large nuts one below the other. The upper is the converter valve, the lower (w/ adj. screw) is the regulator valve. If these valves are stuck, the oil flow is perhaps stopped. To remove these valves take a look at the FSM, it isn't very difficult except that there are often stuck. You must use a small drill (1/8" or 5/32") to remove the valves, they have a hole in the end for this purpose. Beware, valves are spring loaded ! Don't disturb the regulator valve adjust. screw, it's a factory setting. About the bands, I adjust mine with a classic torque wrench: the torque is 70 to 75 inch pounds (47 to 50 with the special tool C 3583). Then back off 2 5/8 turns on rear band and 2 1/4 turns on fwd band.
I've discovered that there are two plugs in the floor pan (on each side of the driveshaft "tunnel") which give access to the band screws. Pull the carpet and remove the plugs, it's easier than crawl under the car ..
From Marc:
The biggest enemy of any transmission aside from deliberate abuse is heat. Three years ago I had the 727 in my Coupe rebuilt and simultaneously had the largest stack plate transmission cooler B&M makes installed. After three scorching Texas summers and several 100+ mph runs down I-10 & I-45 the fluid still has the color of pink lemonade. The tranny still shifts the same, no slippy slide or mushy shifts.
Follow-up from Remco:
First to answer Philippe: yes 3th does engage. This morning I tried my car again... Firm shifts and no delay. I have to check if there is oil flow to the cooler. I did put the extra oil cooler inline with the original cooler. Is this too much restriction of the oil flow? Is it a good idea to take out the converter and the regulator valve clean and replace? I will chance the oil A.S.A.P and check for blocks in the lines. Any more ideas what can be wrong?
Reply from Brooks:
Don't forget to clean your screen.
Question from Richard (1960):
I have got the '60 LeBaron moving again, but it does so grudgingly. While I have not driven much over 100 feet, it seems to do just fine once in gear. I have to start the car, run it a few moments, and then push buttons and wait. Sometime waiting about 40 seconds or so before it responds, if it responds. Sometimes I wait, give it a little gas, and it will pop on, usually with a lurch due to my giving it gas. Reverse is the worst. Drive is poor going into gear, but ok. We discovered when rebuilding the top of the engine that the motor had been overhauled. The transmission is sprayed the same color so we know it too has been out of the car at some point. Now whether it was overhauled or not, I don't know. As I said, it seems to do fine once in gear, the fluid looks fine. We are considering adjusting the linkage cable/wheel. Has anyone ever had to do this? What were the results? &! nbsp;I just don't want to tinker with something if it is not likely the cause, though we think it is.
Replies:
From Steve:
This is a very common problem. I don�t know if it just with the cast iron trans or if it is caused by age of the seals. My opinion is that the seals in the trans are old and hard and it just takes a while for it to build up pressure and stop leaking. Some trans medic may help with the situation. The only cure I am aware of is to rebuild the transmission replacing all the seals. You might try changing the fluid and filter to see if it helps.
My �59 has been doing this since the day it came back to life four years ago. Only really caused me a problem once when I backed out on a busy street and then drive wouldn�t engage for something like two minutes (seemed like ten hours).
From Neal:
It will only get worse. My '59 would go into reverse with no problem, but what began as 10 or 15 seconds of idling before it would go into drive eventually became 10 minutes after about 2 years. The seals get hard and I was concerned that eventually I would get stranded somewhere. It got to the point that even after having the car sit for only a few hours at a car show, I would have to let it run for several minutes before it would move. I had the transmission rebuilt, with new seals, and now it works like it should.
From Kle:
Sorry to add to the chorus of bad news, but I agree it sounds like you need a rebuild. On the bright side, it should be fairly cheap ($400 - 800), and after it's done it ought to last you another 20 years.
From John:
I had to adjust the cable on my '60. I suspect this is what is wrong here, since that is just what my car was doing. You need to have someone hold the reverse button in while making the adjustment. I suggest getting a service manual & reading the instructions carefully & study the illustrations.
From Mike:
I believe the symptom you describe is caused from a worn pump bushing.
Question from Tim (1960):
I jacked the rear off the car up tonight after the test drive. It seemed that a brake was being applied when it shifts to a different gear. I jacked it up enough for the rear tires to clear the ground, about 2". The cars idles really nice when I engaged Drive. When the engine RPMs were raised it shifts to a different gear and it starts to bog down the engine. Just like a brake being applied on the drive shaft.
