Transmission fluid change

[Franklinprc]

Anyone has any idea how offen should have a transimission fluid change?

[SomeGuy]

Auto or manual?

[Franklinprc]

Auto

[Hotsky]

First time I changed mine was around ~145K :blush ....manual doesn't say anything about changing the fluid. If I bought a new car I'd probably change it every 50K.

[Booter22]

average we went by
Manual, every 48k or 2 years
Auto, every 60k or 3 years

unless it becomes black and smells burnt before hand, which did happen very often.

[TheMAN]

change every 50k is a good general rule of thumb/nice round number, on any car, any type of transmission
if you have flushed an auto completely out with synthetic, then you might be able to go twice that or more... you'll need to inspect the fluid after those 50k periodically to see
manual, you can go a very long time once you switch to synthetic

[r4BBiT]

average we went by
Manual, every 48k or 2 years
Auto, every 60k or 3 years

unless it becomes black and smells burnt before hand, which did happen very often.

Maybe I missing something, but changing manual gearbox oil sooner than automatic does not make sense to me. Those are fully sealed units so unless you are constantly grinding gears to me that's way to early and total waste of money. My car is 4.5 years old with 50k on it and there is and I'm still on original gearbox oil. I'm not a mechanic though.

[Booter22]

Maybe I missing something, but changing manual gearbox oil sooner than automatic does not make sense to me. Those are fully sealed units so unless you are constantly grinding gears to me that's way to early and total waste of money. My car is 4.5 years old with 50k on it and there is and I'm still on original gearbox oil. I'm not a mechanic though.

Of course they are sealed. Or they would leak all over the place.. lol. But why the manual wears down faster then an auto. No idea. Maybe something with the driver control of the shifting vs it being done by a program wears more. Who knows.

[DLYDRVN]

AFAIK Auto and Manual trannys use the fluid in almost totally different ways. With Manual it's mainly for lubrication and friction control (synchs etc...) with auto it's part of the sort of pseudo-hydraulic system that the transmission functions with.

From Wiki:
ATF:
"The fluid is optimized for the special requirements of a transmission, such as valve operation, brake band friction and the torque converter as well as gear lubrication. Despite popular parlance, ATF is not an oil."

MTF:
"Manual transmissions are lubricated with gear oil or engine oil in some cars, which must be changed periodically in some cars, although not as frequently as the automatic transmission fluid in a vehicle so equipped."


So the primary difference in the intervals is because the fluids and mechanisms are actually in no way similar to each other. However wiki suggests that MTF is changed LESS frequently than ATF.

[Booter22]

AFAIK Auto and Manual trannys use the fluid in almost totally different ways. With Manual it's mainly for lubrication and friction control (synchs etc...) with auto it's part of the sort of pseudo-hydraulic system that the transmission functions with.

From Wiki:
ATF:
"The fluid is optimized for the special requirements of a transmission, such as valve operation, brake band friction and the torque converter as well as gear lubrication. Despite popular parlance, ATF is not an oil."

MTF:
"Manual transmissions are lubricated with gear oil or engine oil in some cars, which must be changed periodically in some cars, although not as frequently as the automatic transmission fluid in a vehicle so equipped."


So the primary difference in the intervals is because the fluids and mechanisms are actually in no way similar to each other. However wiki suggests that MTF is changed LESS frequently than ATF.

but we all know how you tm3ers drive race cars.. ;) so should be done before on the MTF. most of you own manuals right? who mods an autobox anyway.. :loco:rolleyes

KIDDING!

but thanks for the info its good to know the differences in the actually fluid make up. i honestly didnt think about it that way. now where is someone to say that you never need to change it.. :bang i remember someone saying it was sealed and not exposed to heat so because of that it was less likely to wear and break down.. if only i could find the post. sure was good for a laugh.. whats the big thing the transmissions hooked up to that gets really really hot?.... the engine... right? :P

at the end of the day over maint kicks under maints butt anyday. so doing it earlier then later could save you a large repair bill, and if not is peace of mind

[rajin929]

i'll probably get flamed for this, but I just drain and re-fill the 3 litres of ATF in the pan in the spring and again in he fall.
usually time it with an oil change since the car will be up and undercover is already off.
The ATF fluid always come out dark brown and dirty lol

I DIY so no cost to me other then the fluid.

I should do a full flush through the cooler line and re-fill and just leave it for the proper interval, but meh some fresh fluid more often can't hurt I guess lol

[TheMAN]

drain and fill works fine if you haven't wasted money on synthetic
if you are going to synthetic, flush it out the first time and you're ok with drain & fill with the same stuff afterwards

for manuals, the reason to change it is to get rid of the wear metals and any broken down oil... extreme pressures and stresses causes the oil to shear down which will cause additional wear to components such as bearings.... the thinner oil causes parts to run hotter, and heat kills bearings faster than gears..... this is also another reason why synthetics are so much better because they resist abuse much better and due to their already improved lubricity, they allow parts to run cooler from the start