Which trans fluid to use in my 5-speed?

[daddystang]

I bought a Super HD T-5 from Summit last summer which says Tremec on the body of it, and there was a tag on it that said "this transmission must be filled with ATF". I filled it with ATF synthetic Castrol. It seems to be ok, and shifts good though a little noisy at times. The reason I'm asking is a friend told me I was crazy for using automatic trans fluid in a 5-speed, and said I should use the manual trans fluid. Any one know for sure which I should be using? Thanks guys, just want to make sure I'm doing things correctly.

Thanks in advance....

 

[Shamus O'toole]

Your friend knows nothing about T-5's. You have to use ATF in them.

 

[1red95gt]

+1

 

[Blown331LX]

Your friend is an idiot, not only use ATF but use Mercon V it superseeds the factory used Mercon III. If you use gear oil you will melt that T-5, its not thin enough nor can it cool properly.

 

[daddystang]

Thanks guys, I appreciate the responses. You are right, he is a knuckle head.

Thanks again.

 

[ebk06]

GM synchro mesh FTW!!!!! Its about $15 a quart but its better han anything else for a T-5.

 

[Darkwriter77]

Mobil 1 fully-synthetic ATF would also be a good alternative, since Mercon V is only a synthetic blend (instead of 100% synthetic). Might last ya' a bit longer, as it seems to hold up better against thermal breakdown over time.

 

[Mustang5L5]

GM synchro mesh FTW!!!!! Its about $15 a quart but its better han anything else for a T-5.

Tremec recommends to avoid GM synchromesh in a T-5. It tends to cause the blocker rings to slightly swell. Makes the shifting feel nice but will prematurely wear them down

 

[Deleted member 87397]

Royal Purple Synchromax or
Redline D4 ATF

 

[jimdrechsler]

how many quarts does it take to fill her up?

thanks,
jim

 

[HISSIN50]

how many quarts does it take to fill her up?

thanks,
jim

Just under 3 quarts. 2.6-2.7 should do it.