Hi friends,
So for the past few years my '06 G35 coupe's 6 speed box has been on a downward spiral of whiny gears, noisy throwout bearing, not-so-sporty shifting & a really unpleasant 5th gear. And the clutch has had a stupid high catch point since Jump Street, which is the enemy of fun. Sooo, a week ago I was suddenly unable to engage 5 or 6. I did some research online & found that maybe, just maybe the guide plate beneath the shift boot had become misaligned with the little tab on the right side of the stick, but I adjusted, aligned, no dice. Took to mechanic, and as expected my whole gearbox & clutch= cooked . $2600 later I had a new clutch, resurfaced dual-mass flywheel & a 62k mile transmission w/ 1 yr warranty. I had also asked if he could set the clutch catch point lower which he did. So for a day, I was pleasantly gearjammin almost as smoothly as in my old M3 . Oddly though, 5th gear, again, had an ominous, familiar albeit minor "cha chunk" when engaged. Then the next morning, I couldn't get it into reverse. I had to shut it off, start it in R, and even then shifting into 1st, 2nd, 3rd etc. took the strength of Thor from my skinny arm, and sometimes would be accompanied by the nasty loud grind of errant gear activity. After a few minutes of driving, it would get better but clearly something was very wrong & I had to take it back. The mechanic blamed the main issue on my decision to lower the clutch point (IDK, a lot of people have done this with no problems it seems, and I might add, when I'd requested it he didn't advise against it one bit) but the 5th gear issue appeared to indicate another faulty gearbox so it's back in shop & they ordered another used trans, this one with 54k miles, gratefully covered under warranty. And he did insist on resetting the clutch point back up to factory spec. My questions are these: Is there a common issue with 5th gear going bad or feeling clunky in these cars? Are the 6MT boxes identical in all G35 coupes '03-'07? Mine is the later "sport" generation with the "Rev-Up" VQ35DE engine. What's with the bizarre one-piece "linkage" housing, is it hydraulically actuated like the DSM's (2nd Gen 95-99 Mitsu Eclipse/ Eagle Talon turbos, which had hydraulically-actuated gearshift. Many yrs ago I owned a '99 AWD turbo Eclipse GSX- a story of fleeting joy & constant tragedy mechanically, financially. Just Google "crankwalk". Yeah. ) So anyway, that's 2 transmissions I've had in my coupe with the same crunchy 5th gear... I get my car back Monday with the new (used) 6MT, and I'm wondering if that issue is just a common fail in these units OR... God forbid, there is something else wrong up near the lever/ "plunger" link assembly... But then is that even possible with a tranny swap here? Because every pic I see of a G35/ 350Z manual 6 tranny has the ENTIRE gearbox, "linkage"-whatever, and even the shift lever included as one big unit. I mean, if everything all the way to the lever is getting swapped? I've been without my precious car for 2 weeks now. Sorry for the long-winded post, any advice or info will be much appreciated, especially if it's filled with superfluous detailed tech knowledge. Thanks in advance!
-Andy Bones

 

There were 10 different 6MT transmissions used in the G35, CD000 through CD009. Through those production cycles there were 3 major revisions to the number of synchro's per gear. CD009 has the most and is generally regarded as the BEST 6MT to use, they are all completely interchangeable as a unit. They are visually identifiable by generation by the shift bracket I believe.

Don't **** with the clutch pedal play, set the clevis pin to mounting flange distance at 110mm as directed in the service manual.

Did you have them install a new clutch master cylinder and operating cylinder as well as a full fluid swap? If not I would DEFINITELY have them do it. Typically you replace ALL components when replacing a clutch.

Yep I know all about crank walk, buddy lost a motor in a GS-turbo to it.

 

>[quote]>There were 10 different 6MT transmissions used in the G35, CD000 through CD009. Through those production cycles there were 3 major revisions to the number of synchro's per gear. CD009 has the most and is generally regarded as the BEST 6MT to use, they are all completely interchangeable as a unit. They are visually identifiable by generation by the shift bracket I believe.

Don't **** with the clutch pedal play, set the clevis pin to mounting flange distance at 110mm as directed in the service manual.

Did you have them install a new clutch master cylinder and operating cylinder as well as a full fluid swap? If not I would DEFINITELY have them do it. Typically you replace ALL components when replacing a clutch.

Yep I know all about crank walk, buddy lost a motor in a GS-turbo to it.

First off, thank you for the detailed info! Since the used (though-1yr warranteed) unit has already arrived & is probably halfway done being installed I can only hope it's one of the more refined model transmissions, a CD009. I will check. Both the master/ slave cylinders were replaced about a year ago (approx. 7,000 miles, I don't drive far) and they're replacing the fluids along with this new clutch so, fingers crossed. And my mechanic has now reset the clutch point back to factory spec. My G35 coupe is a 2006 sport model, post-facelift with surely ONE of the later original 6MT tranny's, and my car has a well-maintained 128k miles on it so that particular revision either had major faults or I got unlucky. Weird that the first gearbox they threw in last week had the same crunchy 5th gear...

 

Mine is a nearly identical 2006 6MT with a full service history and 123k miles and I have worn synchros going into 3rd gear. I was planning just buying a NEW transmission sometime this summer since it's only $1800 for a new CD009.

​​​​​​Mine only shows signs of wear for the first mile or so until the fluid warms up. Hopefully bleeding the CMC/CSC fixes your issue, I'm highly suspect about you getting 2 transmissions in a row that both exhibit the exact same signs of wear...

