I bought an MGW a few days ago and I will be installing it sometime this week. I figured that I might as well change out the tranny fluid while I have the shifter off.

What type of fluid should I use?

I have heard Dexron III or ATF, but aren't those auto tranny fluids?

I also saw Mobil 1 ATF that said Dexron III on it. I am so confused...

 

yes our cars take atf. RP doesmakes something specialy for the tremec's i think though. I used RP atf, smoothed everything out alot.

 

Weird but I guess I wil be using that. On cold starts, the first shift into second is hard to get in sometimes. I figured putting in the lower amount (3.2 Liters) would help out a bit.

 

RP atf= Royal purple?

 

Yup

 

tranny fliiud is some $$$$

 

RP or Synchromesh synthetic

 

Will lowering the fluid level and changing it to something different help with a 1-2 gear shift issue?

 

Yup.

 

I used to have a 2003 GT (has the same tranny as the mach1) and remember seeing threads about a Tremec 3650 TSB about using less fluid (3qts instead of 4qts) to prevent stress on the gears (it was described as trying to run through knee high water if that makes sense). Anyway, here is a link to a page where someone talks about this issue at length:

http://www.bullittarchive.com/1023.htm

I tried to find a link to the actual TSB but couldn't find it. Hope that helps.