I’ve got a Mitsubishi FM 146 5 speed tranny that was just recently rebuilt. All the components are new. Installed the tranny the first time and third gear wasn’t smooth. Would have a bite going into third and would grind down shifting back to third. Took the tranny out and replaced the third gear synchro. Put everything back together. Same story, not as bad, but still has a bite going into third and now into fourth, and can not get it to down shift into third without grinding unless I perfectly rev match. At that point I’m not even using the synchro. Everything is new, synchros and gears, and I am at a loss. Any pointers, advice, or places to start would be helpful at this time? Thanks.

No input?

what are you using for fluid?

Royal Purple 80-90wt

i run regular 90wt in mine too and it shifts okay. a buddy of mine runs motor oil in his and says it shifts way better. i think 20wt. doubt that is the root of your problem, but it may be worth a shot.

Yeah, a bit more serious than just a change of fluids. Grind in third and fourth. Both new gears. How about this for you guys. Keeps chewing the pocket bearing between the input and output. Does it within 500 miles. Space between gear and synchro areall within spec, still driving me nuts. About ready to dump this and get a new reman. Any other ideas?

Yeah, a bit more serious than just a change of fluids. Grind in third and fourth. Both new gears. How about this for you guys. Keeps chewing the pocket bearing between the input and output. Does it within 500 miles. Space between gear and synchro areall within spec, still driving me nuts. About ready to dump this and get a new reman. Any other ideas?

sound liek a good time to get a M50D for in that pig.

Is the bellhousing on it straight? Trans fully seated to the engine?

I dunno, I'd 2nd NetBSD's advice on the Mazda M5OD. The Mitsubishi is garbage.