I just really want to upgrade to 4.11 final drive, gears are way too short. But I'm nervous to have the trans built just to have 5th gear start to grind again, that would really **** me off.

 

Check and recheck everything on your first teat drive after a full rebuild. Properly bleed the clutch, adjust the clutch, proper fluid levels, etc. Mine was grinding 5th so bad that I had to replace the gear. Ever since the rebuild I haven't had an issue with 5th. It's a much better transition from 4th to 5th but it's still a pretty decent drop. I always try to rev match my shifts. And I shift REAL easy while the drivetrain is still warming up.

 

Unless your running a stroker there is no need for the 4.11 final drive.

 

the evo 8 4th with the evo 9 5th will reduce some of the syncro issues as it lessens the differential between them, but it will not solve all 4-5 issues, nothing will. i do think its a good idea to slow the shift down a little and dont use too slick of a gear lube. syncros need some friction to work.