2003 Trans. Clunking

[silvered]

HELLO, IM NEW TO THIS. I JUST BOUGHT A USED 2003 CHEVY SILVERADO EXT. CAB SHORT BED Z71, WITH THE LS TRIM. IT HAD ABOUT 11,000 MILES ON IT WHEN I BOUGT IT A MONTH AGO. WELL FIRST I NOTICED THE TRANSMISSION CLUNKING BETWEEN 2 AND1 GEAR ON A DOWN SHIFT UPHILL. NOW I NOTICE A STUTTER BETWEEN 1 AND 2 GEAR WHEN I TAKE OFF. IT IS NOT ALL THE TIME. ALSO WHEN I HAVE MY CRUISE CONTROL ON. ON THE HIGHWAY, IT LIKES TO JUMP BACK AND FORTH GOING DOWN HILL. BUT WHEN I TAKE IT OUT OF CRUISE AND JUST HOLD STEADY AT SPEED, IT IS FINE. IF ANYONE HAS ANY INFO ON ANY OF THESE TOPICS PLEASE LET ME KNOW.

[nakedavalanche]

I have a 03 avalanche and I have similiar problems. I took it to the Dealer and I have no problems. I taled to a performance shop and they let mu use a Hypertech power programer for a week. Wow what a difference. It really smothed up the transmision.

Supposibly the reason people are haveing problems today is GM found that they get better life out of a transmission if it shifts down, istead of locking up the tourqe converter witch causing heat.

I have been in a few trucks and mine is "was" the worst.

With Hypertech it is like my 98' used to be.......................

Good luck

[jpindorski]

Learn to live with it or take a loss and buy the new 2004 Ford. You've bought a "Clunker."

I just today took my new 2003 "Clunkrolet" Silverado with 7000 miles on it in to the dealer for the second time for the infamous clunking problem. The first time they used some type of "magical special grease" which lasted about a week before the clunking returned. They told me it was the slip yoke banging and it was a normal noise. The standard response is it's "operating to the manufacturers specs, they all do that and it's normal." Normal my a$$. Fords and Dodges don't go clunking around the roads like my Silverado does. The dealer told me that's because they are designed differently. It's an obvious engineering problem. I read where one fix was a nickel plated slip yoke and I mentioned that to the service guy today and he said the 03's already had those on them. Well, then that wasn't a fix was it? I also read where they were replacing the drive shafts. Anyway, one way or another, I want the problem resolved. They told me they can't fix it because it's normal. I might look into the lemon law. That might be a start. Or maybe a complaint with the Feds. I know for sure I will be calling GM's complaint line.
We have been a GM family for 30 plus years. My wife drives a 2003 Buick and I've always been loyal to GM. But I swear that after paying $32,000 for a vehicle with such a glaring problem and getting an "it's normal" excuse from GM I will sell the "clunker" and go with the 2004 Ford truck ad you won't see another GM car in my driveway.
My advise to someone thinking about a Chevy/GMC truck is to think again.


Here's GM's Service Bulletin:

Driveline - Clunk Explanation
File In Section: 04 - Driveline Axle
Bulletin No.: 99-04-20-002A
Date: September, 2001
INFORMATION
Subject:
Driveline Clunk
Models:
2002 and Prior Light Duty Truck Models
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number 99-04-20-002 (Section 04 - Driveline/Axle).
Important: The condition described in this bulletin should not be confused with Driveline Stop Clunk, described in Corporate Bulletin Number 964101R (Chevrolet 92-265-7A, GMC Truck 91-4A-77, Oldsmobile 47-71-20A, GM of Canada 93-4A-100) or Bump/Clunk Upon Acceleration, described in Corporate Bulletin Number 99-04-21-004.
Some owners of light duty trucks equipped with automatic transmissions may comment that the vehicle exhibits a clunk noise when shifting between Park and Drive, Park and Reverse, or Drive and Reverse. Similarly, owners of vehicles equipped with automatic or manual transmissions may comment that the vehicle exhibits a clunk noise while driving when the accelerator is quickly depressed and then released.
Whenever there are two or more gears interacting with one another, there must be a certain amount of clearance between those gears in order for the gears to operate properly. This clearance or freeplay (also known as lash) can translate into a clunk noise whenever the gear is loaded and unloaded quickly, or whenever the direction of rotation is reversed. The more gears you have in a system, the more freeplay the total system will have.
The clunk noise that owners sometimes hear may be the result of a buildup of freeplay (lash) between the components in the driveline.
For example, the potential for a driveline clunk would be greater in a 4-wheel drive or all-wheel drive vehicle than a 2-wheel drive vehicle. This is because in addition to the freeplay from the rear axle gears, the universal joints, and the transmission (common to both vehicles), the 4-wheel drive transfer case gears (and their associated clearances) add additional freeplay to the driveline.
In service, dealers are discouraged from attempting to repair driveline clunk conditions for the following reasons:
Comments of driveline clunk are almost never the result of one individual component with excessive lash, but rather the result of the added affect of freeplay (or lash) present in all of the driveline components.
Because all of the components in the driveline have a certain amount of lash by design, changing driveline components may not result in a satisfactory lash reduction.
While some owners may find the clunk noise objectionable, this will not adversely affect durability or performance.

