UPREV also confirmed that they are looking into at least reading from the TCM using CIPHER. Not sure they are really considering "upgrade" possibility (like a ECM reflash, which apparently is in the works), but they have said that if they create that it would be a separate product (not CIPHER).

 

I really wish I would have seen this thread a few months ago!!

I posted an annoyance I have with my 06 G35X auto-shifting logic here:

https://g35driver.com/forums/g35-sedan-v35-2003-06/83130-06-g35x-auto-shift-question.html

As you can see, I am having some issues coaxing it to shift when I want. After reading this awsome thread I hope some of the posters to it are still tracking. Will resetting my ECU help? Will other mods help get it to do what I want? The one post that talked about the converter (may not be the exact right term) "spin-down" timing and being able to adjust it is what I am experiencing. Any help most appreciated....

BJBBJB

 

Well I guess this is a conversation wtih myself but in case this helps someone...

My dealer told me they were 100% certain that you could not reset the 06 G35X so the automatic could re-learn. When he learned I knew what re-setting the ECU meant he agreed that could be done, but again he said that would not allow the automatic to re-learn it's shift patterns.

Hopefully one of our Infinity mechanic gurus can confirm this....it does seem to run contrary to what I have read on the boards.

BJBBJB

 

I'll second the interest in this...

 

Actually...

more so even than the quicker upsifting... I wish there was a way to get the tranny to coast.

To Let the RPM's drop completely down to an idle, when I'll cruising down the freeway...

We, the wife and I, would love to have more performance out of this car, but we do realize that it really is our daily driver.... and if there was a way to get it to coast when we're off the gas and in auto mode... I'm sure it would sure help on the gas mileage.
Currently at 65 mph if i let off the gas pedal completely going down a long hill, the car only drops a few 100 R's... too about 2500 I believe.

Well if the car is burning 12.7 : 1 at 2500 rpm's... that's alot more fuel than 12.7 : 1 at 1000 rpms.... unless I'm totally wacked in the head, that's 2.5 times the amount of fuel that is really needed to go through my engine while coasting.

And considering I live in Colorado and it's all hills and mountians where I live, I'm coasting about half the time I'm driving... so if half of the time I'm driving, I could save 2.5 times the fuel.... that would be a hell of a savings.

Too me it looks like a win-win situation.

We used to have a Pontiac GTP that was great at coasting, it had a 285 HP Supercharged 3.8 L motor, and would always get 30 ish mpg. the only huge difference I can see between the G and it, is this Coasting thing.

Another thing is that if I want the car to hold back... going down hill... I already just put it in the Munual mode, and that works great.

My second priority would be the quicker upshifts. Currently it takes 5 - 600 R's to complete a manual upshift under full acceleration.

(04 S G35x 5AT)

 

Shifting the transmission to Neutral is an option but that simply would not be practical when driving on the freeway or highway.

 

I've tried the shifting into nuetral bit...

when I was getting low on gas and wanted to make sure I could make it to the next town, but I don't do it on a daily basis.

I was thinking about getting a higher stall converter.... but I'm not a tranny guy... so I really don't know if that would work... especially with this car.

I just don't know... what if any my possiblities really are...

so I'm all ears.... if anybody's got any good ideas.

 

EVLG35X,

Can't help you with the coasting....although I do have fond memories of Trail Ridge rides.

Faster upshifts - YES! I love this car, but I just cannot get used to how long it takes to finally shift into the next gear at times. Unless you are mashing on a 0-70MPH run, it just spins and takes forever to shift.

Don't get me wrong...I like the fact that it lets you run up the RPM's before starting to shift...but once it decides to shift, it should just SHIFT!

That's what I get for getting only my second automatic car ever... It might make me hope for an 07 manual X....

BJBBJB

 

Trail Ridge is a beautiful road, but there are others I like better for Drive and Riding on...

As for the shifting thing ... well I drove a FX the other day (Loner Car)... and couldn't believe how fast it shifted (1-200 R's) compared to my car...

it just made me stop for a second and go "were these tranny's really made by the same manufacturer ?"

Nice quick and positive upshifts... without being harsh.

My G, even after restting the ECU, takes at least 400 R's and sometimes 600 R's to shift.

And just for clearification, what I mean is when I'm in the ManualAuto mode, the amount of time it takes (R-rpm's) from when I bump the shifter.

...

 

Gord's Grounding Gear helps with the shifting on AT cars.

The torque converter already has a very high stall (2600-2900).

I concur that it would be nice to be able to coast in neutral directly from manumatic mode...

 

I had the GG wires and it made no difference in the way my 03 sedan shifts. At 80% throttle or less, the tranny shifts almost instantly when in MM. At WOT on the 1-2, it can't keep up and I'll usually hit the limiter. For the 2-3, I shift at an indicated 6400rpms and the shift is executed by 6600-6700rpms.

A high stall TC would hurt MPGs because there is a lot more slippage on initial take off.

The G35 has pretty deep gearing hence the reason for the worse MPGs. Even with the TC locked in 5th at 80mph, you're stilling spinning 2700-2900rpm depending on drivetrain RWD or X. The GM cars have wide ratio 4 speed autos. At 70mph, they typically roll at about 1500-1800rpms in 4th with the TC locked. The big displacement pushrod V6 makes excellent low rpm torque therefore the car can spin very low rpms and be fine with it. However, when it comes time to pass, a shift into 3rd or even 2nd is required. Just to give you an idea of wide ratio of the GM 4-speed autos, the Pontiac GTP 4AT can do about 92mph in 2nd gear. No joke. Since the GTP has a torque rich SC 3.8, it doesn't need all the torque multiplication from gearing. My G 5AT on the other hand does about 64mph in 2nd and does 101mph in 3rd. The G needs the torque multiplication to make up for the lack of torque. The G makes about 215wtq stock whereas the GTP makes about 270wtq stock.

Honestly though, I wouldn't trade the deep gearing for taller gearing because the stock gearing is ideal and rarely do you feel like you're in the wrong gear. At highway speeds, there's no need to downshift because 5th can usually pull enough for most passing manuvers. On highway trips I see 26-27 mpgs and I see 18-19mpg in 100% city driving. I'm not complaining.

 

And if you get the M35 you get even faster ratios as I understand it from snooping over in thier area. That ratio change gives the heavier car equal acceleration in passing situations they say.

 

Well that all makes sence...

Thanks.

 

DaveB, I think you got a tranny that is better than most in stock form. Mine did not shift instantly in MM mode - ever - till I put the GG on (2004.5 5AT coupe).

I think 5th gear should have been taller - to allow cruising at 2000 rpm around 75 mph. I actually wonder if they were locked into the shorter gear ratio because the TC has such a high stall of 2600-2900 (per my service manual). I know it has a "locking" feature, but maybe it needs to be near the stall rpm????

 

RCDash,

I also have the service manual. I have looked, but I cannot find where it shows definitively how to reset the ECU and then the shift learning so I can....well, gently point my dealer to it.

I see on the forum a few ways to do it yourself, and I may end up doing that. But I was hoping I could just find it in the manual

BJBBJB