G37 rough downshifts (automatic)?

[RichardnVA]

Anyone experiencing rough / abrupt downshifts with their g37 automatic? I have a g37x with about 1600 miles. Downshifts from 3rd to 2nd and 2nd to 1st are really rough and you feel the whole car lurch forward. Not smooth at all. It's done this since I got the car, and was hoping it would get better after a break in period. No improvement after 1600 miles. Any similar experiences out there? Any suggestions? Should I bring it in?

[SteveTheTech]

Welcome to Nico,

There is an Transmissions Control Module (TCM) reflash for some of the G37s with the RE7R07a transmission. This seems to resolve many of the inappropriate shift characteristics of this transmission. After you have the software updated a few hundred miles may need to be logged to reset the adaptive memory.

[Pamywyner]

Yes! In fact, I noticed it today more than usual. My son asked me what the heck I was doing. I told him 'it's downshifting weird today'. He says "oh mom, you don't know how to drive this car!"

All I was doing was lightly putting on the brakes while going down a hill and around a slight bend and it seemed to be 'revving' on its own.

My husband is fishing in NH. He's a service manager for Goodyear. I'll have him drive it when he gets home. I have an appt coming up next week at the dealer for them to listen to a clicking sound in the engine.

Only 2,000 miles!?

[SteveTheTech]

The reflash will resolve the issue you outline in some regard. As I mentioned above there may be some time needed to relearn your long term adaptives.

I spent many years working at Goodyear in high school, it was a great learning experience and those are still the only tires I ever purchase.

If you want to get your sons attention put the car into DS mode step on the throttle.

[Pamywyner]

The reflash will resolve the issue you outline in some regard. As I mentioned above there may be some time needed to relearn your long term adaptives.

I spent many years working at Goodyear in high school, it was a great learning experience and those are still the only tires I ever purchase.

If you want to get your sons attention put the car into DS mode step on the throttle.

He's 16 and going for his driver's test on Oct.13th. He WISHES he could get his hands on the G!

Thanks for the info and I'll def ask about that reflash!

[SteveTheTech]

He's 16 and going for his driver's test on Oct.13th. He WISHES he could get his hands on the G!

Thanks for the info and I'll def ask about that reflash!

I wish my parents had one of those when I was that age. However as I am getting older I know I would be singing a different tune now. A car that accelerates from a dead stop to 60 in 5.1sec ( http://www.autoguide.com/manuf....html ) should never be in the hands of an inexperienced driver. I had my license suspended in an 89 Accord when I was that age.

Keep us posted.

[G_whizz]

Welcome to NICO!

PLease follow Steve's suggestion and let us know if it was in fact resolved!

He's 16 and going for his driver's test on Oct.13th. He WISHES he could get his hands on the G!

Not a chance in hell eh?? LOL

[Pamywyner]

No chance!!! He did some 'learning' on it which made me cringe but, luckily we had to be in the car with him and he's going the speed limit still. Once he's driving on his own, we're gonna help him get into a little 4 cyl. to start with!

As far as the weird shifting goes, I am going to have this checked out next week for sure! I'll keep you posted!!! Thanks for the input!

[RichardnVA]

Do you know if the reflash is a standard procedure that is covered under warranty? Should I set up a maintence appointment with the dealer and tell them about the problem? My concern is the typical "we couldn't recreate that problem on our test drive" and nothing get's done. Do I tell them I want a reflash?

[RichardnVA]

Steve,Thanks.How do I know which transmission I have?You mention the RE7R07a, are there different automatic transmissions available for the G37x?Do the x's have a different transmission than the RWD?Before I take it in reflash the TCM, I want check and see if I have the RE7R07a.Thanks,Richard

[Pamywyner]

Mine is going in on Saturday for it's first oil change and to listen to a weird noise in the engine. My husband thinks it's part of the muffler system. ?? We are also going to mention this shifting problem.

Right now, I'm missing my '04 coupe!

[jandpharper]

Had the auto trans reporgrammed yesterday in my G37X.Knowing about the TSB and reading all the posts from ownersI was curious to see what the service manager told me.She asked me if I had any problems with the car and I toldher the transmission was "quirky"...she knew exactly whatI meant and told me they could make the downs***s alotsmoother...and that's exactly what they did. It madea considerable difference and I'm very pleased with theresults. BTW...I also told the dealer that the car wasnot holding a centerline verywell and it tended to hopin tight curves....they did a 4 wheel allignment and toldme it was very out of allignment front to rear even thoughit was not pulling hard to either side....Again, couldn'tbe happier. The allignment made a big difference insteering feel, and without knowing what happended,my wife commented, "what did they do to your car? ithas a much better ride and is smoother."

[SteveTheTech]

How do I know which transmission I have?You mention the RE7R07a, are there different automatic transmissions available for the G37x?Do the x's have a different transmission than the RWD?Before I take it in reflash the TCM, I want check and see if I have the RE7R07a.

The RE7 is standard on all automatic G37 09+. Whether the car is rwd, awd, or sport model they all share the new 7 speed. I think the only model still using the RE5 is M35x and M45 and it's x model, but that is another thread in a different forum.

Mine is going in on Saturday for it's first oil change and to listen to a weird noise in the engine. My husband thinks it's part of the muffler system. ?? We are also going to mention this shifting problem.

Right now, I'm missing my '04 coupe!

Did they end up finding the noise?Did you go with the ester oil?If the noise is at idle I know some models have a reflash for the ECM that adjust the base VVEL positioning and that has a large impact of some of the noises the engine makes. Ahh yet another reflash although this thread covers the only two software adjustments that get the most attention. The audio unit is a different unit and their software is updated frequently with no mention to us.

The 04 coupe was a great car for its simplicity and ease of use. However they kept the design pretty much the same for four years in the coupe it was desperately in need of a full makeover. I personally think the new and old model are not even in the same category.

Good luck with the updates.

[DAAN.]

is this reflash available on canadian models, as well ?

we got our x 2 months ago and the salesman does not have a clue and we're waiting for the service dept

[Pamywyner]

Got the car back today with it's first oil change and had the reflash done. Already noticed a nice change in the downshift! So far so good.

They could not find the engine noise so, my husband is going to keep an 'ear' on that. I think it bugs him more than me!

Another thing that I was happy about was there are no new scratches in the paint after being in the shop. I was worried about that after reading some horror stories. Then, I go to my salon and some little rug rats were outside throwing rocks at a dumpster near my car!!! I hollered out the window at them to stop!!! Kids! Luckily I don't have any dings from that.

[RichardnVA]

Welcome to Nico,

There is an Transmissions Control Module (TCM) reflash for some of the G37s with the RE7R07a transmission. This seems to resolve many of the inappropriate shift characteristics of this transmission. After you have the software updated a few hundred miles may need to be logged to reset the adaptive memory.

Steve, I finally brought the 37x in to get the TCM reflashed. Worked like a charm! What a difference. Thanks for the tip. One minor point for anyone who plans on bringing their car in for a reflash: I told them I would wait for the service and they said it could take up to 2 hours for the reflash to complete. I waited anyway and it only took about an hour, but just in case be prepared.Thanks again!