Transmission

[soccer1]

Was out running around last Saturday, pulled up to a stop light, waiting for light to change felt the truck suddenly lurch like someone bumped into me from the rear. Looked in the mirror, the guy behind me was 10 feet back. Wife says, oh, I have felt that before, what is it? I said it's the transmission, and why didn't you tell me sooner?
I have since felt this a couple more times. Anyone experience this? Is what does dealer do to solve it?

 

[Zed 71]

I remember someone else on this forum having this issue, so search the fourm. Definitely take it into the dealer to have it looked at, and let us know what they find out. Hope everything works out.

 

[johnebgoode]

Sometimes it can be as simple as reprogramming the TCM. Dealer can do this with the Tech II

 

[ugachs24]

Mine used to do this and it would bang really hard when I left off the brake at a light. There was a software update out for the transmission and I haven't felt it since I had it updated.

 

[Mad Dawg]

Was out running around last Saturday, pulled up to a stop light, waiting for light to change felt the truck suddenly lurch like someone bumped into me from the rear. Looked in the mirror, the guy behind me was 10 feet back. Wife says, oh, I have felt that before, what is it? I said it's the transmission, and why didn't you tell me sooner?
I have since felt this a couple more times. Anyone experience this? Is what does dealer do to solve it?

My wife just tonight advised me that she had experienced this exact same problem. :mad2:

Mine used to do this and it would bang really hard when I left off the brake at a light. There was a software update out for the transmission and I haven't felt it since I had it updated.

What exactly did the shop do for the fix?? Is there a TSB out for this problem??

 

[ugachs24]

My wife just tonight advised me that she had experienced this exact same problem. :mad2:



What exactly did the shop do for the fix?? Is there a TSB out for this problem??

Here's what the invoice says:

"A customer states that there is a thud or bang from the rear of the vehicle when stopped and/or when releasing brake"

Cause- Vehicle is starting off in second gear.

32095 VEHICLE STARTING OFF IN SECOND GEAR. 0.90 INSTALLED UPDATED SOFTWARE.SPS CODE 10C30.

-------------------------

The tech told me it is a fairly common problem and they just came out with the update. He also said that in many cases it comes and goes and can be pretty unpredictable, making it hard to diagnose.

 

[ugachs24]

I forgot to say what the actual problem is :ktoe: .

He took about 5 minutes explaining the issue to me but in a nutshell, he said sometimes the tranny won't ever actually downshift all the way to 1st gear when it comes to a stop. After a minute or two, or sometimes when you let your foot off the brake, the transmission will realize that it is in second gear and try and quickly correct the problem, thus resulting in the thud. He said it doesn't do any damage to the drivetrain, it can just be a shock to the driver when it occurs.

 

[Mad Dawg]

UGACHS24, much thanks for your very helpful info. I drove the Tahoe in to work this morning, mixed driving with some interstate, totaling about 17 miles. The tranny went up and down through all the gears without any problems whatsoever. For the time being, I guess I will just monitor to see if this issue develops into something worse.