NEED TRANSMISSION HELP BUICK LACROSSE

[Evaddave 87gn]

OK here is the deal, my eldery parents drove 500+ miles to visit. They recently had the transmission rebuilt in thier 2005 Buick Lacrosse CXS. The car drove in with no problems. Today however my wife drove into the city and on the way back the car started to shift like my GN. VERY HARD SHIFTS! Slammed into first and hit hard into second and slight knock into 3rd and fourth. The car continued to due this for the remainder of the trip back from the city. This would happen when she pllued out from any stop. However when I drove the car about thirty mins later the car shifted fine. I shook the front end down and found the axles seem loose with play in the wheel bearings.

I am thinking that there my be dirt in the transmission, but I am not an expert. Looking for some opinions on how to proceede. I am going to try drive the car to the city in the morning to see if I can get it to repeat the symptons.

There is also some vibration in the wheel when I hit the brakes but this is most likely the brakes.

Also if anyone knows the torque spec for the front axles that would help alot.

Any insights would be apperciated.


Dave

 

[Steve V]

4t80E? Northstar engine? Sounds like the line pressure is commanded to the max. Check DTC's go from there,could be 3 separate issues.

 

[Evaddave 87gn]

Update...

Axles are to be torqued at 118 lbs, and they are. I am headed down to trans shop to check the codes.

Yeah Steve I agree 3 separate issues. The car has a 3.6l v6 I am unsure of the transmission. I think it is 4T65E.

I read online about a EPC throwing a code 1811 that can cause this type of problem. I also read about the TPS giving eratic voltage that can also cause this issue. I checked the TPS and rose and fell as it should.

I think I can change the EPC solenoid with the trans still in the car, but not sure....Anyone??....

 

[chopped39]

Its either the solenoid or the valve sticking in the valve body. The side cover has to come off to change it. It can be done in the car. I do them on a lift though. The left side shaft has to come out and the trans has to come down which means the frame has to come down a little. Make sure the eletrical connector is all the way in . Unplug it and inspect terminals

 

[Steve V]

If it is 4 speed it is 4t65e,the are notorious for 1811 max adapt and longshift code. That means trans adapts are pegged and could be a clutch clearence(excess) issue or the PC solnoid itself. If it's a 6 speed...prob not in 2005....that's a different animal alltogther.

 

[Evaddave 87gn]

Update:

Steve and Chopped you are correct....

The trans gave a 1811 code. The shop that did the service advised my local shop to clear code and have the car driven back to IN. They said the transmission went into saftey mode, and feel if it does it again it would still be ok to drive the 500 miles. They said they will take responsibility for any additional damage. So my parents are going to take it home Monday and let the previous shop repair the problem.

I bought some new rotors and will install them in the morning, it needs wheel bearings but dad does not want to change them just yet.

THANKS GUYS!

Dave.

 

[Steve V]

Dave,

Tell them no worries it will make it just fine. It just may shift like it has a shift kit. Common prob with 4t65e. Theres a bunch of info on the net about it. Trans rebuildings is usually not needed,so hope that was not the orignal problem.

Good Luck!