Mazda Trans. oil type

[Clifford]

I have a 1990 Mazda B2200 I bought it with 50000 miles on it. It shifted hard so I put ATF Dexron in it and it shifted better. When it had about 80000 miles on it would not stay in 2nd gear so I took it part and found that the fork wore out. After replacing the fork I put Dello 15-40 in it but now with winter here it's shifting hard agin it has 96000 on it. Now I put 70-85 in it like the book says but its shifting hard 1st. to 2nd. what type oil should I be using?

 

[Dick in Falls Church]

Use a synthetic 75W-90 gear lube. AMSOIL comes to mind, or Mobil 1, or ---

 

[unDummy]

MT90....

 

[Clifford]

I put Redline MT-90 in the trans and I can't believe the differance shifts great.
Thanks