My friend and I have just rebuilt my lsvtec and this time I decided to go with an Exedy stage one clutch and an Exedy lightweight flywheel. Before that I had a stock ls clutch and flywheel and 4th gear grinded a little bit, only when I was seriously getting on it. Now, I grind 4th gear when RPMs in 3rd are 3000 and over. Anything under 3000 going into 4th its fine. But....when I get up there in 3rd gear and put the clutch in, put the shifter in 5th and back to 4th, theres no grindage at all. Im guessing my 4th gear synchros are thrashed. I was thinking about trying penzoil synchromesh, or is this a waste of time and money? Im already trying to find another tranny so I can yank mine out and see whats up with it, but i need to keep driving it until i can get one, so if theres any "quick fixs" i could try please let me know. Oh BTW my tranny is a cable GSR.

 

Lots of people on 8th civic swear that changing to some kind of aftermarket gear oil fixes 3rd gear grind. I don't see why it wouldn't work for you.

 

Ok well i guess i should try penzoil synchromesh. I will let yall know the results...

 

I think it's the GM syncromesh friction modified you're looking for. idk if the penzoil one is the same.

 

Ok thanks