ike

With the shifter in drive - if you nail it from a slow rolling start in 1st gear, at what RPM does your trans shift into 2nd ?

Mine doesn't get close to redline and the 1st to 2nd shift feels lazy to me. I've seen reports that the 1st to 2nd shift was nice and crisp and caused the tires to break loose slightly. That's not my experience. What's yours ?

I've got the 2.73 gears but that shouldn't affect the shift crispness or RPM.

Lil Red Corvette

I have the same configuration as yours, but mine is a very crisp shift just before redline.

ike

Something must be wrong with mine. I've been reading a little about the torque management and that Cartek device. I don't know if this has anything to do with it but my 1st to 2nd shift is not good. It refuses to go to redline at WOT and the shift is plain lazy.

Lil Red Corvette

I sure would get it looked at! I am very pleased with mine!

Tommy D

I have the A4 with 3.15s. Make sure that you have the traction control and active handling off. Hold the button down for 5 seconds the dic will notate that both are off. You should notice a material difference in the 1-2 manual upshift

There is a TM program that retards the timing as the car approaches the redline and also as the coolant temp increases. The traction control and active handling control will reduce the power output and not let the car spin the rear tires. However, I have not experienced any bog or any loss of power manually shifting the auto with the TC and AH off.

purple heart

My friend, I personally think that the problem you have, if its not the TC & AH not in the off position, is with the gear ratio. I don't have a problem chirping the tires on my LT1 96 Z51 Auto from 1st to 2nd and it has the "performance axle ratio" gear 3:07! Now, my new C6 vert. is coming thru with the 2:73 gear but I'm in the process of finding out from 2 local chevy dealers if I can install a complete carrier that already has the 3:42 axle ration gears rather than the 3:15 gears-which is a factory option for Automatic transmission. But the point is I do believe its the rear axle ratio that will make all the difference when starting from a dead stop(and assuming the AH & TC are off too.) This might be a "bit" costly, but to me, (and thats what this is all about-what satisfies you, me, and whoever else) it's worth it. Plus, you don't lose your warrenty either!

JJayzX

You might not lose warrenty but you sure do lose rubber.

2005ArcticWhite

Crisp on the shift.
I have the 3.15
Also at times I work the gears, auto trans, 1 to 2 to 3.............

ike

I will try turning off traction control and AH. But it seems strange that this would have any affect on the shift RPM or shift crispness.

If anyone replaces their 2.73 gears with something better, I would appreciate knowing what you had to go through to get it done.

FLC6

Sorry about your problem. Let us know what they find.

tom4416

Auto w/2.73 gears and at WOT from a stop, it will hard shift just before redline (6200/6300) and chirp the tires before TC stops the tire spin. It gets lazier in the 2/3 upshift and the 3/4 which is probably a function of the gearing. Turning off TC and AH has no effect on the feel of the shift or the shift point, only teh resulting tire spin after the shift.

RWSjr

Mine is auto with 3:15's. When in comp mode and in drive, 1st will go to rev limiter about same time as it shifts. It'd be nice if it shifted a 100 rpm sooner or rev limit was 100 rpm higher.

rbl

ike

This is what I was expecting from my car. I was shocked when it shifted around 4800 and so lazily that when it hit second, the engine felt like it was lugging. WOT should make the transmission wait until near redline to shift.

Then I tried shifting manually at redline. The shift was OK but the car was no where near interested in breaking the tires loose.

I'm a little nervous about bringing this up with my dealer. A. The'll know I'm running it hard and B. they'll have to dive my car at WOT to test it.

I wonder if there are any TSB's for something like this yet ?

bj33813

May just be a transmission pressure problem or adjustment. Check it out.

DebtCraft

I get a solid shift into second from a WOT dead stop. At times, the car seems to lunge forward actually. About 1 time out of 5 I get a chirp.

Shift is right before redline.

AveryOBX

This question has no right answer. The C6 has algorythm transmission which means it "learns" how you drive. Everyones will shift differently because of this. Mine is nice and crisp, near redline. And with traction/handling off it will break the rear end loose.

jmess

With some cars you can get them to forget what they have learned by disconnecting the battery and putting your foot on the brake for a few seconds. It has been claimed on some of the sports sedan boards that this will reset engine and auto ECUs (along with some presets like radio, seat memory, clock?)

rbl

Her ya go TSB 1800your76nuts.

I am more nervous about YOU driving it at WOT and where you are doing it at. Yea, I know your're real safe and all that stuff, right!

The car is obviously a dog and I'd just get rid of the pig.

WhiteC5Vette

Actual shift points are determined by throttle position, engine speed and torque values, engine intake air temperature, accelerator pedal position, engine coolant temperature, kick-down request, traction control status, driver selected shift mode, air-conditioning status, cruise control status. The adaptive shifting is used to regulate the speed of the shift in regard to slippage of the engagement it is not used to actually determine when the shift occurs.

It compares the actual shift time to an algorithm and if the actual shift time is greater than the calibrated shift time (such as a slow engagement) the TCM will increase line pressure for the next upshift under the same condition. This way, the shift quality stays the same throughout the life of the transmission. If it didn't then as the trans got older, and there was increased wear on the clutches, the trans shifting would get sloppy over a period of time.

Not sure if on this TCM, disconnecting the battery will reset the transmission adaptive program values. It could be using a non-volatile memory chip and resetting with a scan tool may be the only way to reset the values.

Wide open throttle shift should occur at:
1-2 shift: 2.73 axle 44 mph; 3.15 axle at 38 mph
2-3 shift: 2.73 axle 87 mph; 3.15 axle 75 mph