I had a trans temperature gauge in my hotrod Buick and one day when I noticed it starting to slip the temp would go from the normal 150-160 up to 250+. Managed to nursemaid it home keeping the temp down and sent it off for a performance rebuild out of state. The rebuilder said I lucked out as with many of those he gets in have to have new hard parts due to heat damage. As for the fluid, if the color is brown is also probably smells burnt. Time for a rebuild but first drop the pan, check the filter to see if it's clogged. My car had a lockup converter which I usually locked up when racing. That cuts down the slippage which = more HP to the rear wheels but is not good for the converters lockup clutches. Once while driving in town the car was hesitant to shift so I dropped the pan and discovered that lockup clutch material had clogged the filter. (time for a new converter) Be careful of the o-ring when you remove the filter. It will sometimes come off the tube and stay inside the trans. Then when you install the new filter with o-ring, the filter won't seat properly b/c of that extra o-ring in there.
Brown fluid indicates either dirty or burnt or both. If the tranny has that many miles and the fluid has never been changed, you do not want to flush it, that will dislodge any contaminates and it will kill your tranny for sure. The best thing to do is drain the fluid, r&r your filter and put fresh fluid in it. If there is a drain plug on the transmission pan, I would suggest drain the fluid in the pan and replacing it with each oil change. Usually the pan only holds about three quarts, so it's inexpensive insurance to keep at least refreshing the fluid three quarts at a time.
You can drain all the fluid by disconnecting the line going to the tranny cooler and running that line into a bucket & starting the motor. If the motor & tranny are cold you won't damage the tranny by doing this. I have friends that have been using that method for years with no problems.
Do they pull new fluid in from another container to replace what is being removed? You wouldn't wan to run the pump dry of fluid.
No. As soon as the fluid flow begins to diminish you kill the motor. Probably less than a quart remaining on an 11 qt capacity transmission.
Thanks for all of the input guys. I am going to drop the pan today and replace the filter and fill her back up. I don't plan on doing the flush as I don't know the history and have heard horror stories of it killing transmissions. If that doesn't help, I'll check with the places that were mentioned. Mainly want to find a reliable place to take it instead of somewhere that will just automatically say it needs to be replaced. Even though thats what I think will probably need to be done.