[ryder379]

I have the same problem here. I just went through my first round at the dealership. They gave me the same run around as noted above. Have any of you gotten anyware since the last reply?

According to the service bulletin this is due to backlash in the drive train. I am not an expert on automatic transmissions, but to me it feels more like the transmission is shifting when the gears are not at a matched RPM, causing a horrific “clunk”.

As far as the cruise control, mine does the same thing. More annoying than anything else. I just tap the brake and use the throttle until I get to the bottom of the hill. I had a 93 chev pickup and didn't have this issue. Very disappointing to see we have step backwards in technology.
.

[jpindorski]

Well, Ryder, I don't know what we can do. I just got back from a short 350 mile trip and the clunking problem is becoming real loud and frequent. The truck actually shudders. And I'm really ticked off at GM. I was told by a friend who works for Chrysler's to ask to speak to a zone manager and then to his boss and up the ladder until I got some satisfaction. Well, I called the dealer yesterday and talked to a service advisor and asked him about how I go about speaking to a "zone manager" and he said they don't speak to the public. I then asked to speak to the service manager and he told me he was in a meeting and that he's call back. I'm still waiting......hmmmmmmm.

I called the GM complaint number and filed a complaint with them. I asked the person on the phone what happens next and she said "nothing". "We have it on file." I plan on filing a complaint with the Better Business Bureau's BBB Auto Line. (800) 955-5100 or online at www.dr.bbb.org/goauto. It probably won't help but I'm not laying down for GM or anybody else that sells me a defective product.

I also am going to write a letter to the President of GM and send a copy to my newspapers automotive section. I don't believe there's a fix for this problem because of GM's shoddy manufacturing or design of the gears that are causing the gear lash and they know it. They've sold thousands of these defective trucks and are now trying to cover their butts.

GM used to have a jingle on that went something like this:
"See the USA in your <Chevrolet> CLUNKROLET"

[Dakotarota]

Dropped mine at the gmc delaer yesterday for the same thing. Sold me some $30 lube & we'll see what happens with it.

[jpindorski]

Hope it works Dakota. They used the special magical lube/grease on my mine the first time I took it in saying the slip yoke needed greased and was causing the clunking. It didn't work.

BTW, I just talked to the service manager and he told me that they were just a repair facility and had to go by what GM says and GM says there's nothing wrong with my Clunkrolet. He told me he'd drive my truck for a day and if the clunking was no different from any five other new trucks off the lot there would be nothing he could do. Sure he'll drive it because he knows they all clunk. He told me I couldn't talk to the zone manager and to call up the GM complaint line again and make another complaint. I've read on another site where GM is extended the warranties on the transmissions to 100,000 miles if you complain loud enough and contact the BBB Autoline. The service manager denied any knowledge of this. I'll calling the BBB right now.

"See The USA In Your Clunkrolet'

[gmt560]

Took mine in with only 200 miles on it with same issue. They had a TSB out there to reprogram the Trans Control Module with new cals. It significantly reduced the clunks and slips but did not eliminate them. I think there's too much pep with this 5.3 to get a smooth shift.

Also, had my VIN fallen within a certain range the Service Manager said it would have needed some mechanical work that was specified on the TSB in addition to the reprogramming. Good Luck.

[jpindorski]

Thanks for the info GMT. I'll call the dealer tommorow and ask him about reprograming the trans module. Would you happen to know the bulletin number for that service?

Also I talked to a lawyer today and he stated I'd have to take the truck into the dealer's 2 more times for a total of 4 and then he would take my case under our state's lemon law.

[Dakotarota]

ANd they had toprogram the ecm for a new shifting program & cost me 100.00 Woulndt that be covered somewhere if the last one was bad??

[GMMerlin]

I did a bulletin search this morning and found a couple bulletins that MAY apply to the concern on your truck.
My recommendation is to take it back to the dealer and talk to the service manager and ask him to perform a bulletin search on your specific concern while you are standing there with him.
There are 2 bulletins for a 1-2 shudder on those trucks.
I had the 1-2 shudder on my 02 Sierra and I fixed it per the bulletin...Smooth as silk now
If you need more info feel free to PM me.

