I know a lot of 6MT people have been bitching about our synchros being pieces of sh**, especially on 1-2 and 2-3. I dunno, maybe it's just the 9 months and 9K of driving, but 1-2 has actually gotten smoother for me. That shift used to slam/clunk and even grind at 2K+ miles. And I'm still using non-synthetic in the tranny. I didn't even use the clutch on 2-3 and 3-4 on the drive home tonight.

Maybe I just felt like bragging about that. happy shifting.


Drew
2003 G35 Sedan 6MT / Black / Graphite / Prem / Aero

 

Wow- that's great news- gives me hope. I've had my '04 Sedan at the dealer 5 times so far for the 1-2 shift problem. Transmission replaced, revised clutch and push rod, still not shifting well at 4K miles. Even had a nissan specialist look at it. Ready to pursue lemon law and get money back given the attempts to repair.

If I knew it would really get better with wear, I'd reconsider cuz I can't think of an upscale manual trans car I'd rather have...

'04 G35S 6MT

 

I had the same issues with 1st to 2nd gears. I put half a bottle of prolong engine treatment in and it was gone. Give it a couple of days. Don't want everyone to now go out and buy it ,but we just need another to verify findings. Found it cheaper at Pepboys, but here is the site if you want to check it out.

http://www.prolong.com

 

Good info, Praztek.

My 6MT has almost 3,000 miles now, and the shifts seem to be getting smoother, but it still feels pretty "notchy" to me, and I've noticed that the synchro from 1st to 2nd is a little slow as compared to my other MT's, past and present.

Had the same problem in an '86 Mazda pickup (even after a fresh rebuild with a factory kit), and swapping Redline Oil Synthetic MT Fluid sped those synchros right up, and cured the problem.

Your Prolong solution is a simpler fix - interested in how it works for others. Anyone who uses Prolong, please post your results.

Sport Sedan Fan
2004 6MT Sedan/Sport/Navigation/Premium/Aero

 

Well mine is going in Tueday for this problem and I have 7k of miles. It did get better but not better enough personally.

2004 Infiniti G35S, 6MT, Premium, Sport, DP
Mods: JDM Clears, 20% tint, Z-tube, K&N Drop In
Track: 14.32 at 97.6 mph 2.196 60ft (1900 miles bone stock, with bogging)