I currently have a CD009 transmission and I am experiencing issues going into 3rd gear. When it's cold, it goes in just fine but when warmed up it grinds really bad. At high RPM it has major grinding issues. Every other gear is fine just wondering if anyone has any insights before I condemn the syncros.

 

Have you changed your fluid?

 

Yes did that today with redline mt-90 same issues

 

Sounds like a syncro to me. Higher RPM's, faster it would be spinning, if the teeth are ground down on the syncro then they won't catch as easy at higher revs. Specifically in 3rd to indicates that to me. but before we go that route, how many miles on the trans? new clutch? Have you tried bleeding the clutch at all to release and residual air (PITA). it honestly sounds like syncros to me but can't be sure until you tear it down.

 

MT90 is a bit heavy for our gearboxes. MT85 is the right viscosity for factory specs.