I called the Service Department at SouthWest Infiniti in Houston, TX. I asked him about this and he knew what I was talking about. He said he'd run all the updates when I bring my car in next month for its first scheduled service.

 

Yes, include on Custom Report
SERVICE BULLETIN:ITB07-048 NHTSA ITEM NUMBER:10024351

MFG Bulletin Date: 20080221

Component: ENGINE AND ENGINE COOLING:ENGINE

Bulletin Summary: 2008 G37; INTERMITTENT/SHORT DURATION SMALL RPM INCREASE DURING BRAKING, WITH AUTOMATIC TRANSMISSION ONLY BUILT BEFORE DEC. 6, 2007. VIN - BUILT BEFORE JNKCV64E(*)8M 115669. *NJ

Date added to datbase: 20080408

 

Correct me if I'm wrong but this doesn't apply to the OP or the people exeriencing the downshift problem on g37 SEDANS. the TSb info you've given does not appear to apply to any 09 g37 sedans.

 

I believe the 08 transmission referenced in the TSB was carried over to the
09 g37 sedans. A 2009 TSB will update the issue.

 

Well dealership is all about taking care of this. My salesman who drives the same car said he noticed it. They are looking into the update and expect to have something to me by next week or ealier. My loaner was great but it had the same problem. It seems I helped them a bit and they appreciate it. Not great news for me but I can wait as long as they don't bs me.
Impressive service so far. Don't expect a problem

My windshield was replaced. The car was returned spotless inside and out.

Kicker was seeing my Maxima on their lot all perfect again. Salesman said that he has a buyer now. Cool stuff IMO.

 

I spoke to my dealer. They said there is currently no update available, but heard that one may be coming out soon. They had contacted the dealer in Denver. They were told by that dealer that the program that was installed on their customer's car was done by their Technical Service Manager but was not readily available to the dealer network as of yet. My dealer put my name on a list of people to call when the program change becomes available.

 

THis transmission definately has a good side. I hope this makes you guys feel a little better!

http://www.caranddriver.com/reviews/...take_road_test

Holy **** thats FAAASSTT!!!

 

HOLY ****TT is right. 108mph in the trap speed. Guess thats what happens when you lop 400lbs of weight off the G.

BTW: Motorweek was able to rip off a 0-60 of 5.2 and 1/4 of 13.7@103mph! with a 37X Coupe 7AT. Thats car is the heaviest of the G-Lineup..heaviver than the G Sedan AWD. Assuming the performance isn't much different, I can live with 0-60 times in the low 5's!

 

I read that Motorweek review (or rather saw video http://www.youtube.com/watch?v=Pz--pDazysk) but they also got 6.0 seconds for an 08 RWD G37 coupe 0-60 so I really question their accuracy. The most accurate in my opinion is the Motor trend article www.motortrend.com/roadtests/sedans/112_0904_2009_infiniti_g37x_s_sedan_test/index.html
that says 5.4 and 13.9 for the Xs. Thats definately fast enough IMHO. The way the car feels is much more important to me though, i would be happy to give up 30-40 horsepower for 30-40lbs of torque even if the 0-60 time slowed down a bit (but it wouldn't) LOL...

I finally got a decent (still not great) quote from a dealer over an hour away from me, so I am going tomorrow to test drive an Xs. If I like how it drives(anything like the RWD sedan and coupe), I might be coming home in one.

 

I just got back from the dealer for my first oil change and I asked them about the new update and he told me there is no new update

 

I noticed the downshift when I was test driving the car. It did not really bother me then or now. I am used to downshifting to slow when I drive a stick, and using engine braking at slower speeds. It was a little suprising to have the car slow as quickly as it does, but noting the differences in the gear ratios it is not unrealistic to expect. The key here I think is that this is not your typical soccer mom sedan. It is geared towards drivers, and as such will downshift in expectancy of either continuing to slow, or to resume speed. This means there will be no wait or fumble as the throttle is reapplied and the transmission has to adopt a new gear.
My truck provides much the same attitude when I use tow / haul mode, so this is a little similar in action.
There may be some cars which are overly harsh in the way they downshift, but mine is not to me. I do seem to be experiencing a transmission learning curve at the moment, where under very light throttle the car seems to lurch a bit in the gear changes, but I find that preferrable to vague slush box behavior. That is why I don't like Nissan's CVT.
Of course I don't have 600 miles on the car yet, so we will see what things are like when it has 25K on it.

One note>
It might take other drivers by suprise who are following you, if you coast down to a crawl.
But when I was driving a 6sp stick they got the same situation quite often. You can just about come to a complete stop in some instances without ever touching the brake pedal.
So it never hurts to be aware of drivers behind you as well as in front...
Light pressure on the brakes to make sure the lights let them know what is going on, because you can never be sure if they are on the phone or asleep.

 

dbg...

The problem is that the car downshifts irregularly sometimes causing a big jerk in the car to where it is really bad. Sometimes it does it... Sometimes it doesn't... Then if you have to accelerate normally after braking from 27 to 20 the car will stumble making it into 3rd. It's almost like the car just doesn't know what to do...

If I was driving stick I would downshift when I want to and at my speed and then there's the clutch. All of my passengers are surprised when they ride and notice it.. My passengers have asked me if its normal. I say it is normal in this car. Yes I know how to modulate braking and expect the engine braking but the problem is it's intermittent but happens often enough to get recognized.

 

Sounds like not every car is showing the symptoms. Mine has never caused a jerk or stumble that I can think of. Just a noticeable pull down of speed when it shifts down.
Makes me wonder if it is just particular models or before a certain build date. Mine is just the standard RWD journey, not an S, X, Xs etc.
I also wonder if it is related to the ECU learning the throttle map and the tranny not knowing if the car is under deceleration or under a feathered throttle.
I noticed that driving a certified car for a test drive before buying my new one that there was a very touchy throttle in the 08 car. It was very hard to take off smoothly with a light touch. Seemed like it wanted to launch at a good rate all the time.
That might be fun, but it doesn't do much for mileage.
That 08 was a corporate lease car, so I doubt that the driver was paying for the gas.
I know that every driver is different, but I tend to notice that an awful lot of people tend to stomp on the throttle and then ease up as opposed to gradual pressure.

That is why even middle aged soccer moms in mini vans tend to pull away from lights faster than I do, they treat the accelerator pedal like an on / off switch.
That is probably the reason why they have the ECU learn the driver, but also why drive by wire is way too complicated for its own good.

 

Has anyone heard anything more on this? I'm at 1500 miles now and its better but still there and out of the ordinary.

 

Every once in a while i'll be coasting with foot off the pedal (say, at about 20 mph) and i'll jump on the throttle and feel like i caught the gears changing and it'll clunk (felt, not heard) a little, but this is once in a blue moon .. and every once in a while i'll feel a subtle down shift as I brake to a stop .. nothing major and definitely nothing that bugs me.

Mercedes owners with 7AT's experience same things... you should read some of the 7AT horror stories from MB owners... google "Mercedes Benz 7AT problems"