Ok, my 07 GT 5-speed has 40k miles and I'd like to replace the tranny fluid with a synthetic fluid. I've read good results with Redline D4 ATF and also Redline High-Temp ATF. Price difference is negligible. Any comments on which would be better? I live in Socal where outside temps do get to 95-100F a few weeks out of the year.

 

amsoil and royal purple. look at those

 

Take a look at the stock Motorcraft ATF that came in the car from the factory. I believe it is also fully synthetic.

 

Royal Purple Synchromax FTW

 

i hurt my trans powershifting the first year i had it...put up with a balky second gear for about a year...someone suggested royal purple synchromax, figured what the heck- IMMEDIATELY 3rd seemed like it just fell into place, never missed it since, and within a hour of driving my second gear lockout/grind issue went away.

maybe others are better than stock too, but I'm sticking with the RP as i know for certain it does work. original fluid had like 10k on it, and was still looking clean as new when it came out, but the tranny didnt work very well with it. I'm sold on RP.

 

I had a similar experience with royal purple. I'm sure that there are others that are good but royal purple made my shifts smoother.

 

where can I find the Royal Purple Synchromax?

 

retract that, I thought it was a special order type. I see our local Advanced Auto has it. Off to the store than.

 

Changed out to Redline D4 about 7000 miles ago. Made a big difference when the trans is hot, a lot less whine and shifts better.

 

Remember to slightly underfill according to the manual.

 

Getting ready to get some of the Royal Purple Synchromax, how much is needed for our transmissions?

 

3.2 quarts I believe is the listed capacity.

 

Wow, so 4 quarts at $14-15 a qt for the Royal Purple is over $60 with tax and/or shipping. Oh well, gotta bite the bullet I guess.