93 lesabre Tranny Issue

hey folks, first time post here, my 93 lesabre which has had zero tranny issues since i've had it for 5 years decided to cause trouble today. There has never been any slippage or shifting issues at all with this car at all. This morning however, it shifted properly into reverse, backed out of the garage, then when I shifted it into drive you'd swear you were in neutral, no positive shift felt at all, continuing to move the shift to first, I could get the car to move, although it would slip if you step hard on the gas, getting up to speed and shifting to second(manually), second gear seems to engage properly and no slippage in the transmission at all when you step on it. Also reverse works with no slippage. The same slippage occurs in drive and overdrive. Could this sudden change overnight be something stuck or a module, hopefully someone will have heard of this happening and have a solution, I do have a parts 92 lesabre with a good tranny, but hoping to save me some work with an easier fix. Thanks in advance for any input!!

Your symptoms are similar to mine once..
The pump in the transmission quit in mine..
To check the transmission pump,to see if your pump is working. Disconnect a hose to or from the transmission radiator cooler and see if there is good flow, This could be messy so prepare..

The TCC control line from the PCM to the electronic tranmission, if inoperative or broken can cause these same symptoms.

Good Luck

Your symptoms are similar to mine once..
The pump in the transmission quit in mine..
To check the transmission pump,to see if your pump is working. Disconnect a hose to or from the transmission radiator cooler and see if there is good flow, This could be messy so prepare..

The TCC control line from the PCM to the electronic tranmission, if inoperative or broken can cause these same symptoms.

Good Luck

Thanks for your input bassasasin, I think that sounds like the route i'll try!!

I hate to be the bearer of bad news, however, you probably have just experienced the beginning of a very common problem in an older, or “high mileage” 4T60E transmission. :uhoh: The problem is with the internal lip seal to the input clutch, in the input housing. As they get old, they shrink and get hard, therefore, they do not seal to the housing the way they should. This problem will cause the input clutch pressure to bleed off and not apply the clutches. Once the fluid starts to warm up, the seal expands enough to seal and will usually be fine until the fluid is cold again. You can get an additive at the dealer similar to Lucus or Sea Foam, that will soften the seals and may work for a while, however, this is not a long-term cure!

I have seen a few tricks that worked for awhile, until a rebuild or trade-in can be accomplished.

One trick you can use to overcome the delay is, on cold mornings, (below 30 deg for me) start your car and let it idle for 5-10 minutes to warm the fluid. (It could take longer depending on how cold)! After the warm-up period, shift to reverse or first gear immediately. (I prefer to use reverse, because it will engage with lower line pressure than 1st and when it engages, will not slam into gear as hard). Do not select any other gear! :nono:Let the car sit in reverse, or first gear until the gear engages. (Keep foot on brake while in gear). If you live in a colder climate, where every morning is below 32 deg, you may have to do this every day until the temps start to warm up!

Another suggestion, disconnect the vacuum hose to the modulator and plug it. With the hose removed from the modulator, the line pressures should go to the specified maximums and your Trans should shift into gear, as soon as engaged. Again, this is not a cure for the problem; it is simply another test to verify if you have low line pressure. Remember, the vacuum modulator controls the pressure of the transmission fluid and in conjunction with the accumulator, controls the firmness of the shifts. Try this & post back!

BTW, GM has redesign the internal lip seals and the new design has proven very effective as a long-term solution to the problem. Most all of the rebuild kits available today, have the new design seals.

In conclusion; The internal seal leak will appear without warning and may first appear soon after a fresh fluid/filter change or flush! :screwy:

thanks hotz28, more stuff for me to try, i have to deal with a leaky hot water tank tonight but i'll be at this stuff friday night and post back!!

thanks hotz28, more stuff for me to try, i have to deal with a leaky hot water tank tonight but i'll be at this stuff friday night and post back!!

Back after trying all the stuff, when I took the tranny lines off I had lots of pressure, and when I took the vaccum line off the modulator it was trying to move in drive, so I took the pan off the tranny and found a small piece of metal in the bottom of the pan, later found out that it broke off the forward band on the positioning tab, I visited a tranny shop and the guy showed me where exactly it came from and said with 405000 km on it the barrel was problably going to be worn to the point of self destruction anyway, so I think I'm going to let go of my baby, Thanks for everyones help!