Replies:
From George:
Sounds like it is engaging 2 gears at once, try locking it in low and see what happens.
From Mikey:
Being that youre working on a pre '62 non aluminum case trans, I am delving into a bit of speculation here. When you are in Drive, you start out in first of course then when it upshifts into second the second gear band applies and I think its the rear clutch has to release. Otherwise you have two events trying to occur at the same time. What you feel as a bog is the clutch and band fighting each other, and that will wear one of them out.
Do you have a FSM for your car, you might want to check all the adjustments for shift linkage, kickdown linkage and all the external stuff. If you have had anything done lately then its a place to start, if its just come along out of the blue then I dont know if this will help but it would be a place to start and begin the process of elimination.
Question from Joe (1961):
I am in the process a purchasing a '61 Imperial. I talked with the owner this morning and in our discussion he proceeded to tell me that the motor runs but that the reverse gear doesn't work.
What could cause this problem? I have already heard the following suggestions: 1) the push button for reverse is not actuating the cam/control cable to shift in to reverse gear, 2) the reverse band could be broken (first & reverse are actuated by the same gear?), or 3) a valve body problem.
Any one of you have any suggestions on this? If it is one of the three suggestions above, what am I looking at in terms of a) fixing it myself, or b) the cost of repairs if done by a transmission mechanic.
Replies:
From Paul:
My experience has been that reverse goes out, and the rest of the unit follows shortly there after. As you say, it could be a linkage problem, but that has never been the case with me for this problem. I have three cars with that style transmission.
From Philippe:
1) The push button for reverse is not actuating the cam/control cable to shift into reverse. If the push button actuates the other gears, it must also actuates the R. Try to put the rear of the car on hoists and see if the wheels turn in reverse at normal speed.
2) The reverse band could be broken (first & reverse are actuated by the same gear). You need the R band in R but also in 1 position (not in the 1st of Drive or "breakaway"). If the 1 position is ok, it isn't the band.
3) A valve body problem. I think also at a rear clutch problem or a too low line pressure in R: the line pressure needed in R is twice the forward line pressure. I remember a car ('57 New Yorker) who has a lot of problem in R: the pressure was too low because the front pump was weakened. I It would be best to take the line pressure in D and in R (with the rear wheels off the ground).
From Tony:
One thing you have not mentioned but is also a possibility is a dislocated reverse band strut. This can be repaired without a complete teardown and rebuild but would need the the removal of the valve body to access the strut.
If I was buying this car, I would assume the worst and expect to have to rebuild the transmission. If you have to send it to a shop for repair, expect a hefty bill. This is an iron torqueflite and rebuild kits are not cheap. Bear in mind that once they open up a forty year old transmission they are likely to find other problems too.From John:
It could also be the shift cable is out of adjustment. Very likely if the trans has been serviced.
Question from John (1961):
Got a question about the torqueflite transmission. We have a lot problems with ours and maybe somebody would have some suggestions as what to do. I know the transmission needs to be rebuilt, but I can't do it at the moment. I've had the transmission drained and the pan dropped. The filter was solid with junk and that was replaced. A transmission cooler was also installed. Here is what the car does.
If you get in the car in the morning and start it up, it goes and shifts with no problems. Pull into any store and shut it off for 10 - 30 minutes and the car is stuck in first gear and either won't shift out of first at all or go about 10 miles or so and if I'm lucky the car will start shifting again. Even if the car shifts properly and you get it home and park it, the transmission will ooze out at least 2 bottles of transmission fluid overnight. I always keep a pan under the car due to the transmission. The engine is tight as a drum and doesn't leak a bit.Replies:
From Steve:
You could try a couple of bottles of trans medic. This would be a temporary fix at best buy I have seen it buy some transmissions a little more time.
From Dick:
This is probably caused by a piece of crud sticking in the governor. You can remove the governor yourself, and clean it out thoroughly, although you will need the shop manual for detailed directions. However, the fluid leakage means you are going to have to have the transmission gone through soon anyway, so why not bite the bullet and do it now?
Question from Dedy (1962):
My friend recently acquired 1962 Imperial LeBaron and he has a problem with the transmission. He described it as slipping/jumping. I wonder if he needs a new gearbox or perhaps a transmission overhaul kit will work?
Replies:
From Kerry:
It should not cost much to rebuild. I had mine rebuilt in my 73 (same innards) for $300 including a rebuild converter. I did the remove and re-install.
