margarita

Hi All, Can someone tell me if there is a difference between just draining the transmission fluid and doing a transmission 'flush'? If so, what is the difference? Any idea in average costs? I need to get this done soon. Thanks for your feedback.

rob22

I don't know the specifics of a flush but I've been taught just to drain/refill. How many miles on the tranny and have you ever changed the tranny filter?

Rob

mista808

well our transmissions hold about 12qts of fluid. when u drain, only about 2.5qts drain out... I don't feel like doing the math but that's only about 20%. You would have to drain and refill about 6 times for all new fluid to get in there. BUT everytime you drain and refill with new fluid, you're mixing it with the old fluid that was already in there. I recommend a complete flush so you know all new fluid is getting in there. Its simple, there's a tutorial at lexls.com. but also, for added measure change out the trans filter, put the pan back, add fluid, then do a flush.... did it to my lux, and it shifts so much smoother......

margarita

thank you both.

well, good thing I read up. it's exhausting, but i find if i know how to do something before i have someone else do the actual work, that it always pays off.

there are different ways of doing a flush, and the one using a machine that pumps fluid through using pressure would be the wrong move, especially for an older engine. all is explained at these links. there's a better way...or, i can just skip it and drain instead.

http://www.lexls.com/tutorials/trans...anschange.html
http://www.lexls.com/tutorials/trans...ransflush.html

Bradster

I did a complete flush @ Lexus dealership when i got my 90 LS400 with 225K...No problems at all...These trannys are bullet proof!

MEANDAFAKA

i just changed out my tranny filter, new gasket for the pan, cleaned out the magnets inside the pan, and new fluid. but i will do a cople more drain and fill.

GSteg

iTrader: (15)

Do drain/refill to maintain the freshness of fluid in the tranmission. Do a flush if your fluid is old/dirty.

atoyot

i have no idea if it's true or not, but i have been told not to do a flush. Supposedly "if" there are particles or gunk in the transmission, the flush could dislodge them and leave them in the tranny. Again, i don't really believe this considering you have a filter in the tranny and the point of the flush is to FLUSH all the fluid out. Anyways, these mechanic's logic were that if particles were in there that they were sitting in places "out of the way". If you flush you are just putting them back into the tranny.

i take that with a grain of salt, but i have heard that.

margarita

thanks. about 90K miles on it and fluid was changed out (not flushed) about a year ago. i do mostly about town driving, so few miles (less than 5K) on it since then. the fluid is a cherry red. i was told it was dirty. the red isn't real clear...more of a deeper red? i think it should look clearer than it does. maybe just drain all of it out by that non-machine method described in one of the links, replace gasket and screen/filter, clean pan and magnets. that should do it. thanks all...

GSteg

iTrader: (15)

You may not even need to replace the 'filter'. It's just a metal screen and most of the time when people take it out, it's free of debris anyways. I'd just do a drain and refill for now and see how that goes. Cherry red isn't as bad as other cars I've done. Many cars had brown fluid.

nthach

That happens if a flush chemical was added to the tranny - I know BG, MOC, and MotorVac sell such additives which is nothing but stoddard solvent(tech name for mineral spirits or any petroleum solvent with a moderate to high flash point), 2-butoxyethanol which is found in 409, WD-40 and glass cleaner, and various petroleum solvents and alcohols.

I'd do several drain and fills with T-IV. Sure, you could use a "universal" ATF such as Valvoline MaxLife, but from my experience with it on a Honda don't bother.

margarita

great. i'll ask them to just clean the screen then. as long a they have to open it up to do the pan gasket, i want to make sure everything else gets cleaned properly.

GSteg

iTrader: (15)

Well I dont think you can clean the screen itself. I believe the screen is enclosed in a metal filter housing. Most cars have these kinds of filters. But if the pan is going to be taken off, you might as well replace the filter just so you can say you did

PureDrifter

iTrader: (10)

you can rinse the screen out after you take it out with a goody amount of brake/carb cleaner.

MEANDAFAKA

WTF, the god damn filter with the gasket is like 20 dollars. why are everybody want to just clean the screen?? autozone, napa, and any other store sell the filter kit which include the csreen, and gasket for ONLY 20 dollars. go do it right, and stop being cheap.