Probably a 5th gear syncro. Mine went out with 138 original miles. Driving like a granny was fine, but anytime you shifted with any enthusiasm at all 4-5th gear it would make a quick grind sound. Mine was covered under warranty fortunately, because it happened twice within the first 1000 miles.

 

I don't recommend the royal purple lubricants, they don't hold up long enough to make it between the recommended oil change interval. I use Penzoil Synchromesh in the transmission and Diaqueen from the dealer or vendor in the transfer case and rear end. The only problem I've ever had was the high rpm 5th gear grind but that is actually pretty common in our transmissions. Mine started grinding before I changed to the Synchromesh and had always used factory fluids. Let me know if I can help.

Josh

 

^+1 That is a good fluid combo. IF it is the 5th gear synchro I'd just rreplace it when you replace your clutch. It sounds like you should be good with fluids and synchro fix. you won't lose here

 

so the royal purple all the way around 75w90 isnt a good idea?

 

sounds like TC which sucks lol

 

nah, either the penzoil or amsoil for the transmission. and use the diaqueen for the tcase. ALso, please make sure you have an even tires same tread etc. This is not to be joked with, because the tcase is not cheap.

 

so i guess i just can understand why a full synthetic wouldnt be better than stock stuff?

 

GL5 is too "slippery" for the Evo 5mt syncros, it actually ends up burning them out faster. Try redline mt90 gl4 or amsoil 75-90gl4.
Also 03 with a single disk clutch... If it's ACT, your probably already screwed, I have seen soo many of those clutches eat transmissions due to their BS release issues (including my first tranny).

 

ok i see ill put some gl-4 gm synchromesh **** in the tranny... and use the royal purple in the rear end and t/c?