The shop manual describes symptoms and possible causes. It might just need a clean filter and new fluid or it might be shot. If he drops the pan to change the filter and there are aluminum particles in it, he most likely has a rebuild issue.
From Mike:
You might try checking the transmission fluid level. (idling in neutral of course)
From Christopher:
The problem may be related to the bands needing some adjustment. Usually, 2nd-3rd gear slips especially at a low cruising speed. The ultimate fix would be a shift kit to give make the shifts more decisive rather than soft, which is what reduces the wear and tear on the bands. You still may need to overhaul the transmission though, which you might as well do if you plan on installing a shift kit. Normally I'm a purist when it deals with keeping a car original, but on all of my Mopar cars over the years, that 727 has always been the achilles heel.
Question from Jim (1963):
When I put my '63 LeBaron into Park and the neutral switch kicks in, the car still rolls. Appearantly, Neutral works just fine. The transmission itself was rebuilt a few years ago. The archive was some help but I still couldn't find the source of the problem.
Reply from Mikey:
The aluminum case Torqueflite was introduced in '62. Basically with the minor exceptions of cable shift vs non cable shift, parking gear and rear pump the transmission was changed very little over the next several decades until the lock up converter came along and then the overdrive 518 trans.
As far as the post today about no reverse, a very likely culprit is the low-reverse band or the anchor for it. If the rest of the shifting is correct, check to see if it still works in manual Low - with the 1 button pushed in. If it does, then the band is applying. At that point the diagnosis gets a bit more complicated. It is still a very easy transmission to work on , as is any other aluminum case torqueflite.
There was another post about no parking gear, but the vehicle still rolled along as if it was in neutral. I would suspect the parking sprag or rod has a problem. This is a purely mechanical device that locks the output shaft when you put the car in park. They can and will break the parking lock off if someone has put the car into park at too high of a speed, or since the trans had been rebuilt, perhaps someone made an error.
Either way, a copy of Motors Automatic Transmission Overhaul ( the big book version, its kinda spendy ) or an ATSG ( Automatic Transmission Service Group ) or ATRA ( Automatic Transmission Rebuilders Association ) manual can get you all the pertinent info you need. The ATSG guides are probably 60 pages or so , written with the mechanic in mind, and are very reasonably priced.
Question from Allan (1964):
Is their anyone out there that can answer a question? I have a '64 Imperial Crown. The car sits most of the year. When the car is started from cold the carb kicks to high idle. If you try to put it in gear -- there's a lurching and it isn't happy with being in gear. Sometimes it just refuses to shift. This happens both in forward and reverse gear. If you let it warm up and kick it down to slow idle -- the car shifts buttery smooth. A trusted mechanic told me that this is a problem related to the age and that I only drive it about 500miles per year. He also stated that an additive is available that will cure this problem. Any suggestions?
Replies:
From Kerry:
I think most cars will do this. What happens is that over time, the fluid in the torque converter drains >back into the transmission itself and it takes a few minutes for the tranny to get itself in order. Also, most transmissions don't like dropping into gear from a high idle in neutral and will 'clunk' pretty hard. I've found that if my '64 has sat a while, if I let it idle in park for 60 seconds or so, blip the throttle to slow the idle, it does fine although there may be a little slippage for the first shift.
From James:
I've found on my '69 if after starting, I shift to neutral and let it run for 30 seconds or so to let the fluid re-circulate in the system, shifts will be normal.
From Elijah:
There's a very simple solution to this problem. Once the car is started, immediately shift it into neutral. This will refill the torque converter in just a few moments.
Allan, following this procedure will also help the "lurch" you are experiencing when shifting into gear. Let the fast idle run for a minute or two, and then tap the accelerator to step down to a lower idle. By this time, the torque converter will be "primed," and your idle will be low enough for a smooth shift.
Question from Ramon (1965):
Last night I took my '65 Imperial Crown for a spin, and when I put it in reverse to park, it got stuck. I found the shift cable broke off just inside the heat shield in the steering column. The car won't start now because it's not in 'park'. If anyone has any advice, please let me know what you think.
Replies:
From Teddy:
I think the '65 and '66 have the same gearshift linkage... the cable is just for the gearshift indicator. You should be able to change the gear by hand, using the linkage under the car. You will find it just under the driver's seat.
