Park Avenue 1999 transmission bucking.

[rali5255]

Recently noticed a bucking problem when gears change and its seems like there is a hesitation to change speeds.

I took the car to transmission for diagnostic test and the garage wants rebuild the tranny.

All gears do go in and vehicle has no other noise.

The last oil change was about 80,00 km

Since this problem is evident in 1-2, 2-3 gear changes can it be a common problem?

Any advise is welcome as I try to avoid a complete tranny job.

[maxwedge]

There is no way to diagnose this from here, this could be an issue with a failed solenoid, an engine misfire, a full scan that read trans functions would eliminate or point to possible issues other than an overhaul, try another shop.

[rali5255]

Thanks,

The engine tune up was done 80,000 miles ago. Will get a second opinion but prefer checking simple things first.

[BNaylor]

I'm confused. In one post you mention kms and in another miles. What is the current mileage? Also, how is moderate takeoff/acceleration? Any launch shudder?

I agree with maxwedge - Shep. Get it scanned and see if a P1811 DTC is stored (max adapt, long shift). This DTC does not trigger the SES/CEL light but stores for retrieval. Common problem with GM cars equipped with a 4T65E autotransaxle.

[rali5255]

Thanks guys for the response.

The correct mileage is now 230,00 KM. The last transmission oil change was at 130,00 KM. Sorry for mentioning MILES what I meant approx. in miles.

During takeoff/acceleration moderately, its seems slow to respond. As it ramps up you get that kick briefly then gear changes. This happens mostly when the car warms up.

Lunch shudder, yes.

[BNaylor]

Thanks. So approximately 143,000 miles. So would you describe the kick as a hard or harsh shift?

[rali5255]

I would say harsh shift.

[BNaylor]

Without rewriting the book on this type issue we have a well discussed thread over at the LeSabre forum that may be of interest to you. See link below.

Click here

[heyyo302]

Hello try this:-
Transmission fluid is clean
While lugging is occurring, I hit the brake pedal lightly; the "lugging" or "bucking" immediately stopped then Immediately returned when I released the brake, so I suspected my "Lock up" condition is less than perfect.
Here is the part that keeps me up nights! During this "lugging" at the 45 to 60 mph acceleration, my buddies on board computer reports the TCC signal is in fact active.

[rali5255]

Its been a log time but know have some feedback for our PA forum.
I tried the Sea foam method a few months ago. Soon after the addition of the cleaner I did a tranny flush. Not sure what it means but according to the mechanic, he connect the hoses to an external setup and filtered the whole system.

The Car was still giving that same kick as it did before. I added a tranny treatment after and still problems.

I was now ready for a drop down oil/filter change after all attempts BUT know the car begins to work o.k. with no additional work done to it.

During pickup the gears go in normal without any kick. Its know 7 days and no problem.

Cannot explain, but I will still continue with the oil/filter change. The only explaination I have is its now beginning to get cold in Canada. Temperature in the oil/motor-sensors????

Anyone has any other suggestions?

[rali5255]

Well got good news since my last update.

After using the tranny cleaner and having the garage do the flush with no good results. I did what should be done after using the cleaner, change the oil and filter.(My mistake)

I replaced the filter and used the correct oil and now the car drives as it should. No more slipping/bucking during gear changes.

Excellent news, but most all THANKS to the forum for the good advise.

Thanks again......