95 buick riviera overdive problems

riviera
buick
transmissions

#1

My car has been have overdrive problems for a long time while driving on the highway it will stay in overdrive as long as i keep my foot on gas pedal or brake or in cruise control as soon as i get on the highway. As soon as i go off cruise so does the overdrive and will not go back in till i shut the car off and start it right back up. It makes for a long trip. I had trany oil changed does not effect it at all thank you


#2

You’ll need to improve your description of what is happening, including using a term other than “overdrive.” Lots of people use that word to mean different things.

It sounds to me like you might be saying that the transmission is going into limp mode (probably 2nd gear only). But I can’t even tell what conditions make it happen or even what exactly is happening.

"on the highway it will stay in overdrive as long as i keep my foot on gas pedal or brake or in cruise control"
How or why are you keeping your foot on the brake while on the highway? What is it that triggers whatever is happening? Is it just kicking the cruise control off that does it? What - exactly - happens next?

Is the check engine light on and has the car been scanner for error codes?

Of course, I’m not sure that it matters whether you can clarify or not since your best bet will be a trip to your best local transmission shop.


#3

it will stay at 2000 rpm if i hit cruise control right away on the highway going 60 if i go off cruse control and hit brakes till i am going under 45 mph then i could go back to overdrive but if i let it coast just a little bit then the rpms will get up 2500 to 2800 at 60 mph and will not go back into overdrive till i stop and turn the car off


#4

the check engine light is not and i have not got the car scanned myine has an od 1.5 so the local auto parts store cannot scan it


#5

That didn’t really help clarify anything. For one thing you’re still using that word overdrive and your description is not much clearer. When you say overdrive are you just talking about 4th gear? 4th gear will be overdrive, but then some people will mean 4th gear with a torque converter locked up when they talk about overdrive. Yet others call it “overdrive” if the transmission downshifts during acceleration. In basic terms overdrive is just anything under a 1:1 gear ratio where the drive shafts turn faster than the engine. I don’t know the ratios on a '95 4t60e but 3rd gear is probably Drive and 4th will be overdrive.

But people use it in all sorts of different ways so you using it doesn’t help.

It sounds to me like you’re saying that once it downshifts (when/after you slow down) it won’t up shift again back to 4th. So you’re either stuck in 3rd for some reason or it is going into limp mode.

Anyway, the story still doesn’t change. Someone who really knows transmission is going to need to drive this car and put it on a scanner.


#6

You’re going to need to have a trans shop scan it since it is not OBD II. They have the proper scan tool for the job. Its sounding like you are describing a TCC lockup problem.

transman