transmission fluid.......
 

I have about 143k on my 3400 alero. the trans fluid was changed around 70k. I go to a tech school and wanted to do a flush in my auto trans class and the instructor is refusing to allow me to do it. he says that theres a chance that the trans could fail after the flush. anyone have any advice? I still think it could use new fluid if not a flush might just take it to a shop and have it done. fluid is brownish not burnt lookin. thanks

there is a chance that a transmission flushes could cause trans failure, which is why almost no one does it. they just swap a new tranny in if something's wrong with this one.

that being said, i don't know jack about transmissions, just others' word

Flushing quite often does more harm than good and is not necessary.

No auto manufacturer recommends or schedules flushes of any kind for the life of the vehicle that I am aware of.

Just tell him you want to change the fluid and filter.

That a whole new story ;)

Question for you "car geeks". The machine that hooks into your tranny coolant lines, and then you run the car, and the old fluid is removed, and new fluid replaced, is this called a "flush", or is this just changing the fluid? I am confused. If it is just "changing the fluid", then what exactly is a "flush" (and don't say five cards of the same suit!!) :lol:

That's a "change", just done the easy way. A "flush" is when they drop in chemical additives that eat all the sludge and residue off the inside of all the surfaces. This is the bad thing. Some people's clutch disks are well worn, and the residue and particles are the only thing left in the transmission helping to get friction. That's why trans flush is not recommended.

I would just have it drained, filter changed, and then refilled with Dextron IV or better. Don't waste your money on Redline or Royal Purple, unless you're gonna full-race that bad boy. And I don't recommend full synthetic on a high-mileage trans either.

Is it the same thing for Manual trannys? Do they need an oil change at some point?

No, not really the same. Manual trannies don't rely on internal clutches and bands, valves and all that other bullshit. basically with manuals, you have to worry about synchros which really aren't affected the same way. Yes, they need an "oil change" at some point, but check with the manual guys on how frequently it's recommended.

I know there is no dipstick for the tranny on my car, but I was wondering about the oil in that thing.

Also, I heard that once the synchro are shot, you're better off changing the tranny.

I have a car with 164,000 miles on it. Bought it new in 1995. It still has it's original automatic transmission fluid in it, and the transmission still works just fine. I also suspect that the dirt is holding it togather.

Yeah I have to agree. I flushed my tranny and a few weeks later I blew it up. I was launching it too hard at the track thou.

Manuals don't need a flush, the fliud is more like a gear lube than anything else

Actually, it takes the same fluid as the automatic. (dexron III, don't use Dexron VI in the manual trans though

True. supposedly the propery way to flush an automatic transmission that's way overdue is to just change the filter and filter. then drive it for a month or so and drain out a few quarts more and replace with new. Do this enough times over a period of several months. Some cars even have drain plugs for this.