Manual trans fluid?

Just finished reassemling my sag 4 speed.
What gear oil should I use? weight, synthetic? Brands you guys are happy with, etc.
Thanks as usual

 

For smooth slick shifts you cant go past Auto trans fluid. been using it for years.

 

yeah but he has a manual. i dont think atf is thick enough. sorry i really dont have any suggestions on the best gear oil. i'm cheap i just use what ever is cheapest. usually in a sae 80-90 good luck

 

Atf

 

Go to Auto Zone and look in an Oldsmobile Haynes manual, I think some of the 70's Cutlasses came with Saginaws (I think they were 3 speeds though) Off the top of my head, I think they take Sae 80-90 or something super thick like that. I think I used valvoline SAE90 in my '62 E-100, worked for me.

 

i use 140wt in my 51 shoebox trans and rearend. i get it from napa. sta lube i think is the brand

 

I'm a big fan of LE Engineerings oils. http://www.le-inc.com/ a 75w90 should do the trick....

 

Thanks guys

 

I use M1 synthetic for most of my stuff, particularly if its a fresh rebuild with no leaky seals(which typycally leak faster with a synthetic)

 

Mopars used atf in their NP-833's...

 

Yes! Factory recommendation.

 

75-90 full synthetic

 

Mercedes-Benz has used ATF in their manual transmissions ever since I can remember(I started working for an M-B dealer in 1972).If you put standard gear oil(80-90w)they wouldn't shift.

 

Just a note to go bit further. Most of the older saginaw trannies are set-up and/or designed to use 75-90w gear oil. ATF is significantly lighter and does not have the sheer strength of the gear oil. Now if a tranny is
designed/set-up to use ATF that's one thing but to just put it in a situation that it is not designed/set-up for is an entirely different thing. It's just plain shitty advice. I hope you guys don't give the same kind of advice about motor oils as well...