 

Also, just because it's a CD009 doesn't mean it won't wear out over time like mine (and your original) did. That's just expected wear and tear on the part. If you're very soft on your shifts you might delay the wear to 180k but the car is a sports coupe and banging gears for 100k miles just wears the tranny out. Nothing abnormal, rebuild/replace and keep driving

 

snapped clutch pivot bolt


smoked clutch and flywheel.. it was time for an upgrade.


CD000 to 2005 model (CD005?)


stage 3 dual friction clutch and 17# flywheel


works great but I HATE the clutch pedal throw.

*stands up and holds up lighter* My name is Jeff and
I have a 2003 6MT Sport coupe and my first CD000 trans had a crunchy 5th gear. Then when I broke a clutch pivot ball I I decided to install a CD005 from a 2005 car and had difficulty shifting into 5th and 6th. Then I adjusted the shifter block plate and now its like butter.


Sounds like you got 2 bad ones (first and second one) Third times the charm..


"crankwalk hater too".. built 2.4l GST rip

 

So the vehicle has been subject to abusive driving?

So you took the vehicle to perhaps a unqualified mechanic and paid perhaps 50% of the vehicle value?

On my previous 06 G35 6 speed I still had the original clutch when I traded it in for my present 2012 G37S at 171796 miles. Never had any transmission problems except for a replaced CSC under warranty.

A manual transmission if properly driven should last well beyond 200k miles with the OEM clutch


Telcoman

 

Where's the fun in driving properly.

 

Kind of reminds me of those having fun while driving on a frozen lake.
Suddenly the vehicle cracks the ice and falls thru and sinks to the bottom of the lake.
What fun!

Telcoman

 

Cleric670- So today they got the new unit all done- a CD009, and ANOTHER (albeit very slightly) rough 5th gear! The shop owner owns a 370Z, and has owned 350Z and a G35 coupe, all 6MT & says 5th gear in these manual gearboxes, throughout the 000-009 run is a plague of sorts but fortunately, at no charge, he's opening this unit up tomorrow & rebuilding the 5's synchromesh, basically he's not letting it go until it's perfect. I appreciate your tip about the different generation 6MT boxes though, turns out he only orders CD009's but I'm glad I know this for future reference & already understand a lot more about the drivetrain in the G coupes.

EPiK- Haha, I think all ex-DSM drivers have crankwalk PTSD. Nice copper BBK calipers. Wilwood? I have the copper Wilwood 4-piston Ultralites

Telcoman-

>quote>So the vehicle has been subject to abusive driving?

Well, I've only driven manual since I was 16, I'm now 39, I maintain my car like a grown-up and I don't race or drive like an idiot so no. This isn't exactly my first trip to the rodeo.

>quote>So you took the vehicle to perhaps a unqualified mechanic and paid perhaps 50% of the vehicle value?

I take my G35 coupe to Metro Transmission, highest-rated transmission specialist in town. The price included (confirmed today, a CD009) transmission, full clutch/ fluid replacement, resurfacing of the dual-mass flywheel and now he's going to rebuild the 5th gear synchromesh in this latest unit at no extra cost. Oh, and this car is worth a teeny bit more than $5200 by the way. I can tell you're a real guru-type who knows better than anyone else, so please- think about what I should have done instead, and keep it a secret till someone asks you. I kind of understood your style internet behavior when I was a teen. Now it kinda makes me cringe. A newer user like myself respectfully asks an honest question, and generally most people are helpful & courteous, but then like clockwork someone's repellent, pompous nature rears it's ugly head with condescending & decidedly un-helpful replies trying to be the keyboard alpha boy. This isn't a politics forum or some sci-fi fanboy site. I just had a few tech questions- again, I never claimed to be an expert- and I was polite, respectful. I don't need attitude-laced quips from the world's savviest sedan driver. And BTW I'm pretty sure no one believes you average 26-27mpg in a G37 4 door, unless you live in a city designed by M.C. Escher in which you're always going downhill as part of some clever assault on physics. Your whole reply to my tech query was just snitty assumptions, all incorrect by the way, about my situation but I'm going to make a very sober one about the info proudly featured in your signature... You are in fact using 87 octane, and getting 26-27mpg, no problem, because what you drive is a G25 sedan, not a G37. If I'm wrong, I am terribly sorry. Post up a bunch of g37 pics to prove your claim, scan your pink slip, go to town. Or just forget it like I'm about to. Peace.

 

AndyBones

My apologies!
My initial reaction to your initial post was that you were some young inexperienced kid learning how to drive a manual shift and blowing thru multiple clutches and transmissions.
My previous Infinit was an 06 G35 6 speed and when I traded it in for my present 2012 G37S it has 171796 miles with the original clutch and never experienced any transmission problems
I had no idea that there were synchro problems in some transmissions so thank you for the enlightenment. Although I've been driving manual transmissions since I was a young kid more than 50 years ago it is always nice to learn something new so I thank you for that.

As far as my choice of gasoline I've never used premium except for one month tests of 91 and 93 when I first purchased my 06 G35 carefully monitoring my MPG on my 2k mile/month commute. The MPG was improved using regular 87 octane and my G37S has never seen anything other than regular.



On road trips from NJ to Florida a few times per year I get excellent MPG using regular

Four fill-ups down, two fill-ups while in Florida local driving and four fill-ups on the return to NJ



Plugs on my 06 G35 at 106.7k miles on regular 87 octane



Telcoman

 

Awesome, glad the transmission guy is going to make things right for you, sounds like he's earned his reputation.