Sticky: 370Z Transmission Failures (6MT)

Spartan 1771

I know this is an old thread, but I figured I would give it a shot.
I'm the original owner of my 2009 Z, which has a manual transmission. The car only has 24,000 miles on it. It doesn't have the sports package, so no synchro-rev trans and I’ve been using Red Line fluid for the past 14,000 miles. I believe the 6th gear synchro is shot. When powering through the gears under WOT it will grind going from 5th to 6th. If I power from 1st through 5th but then press the clutch, wait a second and then put it in to 6th, it won't grind. So like I said, sounds like the synchro to me. Correct me if I’m wrong. It’s been doing this for about 18 months, but the car is my weekend / summer car, so I haven’t been too concerned with it. In the mean time I have been squirreling away transmission parts for the inevitable repair. I’ve accumulated just about everything I want:

Z1 Parts:
Clutch, unsprung hub, lightweight flywheel, CSC elimination kit, steel braided clutch line and transmission mount.

I also have a set of Mtec shifter springs and an RJM clutch pedal. The only thing left to get is the RJM clutch master cylinder and the synchros. The car already has a B&M short throw shifter installed.

I spoke with someone at MA Motorsports earlier today about this repair and the installation of the mods. According to them: “Most of the time we suggest just replacing the entire transmission to be honest. The work to repair the gearbox is very time consuming and you still have a mostly used gearbox at the end of the day. For only a little bit more we can sell you a whole new transmission from Nissan (in most cases).”

Although MA Motorsports came highly recommended, has great ratings and appears to be trustworthy, I still have to question this, especially since the car has so few miles on it. I’m not one to cheap out on my car, so if this is necessary, I will go through with it, but I don’t want to waste money. Unfortunately for me, the car is WAY out of the warranty period, so the bill is on me.

Although I have done all of the work on my Z thus far, transmission work is WAY out of my comfort zone, so that’s not an option for me.

Thoughts, suggestions, ideas?

__________________
~Rob

-DD Air Guide, Stillen G3 CAIs, 63mm Throttle Bodies, Motordyne M370, Berk HFCs, FI TDX CBE (non-res, CF), Sprint booster v3, Ecutek Dyno Tuned, and the list goes on...

Rusty

You would be better off with a new tranny. There was one guy rebuilding them with better parts. But haven't heard anything about him for about a year now. So I don't know if if he is still doing them or not. He was a bit pricey too.

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浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html

Whjaxn17

Level 10?

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377whp/299wtq NA
704whp/519wtq, SOHO stage 2.5
IG: pearlywhite.z

Rusty

Don't they just do auto's? Never heard of them doing manuals.

__________________

浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html

Whjaxn17

I have no idea. I just had seen the name floating around and was asking if that was the shop you meant that you hadn't seen/heard about in a while.

__________________
377whp/299wtq NA
704whp/519wtq, SOHO stage 2.5
IG: pearlywhite.z

Rusty

It was a member on here that was doing them.

__________________

浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html

vman12

I have a 2014 370z manual with 30k miles. I had my transmission replaced this summer. I had the car for about 3 months and one morning i started noticing that it's getting really hard shifting into 6th gear (no noise just hard to go in). I made an appointment with the dealer. That afternoon driving to the dealer on the freeway i couldn't get the car into 6th at all. It was like hitting a wall, no matter how i tried to push it in. Tried going from 5th to 6th, from 4th to 6th, just wouldn't go in. Dropped it off at the dealer. Dealer test drove on the streets, came back said it was fine. I went with the technician and wanted him to show me how it was fine. In the parking lot we just sat with car off and changed gears. All 5 gears went in easy, you could almost use your pinky finger to push the the stick into gear. But 6th wouldn't go in. So he just grabbed it and with all power shoved it in. I told him no way that's how it's supposed to work (this is a japanese car not an old muscle car). It was fine before. Long story short i convinced him to get it replaced under powertrain warranty. They put a new one in, although i gotta say it still feels just a little tough at times going in to 6th (wonder if they put in a refurbished tranny, not a new one). Hey, but at least it works now.