From Mike:
The 1965 models went to the Column shift BUT retained the CABLE shift Transmission of the PUSHBUTTON era. In 1966, they went to all linkage. In order for you to be able to start and move your Imperial, locate where the cable broke and see if you can get a
pair of vise grips or locking pliers on the innermost strand(s) of wire; I am hoping that you have at least an inch to play with. IF you do then move the cable all the way in and see if you can jazz the starter(keep your footon the brake for safety sakes!!!)IF not ,try pulling it out a little at a time, you may feel a click as it goes into each gear, when you hit neutral you can start it. THEN you can pull it out a little more until it goes into drive. At least you could then drive it to either your repairman or to your home( you did not say where you got stuck). BUT under no circumstances , DO NOT DRIVE it this way permanently. You will need to reolace the cable.!!!From Bill:
The 1965 Torqueflite did, indeed, retain the cable controls of the pushbutton era, but there are TWO cables on the transmission - one for park and one for all the other gears.
The one for R-N-D-2-1 is part number 2534 410 and is 44.96" long. Console shift A-727 models also used a 44.96" cable, but it is part number 2461 928. The park cable for an Imperial is number 2533 725. Both Imperial numbers were used only by Imperial and only in 1965.
These cables attach to the steering column at the base. They are attached to a plate that is attached to the steering column gearshift tube. It is this tube that the gearshift lever moves to activate the cables attached at the base. The cables themselves do not run up into the column.
There is, however, a cable the connects to the gear indicator (2660 119). This cable is attached to the gearshift lever at one end and the indicator at the other.
Question from Kevin (1971):
I started my '71 up, put it into reverse, stepped on the gas, and it felt like something snapped, or broke, or possible fell out of the tranny. Then
the car wouldn't go backwards, but it goes forward. I recently had the tranny re-built so I'm hoping Idon't need to re-build it again! Any suggestions?Replies:
From William:
I think your rebuild job is suspect.....low reverse band. Sorry to break the bad news.
From Rolland:
There are about three parts in the mechanical actuation of the reverse band that could be suspect. If you have a warranty take it back. If you need to repair it yourself remove the pan and carefully inspect the pivot arm that is actuated by the reverse servo. I have seen these castings break right off. It could also be that the link that connects the pivot arm to the reverse band came out of place. It could also be that the reverse band broke.
Some of these items you can repair with the transmission in the car. If it is a reverse band failure that will require removal.
From Kerry:
This is very similar to what happened to my '73 except I had the exact opposite action, i.e. would go in reverse but not forward. Anyway, there is a thingie that sticks out inside the case (called a sprag or sprang). This thing holds the gear assembly in place and allows it to work. No sprang, no move. There is something called a 'case saver' that allows the case to be salvaged but unfortunately it requires a removal of the trans and reinstall.
Ask your tranny guy if this is the same problem. I'd bet it is.
Question from Robin (1972):
On my '72 Imperial I have noticed a vacuum like noise if I shift to neutral. I did not know there was anything vacuum related linked to the shift mechanism. Anyone know what may be?
Replies:
From Chris:
It's your automatic parking-brake release, which is most likely leaking either at the diaphragm in the canister that's attached to the top of the parking brake pedal, or at the valve behind the regular brake pedal which opens when the gearshift is placed in R, D, 2 or 1 (if adjusted properly).
How to test if it's a problem: Put the car in Park. Set the parking brake. With the motor running, shift to R or D. The parking brake should release (sometimes this takes a few seconds). If the brake release works properly, you can probably ignore the hissing sound for a long time.
If it does not release, there is a small manual-release lever intended to be operated by poking your foot up under the dash above the parking brake pedal.
In neutral, as in Park, the valve (a small plastic or nylon assembly with two hoses connected to it) remains closed. In one of the "moving" gears, the valve opens, sending vacuum to the canister above the parking brake, which then pulls a lever connected to the parking brake pedal to release it.
It's a fairly simple system that is prone to a few faults:
1. Leaks are possible in the hoses, in the rubber diaphragm inside the canister, or in the valve assembly behind the brake pedal. Such leaks can cause hissing (and the fact that it only occurs in neutral really doesn't eliminate any of these as the problem) and also reduce the vacuum to the canister so that there's not enough strength to pull the lever. You can usually find the leak by crawling under the dash with the engine running and listening (provided you can set the parking brake while the car is in neutral, so you can do this safely... be careful NOT to move the gearshift into D or R while doing this, and I recommend blocking the front and rear wheels first).
