Transmission bucks when underload at low rpm's. does not do it when transmission is cold takes 10-15 mins till problem shows up. already changed trans fluid and filter. Is there a way to do a power flush with out going to a shop. I feel that there may be some remianing old fluid in the torque converter when I changed it. The old fluid had about 80k on it.
"Transmission bucks" is anything but descriptive... Transmissions usually slip or shift rough, I've never heard a trans described before as "bucking". Why do you think this is a transmission problem? Sounds to me like an engine problem.
By the way, at 80K, the transaxle was more than due for a change of fluid and filter so this is good that you took that action. Draining the fluid gets about 50% and you are correct that the remainder is concentrated in the torque converter, as well as the solenoid valve body, cooling lines, etc. You can get another 50% of the 50% that remains by draining it and removing the filter and draining that too before refilling again. This would leave about 25% of the old fluid.
Bob
Per your advice decide to check engine 1st. Found small black hose about 4 inches long that was connected between value cover and intake air sytem that when engine was acelerated hose would parially colapse and make whistling sound fix it and problem has gone away.
Still have a another problem remaining some times when putting car in reverse transmission hesates then with a loud band enages. If I let it sit in neutral for just a few seconds then put in reverse it works fine. Am I wasting time draining the fuild a second time from tranmission to get as much as remaining old trans fuild or could this be a problem caused by something else like electronics.
Glad you found the engine problem.
On the transmission, your vehicle has the infamous "reverse slam" characteristics. Go to the Saturn Forum and follow the Wolfman's fix. Many have said that this has saved them hundreds of dollars and worked for them. It is basically just running the car at idle in reverse with clean fluid and new filter and a trans additive for 30 minutes, then draining the fluid and refilling again. This cleans out the valve body which clogs if you do not drain and change the fluid often enough.
Bob
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