5th Gear Grind

[fabbio25]

I heard this mentioned here before but coiuldnt find anything in search. Just had a z1 shortshifter installed and now i get a grind when shifting into 5th gear. This only happens at higher rpms. Anybody know what this is and how to fix it.

[NissanFairladyZ32]

Rebuild your transmission, it sounds like the syncros are shot

[BigTDogg (MA)]

What clutch do you have? What transmission fluid and when was it changed last?

[fabbio25]

Specialty Z sport street and supposidly the transmission fluid was changed last year with redline.

[fabbio25]

Rebuild your transmission, it sounds like the syncros are shot

The transmission was rebuilt at 60,000. The car has 110,000 now.

[BigTDogg (MA)]

Redline what? MTL is too thin, IMHO for our synchros. MT-90 will help ease the transmission grind.

A solid clutch fork may also help, but I'd start by adjusting your clutch.

[fabbio25]

Im gonna change the transmission fluid this week just to make sure. I'll use the MT-90. I just think its weird that the grind started when I had the short shifter installed.

[BigTDogg (MA)]

Short shifters are harder on the syncros usually due to the driver getting used to the shorter amount of time it takes to get into gear. I always shift easily into 5th, because if I'm up at 5 or 6K RPM in 4th, I'm already going plenty fast so there's no rush to get into 5th

Rev-matching will also help your synchro life.

Fluid flushes and cast iron clutch forks will help, but the only way to repair a worn synchro is to rebuild the transmission.

[fabbio25]

Thanks Big and yes you are right when i shift easily into 5th no grind. So its prob just my pyshco shifts that were causing the grind. Im gonna do a transmission flush anyway.