trans fluid

[ltc86]

Someone has told me that changing and flushing transmission fluid in an aoutomatic is actually bad for the trans and could cause slipping. His explanation was that the auto trans is very complex and the fluid settles in certain parts and flushing it out will cause the parts to work incorrectly. Has anyone heard this and is it true? I mostly hear it is recomended to have it changed. The main reason I am asking is because in my 89 nissan centra, when I stop, the trans seems to shift itself into neutral, and after I give it some gas, it will violently drop itself into drive with tire chirping. If I go to take off and put the selector in first gear instead of leaving it in drive, it will smoothly put itself into drive, but will grind if I give it too much gas. The trans is leaking and the problems didn't start untill after going through a few quarts. Will it be reliable if I just keep adding fluid and taking it easy on the car? I Thank you for any input.

[Dogrocksee]

RL3R01A
The transmission above is a front wheel drive 3 speed automatic transmission. Shift timing is computer and throttle pressure cable controlled. the throttle pressure cable connects from the transmission to the carburetor or throttle body, depending on the configuration of your engine. Common symptoms are transmission shifting erratic, slipping or not shifting at all.

The throttle pressure cable adjustment should be checked fist, before any major repairs.

Find and repair the leak, the low or over filling of the fluid can damage the tranmission.

[bluevp00]

How many miles since the last fluid change? (if it was ever changed) It's recommended that most cars change trans. fluid every 30K - 50K miles. However, if the fluid hasn't been changed for a really long time, dirt and sludge can build up in the trans, and then get dislodged by the new fluid, sometimes causing harm. In your case, I would recommend just a simple drain and refill, don't do a complete flush yet. If there is an improvement in transmission performance after that, then you can consider a complete flush.