2003 Buick LeSabre Custom...60K Miles...I know, very low. Transmission APPEARS to slip, but seems to be only after a fairly sharp turn, such as a u-turn. Tranny has no leakage HOWEVER, it does have too much fluid in it. After a 15 min idle, switching through all gears and then a ten minute rest the fluid is 1/4" above the maximum mark. The tranny appears to act fine during normal driving, however with traction control off, from a dead stop I make a right turn and accelerate hard to get into traffic....the tranny does not engage and appears to "slip". Hard acceleration from a dead stop forward with traction control off provides a "burn out", in other words no slippage. Is there some sort of a sway or tilt sensor that disengages the tranny? Has anyone else experienced this? Thanks in advance!

Have you had the car scanned for codes? many trans codes wont trip a light. Does it do this when turning either way, or just one way? Has the filter ever been changed?

You likely have a little too much in the trans. On a right turn the fluid would all go to the driverside and potentially cause an issue where air is introduced and it foams.

That'* my thought as well Bill.

Answers: Not looked at codes...Autozone here I come/Hold wheel full right or full left, traction control off, accelerateate, engine revs then hard clunk sound as tranny engages. Cannot duplicate any other time./Maintenance to transmission is unknown, however it does have too much tranny fluid. Know of an easy way to drain excess not taking off the pan? Just to verify if excess tranny fluid is the culprit.

You can stick a tube down the dip stick tube and suck it out. If that changes nothing then I suggest dropping the pan and changing the fluid and filter. That will also give you a chance to see if there'* anything in the pan that shouldn't be.

Seems the easiest and logical approach. Will be findinding tube to fit down and extract fluid. I beleive the fluid may have been put in and measured on the dipstick cold by the previous person that filled the tranny with fluid. Once at the proper level I will test and post results. Trannies are not my forte. Thank you all for input. I just can not beleive a tranny with 60K on it would be defective.

Extra fluid will NOT cause your problem. We sometimes slightly overfill transmissions to try to correct symptoms like yours. I would drop the pan and check the condition of the filter and filter seal.

You problem actually sounds like the trans does not have enough fluid in it. Before you drop the pan, add another quart just to see if it corrects the condition. I have seen incorrect dipsticks before.

We have done many transmission rebuilds with far lass than 60000 miles.

BTW, can you get this to happen in Reverse??

Hmmmmm....a difference of opinion. I tend to lean towards too much fluid NOT causing problem because in the "older days" too little fluid caused slippage while too much fluid caused leakage but appeared to solve slippage. Fluid expands when hot causing seals, etc. to leak. I have no leakage.

My troubleshooting approach will be thus far....1. Check for proper dipstick. 2. If correct dipstick, then remove excess fluid and test cold and hot including reverse. 3. That failing, then remove pan and filter and inspect. If all appears satisfactory then 4. Replace filter and gasket, refill proper amount and test.

At some point I guess I should make the problem appear and go directly to check codes...a screwed up sensor, or something like that....?

I am curious to know if these transmission flushes are a "good thing" or a "bad thing"....such as Firestone provides. That fix would insure system is clean including the torque converter and refilled with the proper amount of fluid. Problem I can see with that is the filter....change before flush or after or both?...!

I know that on occasion if I shift to reverse from dead stop and immediately accelerate the tranny will not shift to reverse until engine reaches "x" RPM and then "CLUNK", into reverse. Very intermittent. IF I do the same thing but DO NOT accelerate quickly but rather lazily put car in reverse then lazily accelerate. The car is properly in gear and no slippage. Seems to be that if I accelerate SLOWLY then problem never occurs BUT if I accelerate QUICKLY (as in punching the gas) then the tranny slips before engaging.

What is the results of someone possibly mixing two different types of fluid? That thought has come to mind since I am not the only owner.

Flushes are a good think to do to a good transmission and MAY finish off a transmission that has a problem. But before we do a flush, we drop the pan to see if the trans is healthy enough for a flush.

Mixing a small amount of different types of fluid will not do anything to harm anything. But I would add a quart to see if it solves your problem. If it doesn't, you may need internal repairs.

BTW, I have been in the trans business since 1975 and have owned a trans shop since 1984.