I was reading some old posts and am now very confused. I know there is a dipstick in the front which we checked and found to be low on oil so we added 90 wt. I am now reading that there is a second fill plug in the back differential? Could someone please explain this all to me? I just got another transmission, but before we replace it I would like some more information about the oil requirements. It's a '78 Brat with 4 speed manual transmission.

Thanks!

The rear dif is separate from the transmission, and both use 90 weight oil.

The fill plug on the rear dif is also where you check it.

Remove the plug and stick you little finger in. The fluid should come to the top of the fill plug hole. Add fluid till it runs out.

Be sure you're on level ground.

I like the new full synthetic oils, especially for tranys and difs.

I recommend changing the old fluid for new. Flush with your favorite slick-um to get out any accumulated crud.

Since you're changing the trany, be sure to put new seals in at the axles, and any place else they look wet. It'll be much easier with the trany out.

Would you, Could you explain the "flush" procedure. The only way I can describe my tranny fluid is RANCID. 

Should add, I'm in the wrong forum now (have a 78 Brat) but was looking for manual trans discussions. 

Edited April 15, 201411 yr by CMJAnew