The royal purple synchroesh is cheaper than the GM stuff. Has anyone used it? I currently have GM and never used the royal purple. I just wanted to know if was the same quality. Also how much was the (fix) for the tremec's I think it was like 3.2 liters or something like that.
They are basically the same product and depending where you buy them, sometimes the GM is more and sometimes the Royal Purple is more. As far as the correct fill amount, check the stickied item at the top dealing with Tremec issues. Someone in there talks about the proper amount. I can never remember if it's 3.2 litres or 3.2 quarts...
On a happier note it looks like Tremec and Ford may be close to having an actual solution to the problem instead of a quick fix.
After a little searching it turns out that you want 3.2 litres. Keep in mind that not everyone is having success with this fix and that many people are still very unhappy with the Tremec. Hopefully that solution comes quickly! It has actually made me consider getting an auto Mustang when I get one...