hard shift into reverse when cold

[jborning]

I have a 98 Riv the really slams into reverse when the engine is cold. It does not do this when shifiting into drive or when the engine is warm. The rpms do not seem to be that high went it shifts, but it really bangs. I'm afraid of damaging the tranny, but the only way to get out of the garage is to use reverse unless I back in. Any ideas?

Thanks

[cbass45]

I have the same issue with my 98. If I shift in R the whole car moves with it. If I let it warm up for 15 to 20 min it doesnt do it. If any one has a answer please help.

[sprucegoose]

Originally Posted by jborning

I have a 98 Riv the really slams into reverse when the engine is cold. It does not do this when shifiting into drive or when the engine is warm. The rpms do not seem to be that high went it shifts, but it really bangs. I'm afraid of damaging the tranny, but the only way to get out of the garage is to use reverse unless I back in. Any ideas?

Thanks

Wow, this is more common than I thought! I have the same problem with my 98 also, and it only does it when it is cold.

If I don't have time to let it warm up all the way, I start it in Neutral, with my foot on the brake. Then I let it coast down the driveway. Fortunately I have a driveway with a good slope. It sometimes it takes a little nudge with my foot out the door to get it rolling. My neighbors probably think I'm nuts, but I don't want to damage the trans either!

I've been meaning to talk to a dealer about it... If I learn anything I'll post it here.

[cbass45]

I agree on wrecking the trans. I just got the car two weeks ago. It runs great besides this. Since I am in WI, I let my cars run for 30 min before I go to work. Does this happen in the summer at all? I wouldnt think so, but I just want to be ready. I did check with the dealer and he said as long as the fluid was changed every 50,000 miles, dont ever get it serviced untill it breaks. Big bucks to rebuild. He also said that it is also not the first one he has seen do this about 20 or 30 others 97 - 99.


If you get any other info please let us know.

[sprucegoose]

I did a little test on this yesterday... I started my car in P, and then shifted right to D. Like we have said, there is no SLAM there! I left it there for a few seconds, then shifted to N. Back into D again for a few more seconds. After doing this a few times, I shifted into Reverse... No SLAM! At least on mine, this seems to do something to soften it up a bit. Maybe just getting the fluid travelling thru the trans valves etc. for a little bit loosens things up? It sure beats having wait for the car to warm up before you back out of a spot!

It wasn't quite as cold here lately, but still well into the range that usually will cause this, so I think I may have hit on a work-around for the time being.

[HotZ28]

You have what is called "morning sickness". It has to do with the lip seal to the input clutch in the input housing. As the seals get old, they get "hard" and don't seal to the housing like they should. This, in turn, causes input clutch pressure to bleed off and not apply the clutches. Once the fluid starts to warm up, the seal gets "soft" and starts to seal and will usually be fine until the fluid is cold again.

The only thing you can do to correct this problem, is to remove and replace the seals. The Trans will have to be removed and disassembled. Better let a pro do this, since special tools and equipment are needed.

“Sprucegoose” found a trick that I normally mention to help overcome this delay. The reverse and low clutch assembly work together and if your delay is in reverse, start the car in park and immediately shift to low gear or 1st until the car moves, then back to reverse. The opposite applies if the delay is in drive, (usually happens more often than reverse). Start the car, then shift to reverse first, wait a few seconds then shift to drive and you are own your way. This is not a long term cure; however, it will keep you going for awhile until the weather gets above 50 deg. By the way, 50 deg. + or - 5, seems to be the ambient temperature that this condition will appear or disappear!!

[sprucegoose]

Originally Posted by HotZ28

You have what is called "morning sickness"......................................... ........... By the way, 50 deg. + or - 5, seems to be the ambient temperature that this condition will appear or disappear!!

Thanks HotZ28. We appreciate the info and your level of experience here!!

[cbass45]

I found a fix for this from the GM dealer as well.
They have a Seal additive that softens the seals. It was about $55.00 for the treatment. After it was done, it never did it again.

[sprucegoose]

Originally Posted by cbass45

I found a fix for this from the GM dealer as well.
They have a Seal additive that softens the seals. It was about $55.00 for the treatment. After it was done, it never did it again.

Interesting! Is this a GM goodwrench additive, or an aftermarket product they sold you? I was considering a trans treatment as a possible solution (such as Lucas), but dealers usually don't recommend that.

[cbass45]

I dont know if it is by GM...But I was to two different dealerships and they both suggested it. What ever it was it cured the issue. Better than spending 850.00 on a trannie rebuild.

[Sully98]

The same thing happens to me in my 98 i have to let it warm up in the mourning, although iv heard that when it slams hard it was better for the tranny because it causes less fiction, although it does slame very hard.