Do we know if the 06-07 X models are affected?
Or do the Xs use different trannys? (i'd think so)

 

The TSB only mentions RWD sedans, and I've never heard from anyone with an X who had the problem (get a few PMs regarding this topic from time to time).

But I do have a general update...when I still had my G35, I took it to the dealership, showed them the TSB, let the shop foreman drive my car, and they agreed to replace the VB (even he noticed the shaking at 40 MPH was ridiculous). And my car was supercharged! But they couldn't ignore the fact that the symptoms perfectly fit the bill.

So here's the bad news, the new unit (and it was definitely new, had it verified by my performance shop) only got rid of the problem for 2-3 weeks. After that, the car started jolting at 40 MPH again when I let off the gas. My conclusion was that they replaced a defective unit with another brand new defective unit.

So I went with my plan B. The problem never seemed to surface during the first 10-15 minutes of driving after a cold start. The only correlation we could think of is that high line pressure may get rid of the problem (after a cold start the line pressure of the trans fluid is raised until it warms up). So I had my shop install a transgo shift kit (aka VB upgrade) - partially to see if it got rid of the problem (because it includes higher line pressure) and also because I was pushing dangerous torque levels. Here's where it gets even weirder, the VB upgrade softened the jolts a little (~30%), but they were still there. Me and my mechanic were completely baffled.

The only logical conclusion we could make is that this problem involves more than the VB, most likely the VB AND the torque converter.

 

Thanks a lot for your reply!
WOW, what a bummer!!!

Have you gone back to the dealer yet?

 

No need to, the G is gone. I have an 08 corvette now (manual).

 

lol, it's someone else's problem now

GOOD LUCK
I'm also look at alternatives to the G35x.

 

I had the same issue with my old engine that I had with my ATI Procharger...slippage in the transmission....I have purchased the SGP Valvebody upgrade and put that in....I love it now. 2004 model coupe.

 

I have a G35X - 2007, with 13K on the clock. Just read the TSB, I would sy that I do detect a shutter at about 40 mph going over bumps. I also complained about hard 3rd gear shifts at the dealer months ago. That seems to be better since application of a ECU upgrade, but there is still some hARD SHIFTS into 3rd gear when used in manual mode. As for the Vb problem, I had the same problem with my 3.5SL 2005 Altima. After months of complaints, they replaced the VB; that didn't work !!!. My mechanic alwyas lamented that it was the torque converter that should have been replaced as well as the VB. Sounds like the same thing is occurring here. Note that the Altima was a Front wheel drive transverse tranny. Don't know if that has any bearing (excuse the PUN) to the G35. I'm going to pay more attention to the 40 mph 5th gear shift (as per the TSB), even though I have a X model.

 

Uh oh, this is starting to look pretty widespread now. May be worth a shot to harass the dealership, even though your car isn't listed in the TSB, gonna be hard for them to ignore the fact that it has the exact same symptoms. You have to weigh the potential benefits against the risks though (getting another unit installed that *may* actually be worse). Mine was so bad it could throw a midget out the window, if you haven't gotten that bad yet, may not be worth the risk.

I wouldn't worry too much about the hard shifts into 3rd. From what I can gather, that's just normal operation of the 5AT. When I was researching VB upgrades (mostly on my350z), people always mentioned a harsher shift to 3rd after the upgrade (and hinted that it was harsh originally, but worse after the upgrade).

 

Thanks for the response. after reading these posts, I took my Black beauty for "spin". Wasn't as bad as originally thought....about the TSB. The 3rd gear harsh shift is there worse under different circumstances. I don't think I will touch anything at this time. Man, I love this car. Best car for the $$$ I ever had - at 56 years old, I've had a few...

 

To anyone who can help me out...

I found this thread a month or so ago and I had already experienced the violent shaking at about 40 mph so i took it to the dealer with a printout of the tsb listed on page 1 and they said it didn't exist and that they couldn't find any record of it. And of course I couldn't duplicate the shudder b/c it mainly happens when I am going up hill. Unfortunately, I have to drive through a tunnel everyday which goes down and up so i feel it everyday.

Open to any suggestions about what I can do?

Just some info: I have a 2006 coupe 5AT w/ every option and NAV

Thanks for any information you guys can give me!

 

Try a different dealer, or if they're the only one close by, go back and be very assertive. What are they implying when they say that it doesn't exist? That you forged an Infiniti corporate document because you're trying to get a free valve body? They're just trying to weasel out of warranty work. They have no record of it at their local site, so they dismissed it without even looking into it. You're gonna have to go back, demand that they look it up (beyond their own local records), say that you personally know people who have had it taken of at dealerships in other states. And then you'll most likely have to take a tech for a ride in your car, try to go to the spots where the problem pops up (could be a 20-30 minute drive, maybe worse). Once they actually look up the TSB, and then physically see the car shaking, they'll have to replace it. You basically have to force them into that position though.

 

Careful dealers are independent business and they can tell you to go away forever. They are not obligated to take customers just that they have a reimbursement contract from Nissan to do work which Nissan agrees to have done and Nissan will pay to accomplish.

Too many confuse a Nissan Factory Warrranty with a Nissan Dealer.

 

That may be true, but the customer also reserves the right to never buy a car or service from that dealership for the rest of their life. I'd be willing to bet that most successful dealerships understand that fronting a little cash for warranty work pays off in the long run, because most people (non-DIY'ers) would take their car back to them for everything under the sun.

In my case, I was so impressed with my dealership (for replacing my VB even though I was FI), I would have glady taken my car back to them for even the most mundane tasks (like oil), since I knew they cared about me and my car. My service manager even called me a couple months after the install to make sure the ride was smooth.

 

just want to add its with the 05 AT's also mine was just replaced cause i was getting a loud ticking while stopped in the manumatic mode.

 

I'm on my 3rd valve body, all replaced under warranty. But the shudder always seems to come back. This replacement is just a temporary fix, it is not permanent. It has been the biggest and only annoyance of my car.