Slippery when wet (transmission slips during rain)

cadillac

#1

I have a 2001 Cadillac DTS 91K miles I notice that when i drive it in the rain or any wet surface of a good amount for more than 20 min. the transmission will slip, the tack stays at 22 hundred or so then jerk and then be ok that will do it for every gear, does not do it down shifting and when it dries off its completly fine! My mother had the same issue with her 03 Bonneville SE and she ended up having to replace heres maybe a month ago, Is this common for GM trannies, a kind of warning?PLEASE HELP


#2

It sounds to me like you might just be talking about hard shifting rather than slipping. For slipping the engine can rev way up without any power making it to the wheels, and the shifts would be incredibly soft (sort of what slipping is). Your description is not all that clean though, so its hard to say.

But if you are absolutely certain that this is only a wet weather issue - and only a wet weather issue - then the transmission actually slipping doesn’t make much sense. Hard shifting does.

Wet weather problems are almost always about electrical components getting wet. Your transmission is computer controlled & has a bunch of electrical connectors on it that communicate back & forth with the computer. The computer has various “safety” mechanisms that will kick in if it detects a problem. So, if one of your electrical connectors was cracked or something, or you had a degraded wire or whatever, it could easily malfunction when wet. The computer would notice the breakdown in communication & turn on some kind of “safe mode.” There are various modes, but one would involve hard shifting (the jerking).

Whatever you do, don’t take it to the shop your mom went to (was it AAMCO?) If it was exactly the same issue then a transmission replacement probably wasn’t needed.

If you have a regular local mechanic (regular, down-home shop - not a chain “auto care” place) just tell then about it. They can easily put it on a lift and inspect your splash shields and transmission connections, clean them up, whatever.

If they get confused, or if you don’t have a regular local mechanic, start asking around for the best transmission shop in town - but not one that is a national chain (e.g. AAMCO). Bring it to that shop, give them the symptoms and let them check it out.

If you end up at a transmission shop they should put the thing on a scanner to read what’s going on with the tran operation. If they do that, you can ask for all of the techie info they have (especially any error codes) and post it here for comment.

Are you absolutely certain about the wet weather connection?

Is your check engine light on?


#3

Most definatly, I think its some kind of electrical issue because it ONLY does it in the rain never ever any other time. Its as smooth as you’d expect from a Cadillac as soon as its dry. What youve said about a splash guard possible being damaged makes sense as one time the speedometer stoped working for like 4 or 5 minutes after i had gone through a larger puddle, it came back but I think some control module or group of wiring is getting wet when it shouldnt be, I do have a trusted mechanic for my other cars but I’d normally take it to the dealer as its mostly a “garage queen” but ive had to drive it latley more than I want, but it does not leak any fluids and I insist it ONLY has this issue in rain.
I will take it to my local guy to see what he says!