I have a 1984 12a 5spd and I was planning on changing my trans fluid this weekend but the people at NAPA had no idea on what grade of fluid I should use. One guy said he thought it was 5w-30 and another said 80w-90. So I left with nothing. I also live in the pacific northwest and we have pretty moderate temps here. Any help is greatly appreciated.

 

Use 75W-90. You can also use 80W-90... Definitely not 5W-30.

 

5W-30?! Why would he recommend that? SAE 80W-90 is what is recommended in the FSM for my 85'.

 

I just picked up some 75-90 synthetic, works fine.

 

Synthetic in the transmission is the way to go.

 

I usually use 75w-90 enos stuff does the trick for my trannys