Chevrolet Repair: hot transmission, transmission side, transmission fluid

Question
QUESTION: My 2000 Lumina transmission runs smooth until it gets hot.  After driving it for about 45 minutes it starts to bump a little after taking off from a light or any other stopped  place.  What can I do to fix it or not fix it?  The car in not worth but about $1000.
Thank you.

ANSWER: HI LESLIE,,WELL THIS IS A HARD QUESTION TO ANSWER. IS THE CK ENG LIGHT ON ??? IF IT IS HAVE IT SCANNED TO SEE IF THERE IS ANY TRANSMISSION CODES IN THE SYSTEM. IF SO, THIS WILL GIVE THE MECHANIC A IDEA AS TO WHAT IS GOING ON WITH THE TRANSMISSION [[IF THERE ARE ANY TRANSMISSION CODES IN THE SYSTEM...]]HAVE YOU CHECKED THE FLUID WHILE THE CAR IS RUNNING ?? MAKE SURE IT IS FULL..ALSO IS IT CLEAN [RED] OR DIRTY BROWN AND SMELLS BURNED..IF DIRTY AND SMELLS, YOU MAY WANT TO TRY AND HAVE IT FLUSHED WITH NEW FILTER AND OIL..THERE IS NO SURE FIRE WAY THAT THIS WILL SOLVE YOUR PROBLEM..IT SOUNDS TO ME AS IF THE OIL GETS THINNED OUT FROM THE HEAT AND BY-PASSES THE SEALS IN THE CLUTCH DRUMS TO ALLOW FULL CLUTCH PRESSURE IN WHICH WILL CAUSE A SLIP OR AS YOU SAY [BUMP] UNTILL IT LOCKS UP..HOPE THIS YOU AND GOOD LUCK TO YOU,,,TOM..

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

QUESTION: Hi Tom
No the engine light is not on and I have had the transmission fluid changed.   Should it have a different grade of fluid?  Should I have the seals changed?   Thank you
Leslie Ruth

Answer
HI LESLIE,NO THERE IS NO OTHER GRADE OF FLUID TO REPLACE IT WITH.HAVE YOU CHECKED IT WHILE THE ENG IS RUNNING TO MAKE SURE IT IS FULL ??? THE SEALS THAT I AM TALKING ABOUT ARE INTERNAL. THE TRANS WOULD NEED TO BE REMOVED AND TAKEN APART TO GET AT THEM. YOU COULD STILL GET THIS SCANNED AND SEE IF THERE ARE ANY CODES ON THE TRANSMISSION SIDE OF THE PCM TO BE SURE.. SOMETIMES THEY WILL NOT SET A CK ENG LIGHT..IT IS WORTH A TRY..SOME PARTS STORES WILL SCAN THIS FOR FREE FOR YOU...OTHER THEN THAT,,THERE IS NOT MUCH YOU CAN DO..YOU HAVE DONE ALL YOU CAN DO.YOU COULD PUT SOME TRANSMISSION CONDITIONER IN IT,IF YOU WANT TO. BUT THIS SOMETIMES IS LIKE SNAKE OIL !!! JUST WAIT AND SEE WHAT HAPPENS..GOOD LUCK TO YOU,,TOM....