[beaks]

I have a '01 z71 ext cab with 30,000 miles on it. I just bought it used and I have the clunk in th rear end from park to reverse. Had it in for warantee and of course the same old answer "its normal". I like your info and the service bulletin you posted. Hopefully it is true that no damage or reliability issues will occur. My mechanic said too much play in the rear end so I took it to the dealer. Oh well, I may have my machanic take it apart to see what he thinks. I would rather pay him to fix it than go through the hassel and grief with the dealerships.

Cheers.

[beaks]

Originally Posted by jpindorski

Learn to live with it or take a loss and buy the new 2004 Ford. You've bought a "Clunker."

I just today took my new 2003 "Clunkrolet" Silverado with 7000 miles on it in to the dealer for the second time for the infamous clunking problem. The first time they used some type of "magical special grease" which lasted about a week before the clunking returned. They told me it was the slip yoke banging and it was a normal noise. The standard response is it's "operating to the manufacturers specs, they all do that and it's normal." Normal my a$$. Fords and Dodges don't go clunking around the roads like my Silverado does. The dealer told me that's because they are designed differently. It's an obvious engineering problem. I read where one fix was a nickel plated slip yoke and I mentioned that to the service guy today and he said the 03's already had those on them. Well, then that wasn't a fix was it? I also read where they were replacing the drive shafts. Anyway, one way or another, I want the problem resolved. They told me they can't fix it because it's normal. I might look into the lemon law. That might be a start. Or maybe a complaint with the Feds. I know for sure I will be calling GM's complaint line.
We have been a GM family for 30 plus years. My wife drives a 2003 Buick and I've always been loyal to GM. But I swear that after paying $32,000 for a vehicle with such a glaring problem and getting an "it's normal" excuse from GM I will sell the "clunker" and go with the 2004 Ford truck ad you won't see another GM car in my driveway.
My advise to someone thinking about a Chevy/GMC truck is to think again.


Here's GM's Service Bulletin:

Driveline - Clunk Explanation
File In Section: 04 - Driveline Axle
Bulletin No.: 99-04-20-002A
Date: September, 2001
INFORMATION
Subject:
Driveline Clunk
Models:
2002 and Prior Light Duty Truck Models
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number 99-04-20-002 (Section 04 - Driveline/Axle).
Important: The condition described in this bulletin should not be confused with Driveline Stop Clunk, described in Corporate Bulletin Number 964101R (Chevrolet 92-265-7A, GMC Truck 91-4A-77, Oldsmobile 47-71-20A, GM of Canada 93-4A-100) or Bump/Clunk Upon Acceleration, described in Corporate Bulletin Number 99-04-21-004.
Some owners of light duty trucks equipped with automatic transmissions may comment that the vehicle exhibits a clunk noise when shifting between Park and Drive, Park and Reverse, or Drive and Reverse. Similarly, owners of vehicles equipped with automatic or manual transmissions may comment that the vehicle exhibits a clunk noise while driving when the accelerator is quickly depressed and then released.
Whenever there are two or more gears interacting with one another, there must be a certain amount of clearance between those gears in order for the gears to operate properly. This clearance or freeplay (also known as lash) can translate into a clunk noise whenever the gear is loaded and unloaded quickly, or whenever the direction of rotation is reversed. The more gears you have in a system, the more freeplay the total system will have.
The clunk noise that owners sometimes hear may be the result of a buildup of freeplay (lash) between the components in the driveline.
For example, the potential for a driveline clunk would be greater in a 4-wheel drive or all-wheel drive vehicle than a 2-wheel drive vehicle. This is because in addition to the freeplay from the rear axle gears, the universal joints, and the transmission (common to both vehicles), the 4-wheel drive transfer case gears (and their associated clearances) add additional freeplay to the driveline.
In service, dealers are discouraged from attempting to repair driveline clunk conditions for the following reasons:
Comments of driveline clunk are almost never the result of one individual component with excessive lash, but rather the result of the added affect of freeplay (or lash) present in all of the driveline components.
Because all of the components in the driveline have a certain amount of lash by design, changing driveline components may not result in a satisfactory lash reduction.
While some owners may find the clunk noise objectionable, this will not adversely affect durability or performance.

I have the clunk when shifting into reverse. Will there ever be a solution to this problem from GM????

[fourwd84]

silvered:

i have the exact same truck as you and i have also noticed the "bouncing" thing when going down hill in cruise control. the clunk noise is quite familiar to me now as well...and just as annoying.

naked avalanche:

tell us more about the programmer and how it helped smooth things out.

[rositis]

yeah, just letting yall know that i am having the same problem with my truck. at first i thought it was comming from the rear end but now im not sure. in my truck its the loudest when i am starting off from a dead stop but only if the vehicle has rolled back some, like on a small incline. the dealer told me it was the brakes and not to worry cause it dosent do it all the time. i guess we will just have to wait and see what gm decides to do about it. i hope that it does not affect durability. oh and i have 4500 miles on my truck and it has been doing it noticably since about 1000 miles.