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second to third, third to second clunk or loud shift noise

psuduo

Full Member
Joined
Jan 7, 2005
Messages
33
When I SLOWLY drive and the av upshifts from second to third or downshifts from third to second (of the automatic transmission), I have a loud clunk or loud shifting noise.

Note, if I accelerate rapidly, this noise is not heard.

Is this normal or have any of you experienced this?? If it is not normal and you had the same problem, please recommend a remedy.

A QUESTION WAS ASKED WHAT YEAR, ETC.  2003, Z71, 1500, 4X4. 

ALSO, I HAVE A LOUD CLUNK WHEN I SHIFT INTO REVERSE.  I WAS TOLD THIS IS NORMAL, ALTHOUGH IT SOUNDS HORRIBLE.  A SERVICE ADVISOR WENT FOR A RIDE WITH ME AND TOLD ME THAT THE SOUND OF SHIFTING INTO REVERSE, FROM PARK OR ANY DRIVE GEARS IS NORMAL AND IT OCCURS EVEN LOUDER WITH HIS TAHOE.  SO MUCH SO IS THE REVERSE LASH NOISE NORMAL, THAT HE PRODUCED A GM TECHNICAL BULLITIN THAT INDICATES THAT IT IS A NORMAL NOISE WHEN SHIFTING INTO REVERSE.  HOWEVER, THE REVERSE NOISE IS A DIFFERENT NOISE FROM THE 2 TO 3 OR 3 TO 2 NOISE.

ANOTHER PERSON ASKED WHERE I AM FROM IN PA.  I LIVE IN SCHUYLKILL COUNTY PA, 10 MINUTES NORTH OF THE NEW CABELAS OUTDOORS STORE WHICH IS AT THE HAMBURG EXIT OF RTE. 78.  SCHUYLKILL COUNTY IS ALSO THE HOME OF YUENGLING BEER.  SPECIFICALLY, I AM IN NEW RINGGOLD, PENNSYLVANIA.



Thank you,
Bob in PA
:B:
 
What year?

1500 or 2500?

4x4 or 2x4?
 
Where in Pa. do you live ,I got same problem and more.I'm in lemon process now.I had GM engineer go for a ride and he said all GM trucks do this.Well I had enough lies.
 
Mine ('02 1500 4X4) does the same thing from 1st to 2nd, and from 2nd to 3rd.  Both during the up and down shifts.  I have had it in twice:

First time they said they couldn't reproduce....B.S.
Second time, the replaced some electronic signaling device....still didn't fix it
 
ACE Z71 said:
Where in Pa. do you live ,I got same problem and more.I'm in lemon process now.I had GM engineer go for a ride and he said all GM trucks do this.Well I had enough lies.

Schuylkill County, PA, specifically New Ringgold, PA...not too far from Jim Thorpe
 
Document ID# 1430424
2003 Chevrolet Avalanche - 4WD​

Information on 2-3 Upshift or 3-2 Downshift Clunk Noise #01-07-30-042B - (Jan 16, 2004)

2004 and Prior Light Duty Trucks

2003-2004 HUMMER H2

with 4L60E or 4L65E Automatic Transmission (RPOs M30, M32)

This bulletin is being revised to add the 2004 model year. Please discard Corporate Bulletin Number 01-07-30-042A (Section 07 - Transmission/Transaxle).

Some vehicles may exhibit a clunk noise that can be heard on a 2-3 upshift or a 3-2 downshift.

During a 2-3 upshift, the 2-4 band is released and the 3-4 clutch is applied. The timing of this shift can cause a momentary torque reversal of the output shaft that results in a clunk noise. This same torque reversal can also occur on a 3-2 downshift when the 3-4 clutch is released and the 2-4 band applied. This condition may be worse on a 4-wheel drive vehicle due to the additional tolerances in the transfer case.

This is a normal condition. No repairs should be attempted.

BULL! If it's "normal" why is it my 03 Z71 doesn't do it? Anyone else?
 
Thanks for that bulletin sperry (y) I thought my transmission was about to fall out. I hear the clunk when I'm cruising and it shifts from 2 to 3. I don't hear it on a down shift. When I'm hard accelerating I don't hear it at all.
 
Mine does it (always has) on the downshift and I HATE IT! :7: I've never been sure if it was the tranny or something with that freakin' G80 locker! Hate that too. :8:
 
Anyone up for another noise?  What about a thump noise when you come to a complete stop?  This noise occurs slightly after the complete stop and usually is louder when you stop rapidly.  This happens to me especially when I need to stop quick for a yellow light that I can't run in time.
Bob in PA
:B:

PS - For Mr. Jim Thorpe, let me know when you are on the way through New Ringgold, maybe we can get together.
 
See if there's a reprogram update for the trans..

------------------------
txyank1

Maybe look into that locker. Mine's working normal and so should your's of course.

I checked it out on some black ice in an empty parking lot. Bam! And released when it was supposed to.

Any of these?

Symptom List:

  ? Locking Rear Axle Does Not Lock
  ? Locking Rear Axle Locks in Turns
  ? Limited Slip Differential Chatters in Turns
  ? Locking Rear Drive Axle Chatters in Turns
  ? Noise in Addition to Normal Clutch Engagement
------------------------
 
psuduo said:
Anyone up for another noise?? What about a thump noise when you come to a complete stop?? This noise occurs slightly after the complete stop and usually is louder when you stop rapidly.? This happens to me especially when I need to stop quick for a yellow light that I can't run in time.
Bob in PA
:B:

PS - For Mr. Jim Thorpe, let me know when you are on the way through New Ringgold, maybe we can get together.
Mine does that too, but it would stop after awhile.
 
I've been hearing a light clunk when upshifting about 18 mph for 42K miles now.  Dealer / mechanic took it home for the night and said he didn't hear any clunks.
 
psuduo said:
Anyone up for another noise?? What about a thump noise when you come to a complete stop?? This noise occurs slightly after the complete stop and usually is louder when you stop rapidly.? This happens to me especially when I need to stop quick for a yellow light that I can't run in time.
Bob in PA
:B:
That would be the beer keg in the back. >:D
 
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