PontiacBonnevilleClub.com

Can't really take it much longer. I've coaxed the tranny into ok performance for a year with TransTune, other addidives, fluid flush, etc. and the problem of the pressure control solenoid has finally gotten to me. It will do a hard shift between 1st and 2nd, after hill climbs, highway driving, etc. When it's cold it works fine, and if I turn off the car and let it sit for a minute it will work fine afterwards if it's been acting up. But overall the car is getting more undrivable.

What will the cost be to replace it? I saw on rock auto parts the part appears to be about only $40. What will the labor be at a transmission shop getting it in and out? I do all my own work on everything, but transmissions I'd rather just have done by someone else.

I got mine done for around $350, but most places will probably be close to the $400-$500 mark.

isnt the pressure solenoid on the external of the transaxle,i thought it was near the v.s.s sensor

Its inside the transmission, you are looking at 8 hours of shop labor, most shop are around $70-100/hr, so at least $500 in labor.

harofreak, of those three sensors in your pictures, which one is the PCS? What are the other two?

Top one is the Shift solenoid
Middle is the Pressure Control Solenoid
Bottom is Torque Convertor Clutch Solenoid

torero500,

You say you DIY auto maintenance...if you have the capability to lift (or drop) the trans, then replacing the PCS really is not that big a deal and you'll save major $$$.

Some tips, whichever way you go:

1) Trans guys I've talked to say that the Borg Warner brand PCS solenoid is less prone to failure than the OEM Delco PCS.
2) You are pre-2003; get a new 2003+ hardened 4th clutch hub installed while you're in there, to extend the life of overdrive.
3) Check drive chain stretch; if it needs replacing, 2005+ 4T65E chains (since the advent of the GXP) are a hardened part less prone to stretch/break.

I did talk to a transmission shop guy today, and he thought replacing the PCS wouldn't do much good. He says his shop has replaced lots of them through the years on all types of cars, and it never fixes the problem much. Now, he wasn't specifically talking about the Bonnevilles. I still think that perhaps our PCS are more prone to failure than other cars, and/or causes more severe problems with shifting than with problems in PCS sensors in other cars.

This is a rough translation, and it sounded better from his mouth, but basically he said it's quite possible that something he mentioned in the tranny is cracked, which allows side leaks that lowers the pressure causing the tranny computer to overcorrect for protection. Basically, it calls for a rebuild.

What's anyone's opinion on his opinion? Are our cars so susceptible to this specific problem that replacing the PCS would in fact go a long way toward fixing the forced computer shifts, despite this transmission shop's opinion? It is a reputable locally owned tranny shop that has been there for years.

GM issued a technical service bulletin regarding harsh shifts cause by the PCS, so it is quite possible that it would fix your problem. That's not to say that there isn't some other problem causing it, too. Some have solved the problem by installing a shift kit.