2. If the valve, which mounts to the steering column above the brake pedal, is misadjusted (or if the PRND21 indicator needle is inaccurately positioned, you can adjust this back into position with some trial and error. I think the valve body also holds the contact for the backup light switch, so chances are you can get all three features (PRND21 indicator, brake release and backup lamps) to work properly by adjusting the valve position properly. The valve rarely leaks unless it is broken... you can pull off the hoses to see if their fittings on the valve body are cracked or broken off.
3. If the leak is inside the canister, there's little you can do except find a good canister in a junkyard and swap them out. The 1969-73 canisters are interchangeable, I believe, and with some creativity you can modify one from a '67-68 or '74-'78 to work. You can also use one from any '69-73 fullsize Chrysler, Plymouth or Dodge that was equipped with this option (it was standard on Imperial).
4. If the leak is in a vacuum hose, these are easy to replace as vacuum hose is sold by length at any auto parts store. Cut off a quarter inch at the end of one of the hoses and bring it in to match it up.
One final note: your parking brake is also your only emergency brake. It is vital that it be in proper working order, even if the automatic release doesn't work. Many people ignore the brake's very existence, and that causes the pedal assembly, the cable to the rear brakes, and the mechanism inside the brake drums to freeze up or rust. It's worth the effort to make sure the p-brake operates freely and is adjusted so that it can stop the car yet doesn't bind or drag when released.
From James:
I don't know if the system is the same as in '76, but if it's working properly it will hiss when you shift into neutral or park, but only for a few seconds, this is just the mechanism doing its thing so you can apply the parking brake (which can't be done in RD21). If yours keeps hissing, then you have a problem.
From Ross:
That could be the actuator for the automatic parking brake release. I had the same noise on my '78 NYB and it kept getting louder. As it turned out, the actuator went bad and caused a vacuum leak. It's now temporarily disconnected until I find a new unit.
Question from Larry (1982):
When I shift to reverse in my 1982, there is a sound like the drive shaft has a lot of play in it. Is this normal? Or are the U joints the cause of the problem, or something else???
Replies:
From Dick:
This is a very common problem with these cars. The problem is the idle speed is so high that the driveshaft "clangs" into gear, especially reverse. If you are shifting into reverse too soon after you start the car, this makes the problem worse, if it is an EFI car. I think yours is a converted car, so in your case, you can fiddle with the fast idle setting on the choke linkage and perhaps get it to reduce a bit in impact to the driveline.
From Dave:
Ah yes, - the dreaded "reverse sqwauk".
It may help to service the transmission (actually service it and not just change the fluid & filter). By that I mean adjust the bands. When the reverse band gets loose, - the problem gets worse. It could also be the band itself, - there were some problems with "carbon" building up on the reverse drum, and then the band will "shudder" when it tries to grip the drum, - causing the noise. Could be U-joints, - but usually it is not. A lot of "slop" in the differential will aggravate this noise too, - most of the diffs are pretty sloppy, - the side/spider gears are usually a LOT looser than they need to be. There are selective washers available to tighten things up a bit in this area, but it is rather expensive to have done, and I have done this, as well as adjust the bands, make sure the engine idle is not too hig, - creat a big bill, and get very little improvement in the whole situation. I think the true "fix" (according to Chrysler anyway) is to replace the reverse band & drum (the updated band has a different material for the lining). 'Course that will jack the bill up
quite a bit!If it was mine, - I would just make sure that the reverse band isn't about to fall out, - make sure the idle speed is as low as possible, - but most of all I would avoid moving the shifter directly from PARK into reverse. If you always shift to "D", - and *then* shift (quickly) from "D" to "R", - the noise is practically non-existant.
One of the Chrysler reps told me one time to try a bottle of "sure grip differential additive" in the transmission. Supposedly the additive would remove the carbon from the drum, and help the situation out a bit. Seems to me we tried that a few times, - but with mixed results. Might be worth a shot though (if you can't remember to shift from D to R instead of from P to R that is).
From Leo:
I have been driving my '83 now for 14 years and I believe the reverse shift clunk is patented by Chrysler as every other Mopar I owned does the same thing only the '83 has a differnt sound. Sounds like it grinds a little bit before the Clunk. Just enjoy it, you always know when it is in gear!
This page last updated October 4, 2004. Send us your feedback, and come join the Imperial Mailing List - Online Car Club
