those of you with 5 speeds, do you use gear oil or ATF in your manual trannys? i think i asked about a year ago, and the majority told me atf because that is what is recommended. every mechanic i talk to, though, tells me to stick to gear oil because atf is too think and it wont lubricate "hard to reach places" as good as gear oil can. when i bought my truck he tranny was already damaged due to the fact that it was low on fluid (atf), and after i rebuilt it, my mechanic has told me to use gear oil ever since. ive had absolutely no problems, and i was curious to see if any of you guys are using gear oil also. i just want to make sure that im not hurting the tranny in any way (since the recommended is atf)thanks...

 

I use ATF.

Take care,
-Chris

 

On my mechanics recommendation I put in gear oil once. After that it was hard to shift and mileage went down 2 mpg. I drained the tranny and put Mobil 1 synthetic ATF. Now it shifts fine and I get the 15-16mpg I'm used to.

 

ATF in a manual trans? WTF are ya thinking?......lol...90wt is all i've ever used in a manual trans . WTH ATF in the rear end then too?.........lol

 

tahts exactly what my mechanic buddy said. the gear oil isnt giving me any trouble, and my tranny shifts great so i think im just gonna leave it alone for now.

 

since we're on the subject of the manual tranny...how full should I fill it with fluid....till it starts coming out of where I fill it on the side?

 

yeah up to the fill hole. FWIW I use merc 5 in my tranny, it has never had problems and over 200k miles.

 

ok good...wasn't sure cuz thats what I did 20k ago....BTW I just hit 100k in my 96 300ci and still going strong!

 

The service manuals say ATF. My mustang -5spd, had ATF. All saturn manuals use atf. ATF is thinner than gear oil, it also has better cooling properties, and clings better.

I think either will work fine. Some synchronizers have automatic type clutch material on them

Glad yours is fixed Donate

 

Because of the material on the synchros you can't really pick or choose. Use whatever the owners manual says.

-Jon