Today I drained my 1989 S10 Blazer's 5 speed manual transmission. I expected tranny fluid to pour out, but it looked and smelled like 80w90 gear oil.

My questions are, Have any of you had to deal with this before? What do you suggest I refill it with?

Thanks for the advice in advance.

 

Manual transmissions take gear oil, something around 75/90

 

Thanks Vada

The book said to use automatic transmission fluid, didn't mention gear oil. That left me feeling alone and isolated.
Thanks again for bringing me back.

 

What book are you using?!? Only automatics take ATF.

 

Haynes and Chilton both agreed, Dexron II ATF for these maual transmissions.

Mine are older books, have they been reprinted with the correct information?

 

I don't have the specs for your vehicle year, but it is certainly not unknown for a manufacturer to spec ATF in a manual transmission.

 

I asked an oldskooler at the auto parts store what he thought. He suggested the previous owner put gear oil in there to reduce noise, and I should run it with ATF to flush it out before draining and refilling with ATF.
I think this is what I will end up doing tonight after it cools down out there.

 

It really comes down to which transmission you have in your truck.

There were two 5-speed manual transmissions available:
Warner T-5 - Dexron II ATF
Muncie 5LM60 - Synchromesh Trans Fluid T2850

 

I never trust what the haynes or chilton books say two seperate autos and they are wrong on amount and type of a few fluids.

 

I chickened out, I wanted to take more time to think this through, going to ask the guys at work tomorrow.

Thankyou Kyle for mentioning Synchromesh Trans Fluid T2850, this is the first time I have heard of it. Is it likely I could have mistaken this fluid for gear oil? I have been searching for a stamp mark to identify the tranny, I would like to know if it is the Muncie 5LM60.

thanks again, have a good night