saginaw oil

[motorsports12]

what gear oil is best to run in a Saginaw for a 1/2 mile dirt track

[ric78]

automatic transmission fluid

[JustAddDirt]

automatic transmission fluid

I think that depends on what bearings are in it doesn't it.
I would think you would need 75/90 gear oil for most units.

[ric78]

Just a stock saginaw 3 speed we have ran them with just ATF for years never a problem. A transmission run through high gear does not generate enough heat to hurt anything.

[powerslide]

Don't you need the GL rated stuff for the brass synchros? I think its a gl-4 if my memory hasn't failed me. Or are you saying because its not shifted much you don't need that?

[ric78]

Never looked at that just used a good name brand. Years ago I was mixing it half gear oil half ATF. Then just decided to try straight ATF and never looked back. Maybe we were just lucky. All I know is for five years the only trans problem we ever encountered was a broken ear.

[95shaw]

Synchros actually like the atf better. shift quality may suffer with 80/90. As if that were a concern in our app. Have ran same oil as engine with no problems. Currently running 85/140 same as diff after learning from oil supplier that 15w40 and 80/90 start from same base oil. additive only difference. 12th year on same trans. Biggest thing is keep some in there. with atf and engine oil, cheap insurance to change same as engine.

[stockcar5]

Synthetic ATF in anything from a stock unit to one built with ceramic bearings. I prefer Dexron hp.