hello im currently replacing all the synchros on my y21 lsd transmission.the
main shaft went on back together smooth so i have that done but on the
countershaft 1st gear is pretty tight. it still spins but you have to twist it
pretty hard. i used a press and made sure 1st gear was free to spin 360 degrees like butter when i torqued down the lock nut at 80lbs [thats what's recomended] everything compressed and 5th gear is now pretty tight but will still spin if you man handle it. so idk if it will just brake loose as soon as it starts running? now second gear... it doesnt spin freely when the synchro sleeve is in neutral. the way 2nd gear synchro is designed makes it where 2nd gear locks up, its not completely locked up it has some spin play but due to the 3 tabs on the synchro, it prevents it from spinning complete 360 degrees. 2nd gear also has 3 craters [thats what im caling them lol] where the tabs on the synchro will sit. sounds confusing but im just curious if 2nd is suppose to spin like the other 4 gears? ive been following the service manual and unfortunetly it isnt very clear. also what does 80 - 0 -80 lbs trq mean? any help on this will be appreciated. i hope i get an answer soon.

 

Did you assemble it wet or dry? The synchros cannot be installed dry. Did you line up the friction dampers? 80-0-80 Means you torque it, fully loosen the nut and torque it again.

 

I lubed it with synchro mesh, took it all apart. Added hella fluid and let them soak for about 10 min. And now everything spins how it's suppose to. Im upgrading to supertech carbon synchros so they were pretty dry and tight compared to brass. Everything is good now! Thanks alot man!

 

You're welcome.