Grand Prix 4T60-E Trans

:banghead: 1993 Grand Prix SE 3.1Liter 4T60-E :banghead:

I have a 93 Grand Prix with a 4T60-E and I just changed the transmission fluid and filter and after doing so I made sure the filter gasket and filter were properly fitted and put the pan back on and topped the fluid off at the proper level. Since doing this the transmission does not want to fully go into gear when the car is cold. But, after it has had a chance to warm up for a few minutes it goes right into gear. When driving the transmission shifts through all the gears smoothly. It does not slam into gear when going to any gear from park or from one gear to another such as drive to reverse and reverse to drive. If I pull the shifter down into 1st when it’s doing this it jumps right into gear. I have a feeling this is not a clutch problem because it operates normally when it’s been running a couple of minutes, possibly a pump problem or a loose line/component where the filter is located?? Maybe I bumped something that could be causing this. Any input on this matter would be great!! :frown:

:banghead: 1993 Grand Prix SE 3.1Liter 4T60-E :banghead:

I have a 93 Grand Prix with a 4T60-E and I just changed the transmission fluid and filter and after doing so I made sure the filter gasket and filter were properly fitted and put the pan back on and topped the fluid off at the proper level. Since doing this the transmission does not want to fully go into gear when the car is cold. But, after it has had a chance to warm up for a few minutes it goes right into gear. When driving the transmission shifts through all the gears smoothly. It does not slam into gear when going to any gear from park or from one gear to another such as drive to reverse and reverse to drive. If I pull the shifter down into 1st when it’s doing this it jumps right into gear. I have a feeling this is not a clutch problem because it operates normally when it’s been running a couple of minutes, possibly a pump problem or a loose line/component where the filter is located?? Maybe I bumped something that could be causing this. Any input on this matter would be great!! :frown:




right next to the filter inside the trans pan theres something called an accumulator. it has 3 trans lines going into it. often times when fighting the trans filter to get it out people bump on of these lines. if their not fully in then youll have propblems with the shifting

drain the trans fluid
drop the pan
make sure all 3 lines are properl seated into the accumulator
and check the oppisite ends of the hoses

The vehicle has no problems with shifting. Just problems with going into drive or reverse when vehicle is cold. Once running a few mins everything works fine.

The vehicle has no problems with shifting. Just problems with going into drive or reverse when vehicle is cold. Once running a few mins everything works fine.


how many miles on the vehicle and how many times has the fluid been changed?

how many miles on the vehicle and how many times has the fluid been changed?
195K, and I'm not sure. I just picked it up as a winter car but planned on keeping it around for awhile. I also don't think that's relevent to the problem. This issue could have been there when I bought the car because when I drove it the vehicle was already warm and there would have been no possbile way to detect it. It's just a $600 car but my girlfriend is the one who drives it and I don't like the idea of it doing this.

I hate to be the bearer of bad news, however, you have a common problem in an older or “high mileage” 4T60E transmission.:crying: The problem is an internal lip seal to the input clutch, in the input housing. As they get old, they shrink and get hard, therefore, they do not seal to the housing the way they should. This problem will cause the input clutch pressure to bleed off and not apply the clutches. Once the fluid starts to warm up, the seal expands enough to seal and will usually be fine until the fluid is cold again. You can get an additive at the dealer similar to Lucus or Sea Foam, that will soften the seals and may work for a while; however, this is not a long-term cure! The only long-term cure, is to remove and replace the seals. The Trans will need to be removed from the car and disassembled. Better to let a pro do this, since special tools and equipment will be needed. In this particular case, a rebuild would not be a worthwhile investment in a $600.00 car! So what do you do :confused: I have seen a few tricks that worked for awhile, until a rebuild or trade-in can be accomplished.

One trick you can use to overcome the delay; On extremely cold mornings, (below 30 deg for me) start your car and let it idle for fifteen minutes to help warm the fluid. (It could take longer depending on how cold)! After the warm-up period, shift to reverse or first gear immediately. (I prefer to use reverse, because it will engage with lower line pressure than 1st and when it engages, will not slam into gear as hard). Do not select any other gear! Let the car sit in reverse or first gear until the gear engages. (Keep foot on brake while in gear). If you live in a colder climate, where every morning is below 32 deg, you may have to do this every day until the temps start to warm up!

Another suggestion, disconnect the vacuum hose to the modulator and plug it. With the hose removed from the modulator, the line pressures should go to the specified maximums and your Trans should shift into gear, as soon as engaged. Again, this is not a cure for the problem; it is simply another test to verify if you have low line pressure. Remember, the vacuum modulator controls the pressure of the transmission fluid and in conjunction with the accumulator, controls the firmness of the shifts. Try this & post back!

BTW, GM has redesign the internal lip seals and the new design has proven very effective as a long term fix for the problem. I believe about all the rebuild kits available today, have the new design seals.

In conclusion; The internal seal leak will appear without warning and may first appear soon after a fresh fluid/filter change or flush! :screwy:

Did this car have any type of warranty when purchased?

Nope, no warranty. It had 195,000 miles when I bought it and its a 93, What kind of warranty could you really expect for a $600 dollar car? I'll have to disconnect the vac line when the car is cold and see how that works. But I'm still not certain this is the problem either because if I leave the car into drive or reverse it does go into gear approx 50% of the way, then 30 seconds later you can feel it engage even more. I'm going to get some Sea Foam, but I can leave that in right? I won't have to change the fluid again??

Nope, no warranty. It had 195,000 miles when I bought it and its a 93, What kind of warranty could you really expect for a $600 dollar car? I'll have to disconnect the vac line when the car is cold and see how that works. But I'm still not certain this is the problem either because if I leave the car into drive or reverse it does go into gear approx 50% of the way, then 30 seconds later you can feel it engage even more. I'm going to get some Sea Foam, but I can leave that in right? I won't have to change the fluid again??
Yes, just add the Sea Foam and leave it in and you do not need to change the fluid. It might help for a while, then again, it might not! When a dealer has a car on the lot with this problem, (when cold) they usually have the car "warmed up" for you before a test drive! This is an attempt to hide the Trans problem, not as a courtesy to the customer to have the interior nice & warm. Was this particular car nice & warm for you when you took it for a test drive?:crying:

If you can get the transmission pressure tested while cold, you would probably see line pressure below spec. until it warms up. Specification at idle are, 74-85 in D4, D3, D2, 79-95 in P,R,N, and 158-170 in L.

I totaly agree with hotz28 sounds like the seal is bad or the piston has groved out.

Well isn't that just a fart in the bottle. How much does that cost to repair? Almost as much as a rebuild??

In my area, an R&R on the 4T60E runs about 600 bucks and a rebuild kit installed with all new clutches, seals & miscellaneous parts, would run another 600-800 bucks. Total job, average (in this area) = $1200 to $1600. I am sure that would probably double in some areas like, for example New York, due to inflated labor cost, price gouging and protection payoffs to the street thugs.:smokin:

BTW, it would not make good sense to only replace the seals on a high mileage Trans! The labor cost would be almost as much, as a total rebuild. (The complete rebuild kit, cost only about 150 bucks, the rest is labor)!:sunglasse

Did you find a solution to your problem?

Yes I did, I added some Lucas Transmission Additive and it fixed the problem. I should have just left the old fluid in there. I was told that when I changed the fluid the old type was thick from being dirty and the pump picked it up easily and was allowing for my pressure through the trans but when I changed the fluid its new and its thinner and the pump has a problem keeping its prime plus the fluid does not have as much pressure.