Transman, need expert advice

I’m having a problem finding the location of a pressure control solenoid in a 1999 Chev Venture tranny.

I used to have a print out of a worn one that was replaced, but of course when I need it I don’t have it.

It’s the old question of the ‘harsh shift’.

Thanks for your time.


I’m not Transman or an expert but I’m pretty sure it is under the side cover of the trans - which involves fairly major surgery (lowering of subframe & trans via driver’s side to access the side cover).

Yes, that’s it.

Thanks cigroller.

I just wonder if I have this diagnosed correctly?

Final post on this subject: another poster had the system of access posted before I got back there. All is good.

I had suggested he try a fluid and filter change first so hopefully he won’t have to go through all that.

Sorry Roadrunner getting back to you so late. The PCS on a 4T65E is under the side cover. Pull the cover, the valve body will be right there in front of you, look in the 9 O’clock position, the PCS is there installed into the side of the valve body.
Were you able to scan it to see if it is in limp mode?? The PCS’s on the 65E’s were very troublesome and we have replaced many of them. I usually check them with my scanner. I can monitor them and even change the current on them while checking them with a scanner and pressure guage. I ask because I would hate to see you go through the pain of taking that side cover off when the PCS is ok.

Anyway, here are 2 pics of the PCS in your trans. Your trans is going to have one or the other. Its the same PCS, they look slightly different but they are interchangeable.



I appreciate your (as well as others) taking the time to reply.

I don’t think the fellow I’m trying to help (on another forum) has had a scan done but will ask.

Since the subject has come up - I’m driving an '00 Silhouette with the 4T65E. Every once in a while I start it up and it seems to be in some kind of a bump shift mode (I think there is an actual name for such a thing?). It basically jerks hard into each gear. I recall reading something here and there about certain conditions leading to the trans computer being out of the loop and control going to straight line pressure or something like that. But I’ve also come across info on the chronic PCS issues in these things.

The thing about my problem is that it is very infrequent (it happens like 1 time in a 100) and literally behaves on a toggle switch logic when you start the van. I can turn it off and back on and it is back to perfectly smooth operation. Its either just bump shifting when you start it and keeps doing it for as long as you drive. Or (usually) it shifts normally and stays that way - i.e. it never starts up as the trans heats up or something.

Does that sound familiar? And is there some list of possibilities/probabilities?


When I still had my 2000 Silo the harsh shift started around 70Kmlies very seldom on warm up but after warm it would act up.

Pull off, shut down, go have a coffee or shop and come back. Start up and the same thing repeated itself.

I talked to my local tranny guy and after looking at it AND scanned while mobile, said we COULD try a fluid and filter change as there may just be dirt in the valve.

He did the change, took a road test with me and it seemed to be fine even after it warmed up.

For a month after it ran like new then one day it started over again.

One last fluid and filter change (NO flushes) and that was the end of the problem.

I guess I got off lucky. My daughter has it now for over a year and has had no problem.

After a close inspection of the drained fluid we saw dirt in it. Too long between changes.

My tranny tech said if that last change hadn’t done the job he would have replaced the PCS.