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Pontiac Repair/Transmission Service


My 4T65E transmission (2002 Grand Prix 3.8 NA) is periodically (once every 2 months) setting a P1811 code.
It runs and shifts fine otherwise.  Fluid looks great.
I'm going to attempt to replace the valve body with a rebuilt unit from GM.  

How is the side cover accessed?  Do I remove the 2 rear engine cradle to body mounts and lower the cradle with 2 floor jacks?  Also, how do I remove the left half-shaft?  Can I pry it out with a bar or do I need a puller or slide hammer? Does the right side need to be removed, or is there enough slide to accommodate the 2 or 3 inches I need to lower the trans to remove the cover.

Any other recommendations or comments would be most welcome.


ANSWER: Hi Colin:

Chances are if the fluid looks good and your NOT having a hard/harsh shift you will not need a valve body. It just needs a pressure control solenoid. Only use a GM solenoid and replace the gasket on the side cover even know it's reusable replace it. You can get it out you will need a couple of jack stands under the body to hold the car up and then a couple more to support the engine sub frame on the left side of the car and a jack. once the car is up on jack stand good and high you will need to lower the left side of the engine support (sub frame) un bolt the left transmission mount from the frame. lower the left side of the frame. disconnect the intermediate steering shaft from the steering gear. remove the lower control arm from the steering knuckle remove the left outter tie rod from the steering knuckle. once it all lowered down and far as it will drop use a jack inder the transmission pan with a 2X4 on it to distribute the lifting force across the pan (as not to crush the pan) and then jack up the engine off the sub frame and you will then be able to remove the side cover. You will also need to get the axle shaft out of the transmission before you take the cover off. Like I stated in the beginning if you cough this early enough you will not need a valve body and it's a huge savings.  Good luck :-)

---------- FOLLOW-UP ----------

QUESTION: Now I'm confused.  On my car, the side pan needs only 2 inches to clear.
I did not see any need to remove the trans mount. Did I miss something?
I understand about the steering shaft, but the tie rod shouldn't have to be removed from the knuckle.  It should just pull the knuckle in a little once the half-shaft is pushed through the bearing and the sub-frame is lowered.  On my car, I can remove the shaft without separating the ball joint.

Also, are you suggesting I lower only the left side of the sub=frame?

Also, how do I remove the shaft from the trans?  Can I pry it out and push it back in???

Yes you can use a pry bar to remove the axle shaft. and yes only lower the left side of the sub frame. when you have that lowered and the suspension unhooked from the sub frame you will jack the engine up and then to remove the side cover you will push it up tip it out on the bottom and then slide the whole thing out the bottom of the car there is no room to get it out from the top. Trust me I do these a lot that is the only "easy way to do this "

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Todd Puccio


General auto repair,electrical issues,driveability issues,anti-lock brakes,SIR systems,HVAC,engine performance,Gm specific. I have worked at my current dealership since the 1990 model year anything much older than that I have limited exposure to. I do not have very much transmission experience so those question you may want to ask of another expert. When you send me a question let me know the exact make/model/engine and year for the car or suv you have it makes it easier to answer the questions that way. If your happy with the answer I gave you please feel free to Donate. This is a free service to you and I am not compensated at all by this web site. I have 22 years of experience to share with you and my knowledge wasn't free to me. I had to pay for my education.


Experience in the area: I have been a technician in GM dealerships for over 22 years and I am a ASE master technician. I work at a Buick and GMC truck store Previously I worked at a Pontiac GMC store for 18 years. I Served a a lead technician when dealership was on a team system. I just recently moved to a Buick,Hummer,Saab Store when my franchise was purchased by this dealership. Organizations: ASE master technician


Education/Credentials:High school diploma,2 year vocational school degree 2 year college degree. Associates degree in applied sciences (auto technology)Awards and Honors: GMC master technician

Awards and Honors
Master GMC truck technician Master ASE technician in 9 categories

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