my buddy had me replace the synchro's n his gsr tranny, after gtting it back n the car with brand new synchro's every gear shifts fine except reverse.....it goes in but then pops back out, will only stay in if you hold it in. ive never dealt with this problem n was trying to find out what could cause this? any help is greatly appreciated

 

thrust clearance? detent *****?

 

i put everything back just like it was, he had noissues before other than grinding going to second. could it be a result of the synchros breaking in? he also is using two quarts of gm synchromesh, shouldnt b the problem right?

 

Sounds like something isn't back together just like it was, or something was damaged and you just weren't looking for that particular problem with reverse. You need to pull it apart again and take another look - you'll find that not too many people run into reverse issues. Only problems I've seen are the reverse idler gear's bushing too loose and it bobbled on the shaft, or the idler gear itself fused to the shaft. Which your problem won't be the latter that I mentioned.

 

If it didn't do it before, it wasn't reassembled correctly. If it did it before, you missed a damaged part.

Lose the Synchromesh.

 

make sure the fluid level is correct.

 

I always run pennzoil 10w30 motor oil but he wanted to use the synchro mesh, he said it wasn't doin it before but I didn't drive it so I don't know if it was or not. Anyone have a pic of what the countershaft should look like? Maybe I installed the reverse gear upside down?

 

Does it go on with the teeth side of the gear down or up?

 

Down.

 

Now he says it wasn't doing it right after I put it in didn't start doing it till a week later. He was havin some clutch cylinder issues when he left my shop but said he has all that worked out now,