Exhaust Moan / Vibration

generatormd · January 7, 2008

2002 2500hd 8.1l 4x4

I have a maon / vibration at 2000 rpm 55-60 mph. I has to be at that speed and rpm to getthis to hapen. I can feel it in the floor (very little). I have seen other post about installing flex pipe?

Have installed a new muffler and inspected all the heat shields.

Mudddawg · January 8, 2008

2002 2500hd 8.1l 4x4

I have a maon / vibration at 2000 rpm 55-60 mph. I has to be at that speed and rpm to getthis to hapen. I can feel it in the floor (very little). I have seen other post about installing flex pipe?

Have installed a new muffler and inspected all the heat shields.

MY TRUCK DONE THIS ALSO. ALTHOUGH MY TRUCK HAS THE 6.0 I THINK THE MUFFLER (MIGHT) BE THE SAME. I WAS TOLD THAT IT WAS, BELIEVE THIS OR NOT, POOR BAFFLE DESIGN CAUSING THE EXHUAST TO VIBRATE. THAT IS WHAT THE DEALER TOLD MY FRIEND WHO HAS THE SAME TRUCK AS ME. HE HAD TWO NEW MUFFLERS INSTALLED BY DEALER, SAME PROBLEM PERSISTED. DO AS WE DID, INSTALL FLOWMASTER. HOPW THIS HELPS!!

cerbomark · January 8, 2008

if you removed or don t have the resonator it can do this. Just a fact of the 6.0 or anything larger.

generatormd · January 10, 2008

2002 2500hd 8.1l 4x4

I have a maon / vibration at 2000 rpm 55-60 mph. I has to be at that speed and rpm to getthis to hapen. I can feel it in the floor (very little). I have seen other post about installing flex pipe?

Have installed a new muffler and inspected all the heat shields.

MY TRUCK DONE THIS ALSO. ALTHOUGH MY TRUCK HAS THE 6.0 I THINK THE MUFFLER (MIGHT) BE THE SAME. I WAS TOLD THAT IT WAS, BELIEVE THIS OR NOT, POOR BAFFLE DESIGN CAUSING THE EXHUAST TO VIBRATE. THAT IS WHAT THE DEALER TOLD MY FRIEND WHO HAS THE SAME TRUCK AS ME. HE HAD TWO NEW MUFFLERS INSTALLED BY DEALER, SAME PROBLEM PERSISTED. DO AS WE DID, INSTALL FLOWMASTER. HOPW THIS HELPS!!

When I bought the truck it had a single flow master and it mad the same noise, except earlier in the RPM and it maintained for longer. So I replaced it with a Magnaflow. It’s much quieter. however the moaning has to go. I have read in some other post that GM has a flex pipe fix for this. However I have not been able to fin any info it. My truck has 2ea 3in pipes that go into a single muffler and then a single 3.5in exit. I have thought about putting duels on it; however of the local exhaust shops say I will have to relocate my spare tire. If I new that would fix the problem I would do it in heart beat.

minibike132 · January 10, 2008

The only flex pipe bulliten I can find is for a 4.3.

joe04 · January 10, 2008

The only flex pipe bulliten I can find is for a 4.3.

FYI I had a 04 1/2 ton 4wd that exhaust drove me crazy. Chev dealer said there were weights to clamp to exhaust pipe, basically a counterweight...to change the resonance. They ordered them, and put them on. No more resonance. Kind of tacky though...Probably find them with a search, I lost the tsb they printed out for it.

generatormd · January 11, 2008

The only flex pipe bulliten I can find is for a 4.3.

FYI I had a 04 1/2 ton 4wd that exhaust drove me crazy. Chev dealer said there were weights to clamp to exhaust pipe, basically a counterweight...to change the resonance. They ordered them, and put them on. No more resonance. Kind of tacky though...Probably find them with a search, I lost the tsb they printed out for it.

Weights? Well if works I don't car how it looks. Did you ever look and see where the weights were placed?

minibike132 · January 11, 2008

There is a preliminary bulliten that applies here (maybe) The diagnostic for it is rather complicated and involved. I was kind of warned about posting GM literature so I am no longer doing any of that but if you can find it it is PIP3121E or doc#1820205. Once the diagnostic has been performed and it is verified there is a 4th order vibration indicating a exhaust noise it suggests a fix. You would not be able to perform this diagnosis at home but if you can find the bulliten and want to throw the fix at the truck have at it.

joe04 · January 11, 2008

There is a preliminary bulliten that applies here (maybe) The diagnostic for it is rather complicated and involved. I was kind of warned about posting GM literature so I am no longer doing any of that but if you can find it it is PIP3121E or doc#1820205. Once the diagnostic has been performed and it is verified there is a 4th order vibration indicating a exhaust noise it suggests a fix. You would not be able to perform this diagnosis at home but if you can find the bulliten and want to throw the fix at the truck have at it.

Found it. Document ID# 1820205

Subject: Exhaust Vibration,Resonance,or moan.

Also look for #PIP3121E (04/24/06)

Includes:

01-06Cad Escalade

02-06 Chev Av

99-06 Chev Silv

00-06 Chev Sub, Tahoe

99-06 GMC Sierra

00-06 GMC Yukon

03-06 Hummer

Condition is listed as "some 99-06 with single exhaust system may exhibit exhaust vibration that is engine load sensitive. Typically, this will happen just off idle to 2000 RPM on light acceleration."

Hope this helps!!

johnbob · January 14, 2008

There is a preliminary bulliten that applies here (maybe) The diagnostic for it is rather complicated and involved. I was kind of warned about posting GM literature so I am no longer doing any of that but if you can find it it is PIP3121E or doc#1820205. Once the diagnostic has been performed and it is verified there is a 4th order vibration indicating a exhaust noise it suggests a fix. You would not be able to perform this diagnosis at home but if you can find the bulliten and want to throw the fix at the truck have at it.

Found it. Document ID# 1820205

Subject: Exhaust Vibration,Resonance,or moan.

Also look for #PIP3121E (04/24/06)

Includes:

01-06Cad Escalade

02-06 Chev Av

99-06 Chev Silv

00-06 Chev Sub, Tahoe

99-06 GMC Sierra

00-06 GMC Yukon

03-06 Hummer

Condition is listed as "some 99-06 with single exhaust system may exhibit exhaust vibration that is engine load sensitive. Typically, this will happen just off idle to 2000 RPM on light acceleration."

Hope this helps!!

johnbob · January 14, 2008

There is a preliminary bulliten that applies here (maybe) The diagnostic for it is rather complicated and involved. I was kind of warned about posting GM literature so I am no longer doing any of that but if you can find it it is PIP3121E or doc#1820205. Once the diagnostic has been performed and it is verified there is a 4th order vibration indicating a exhaust noise it suggests a fix. You would not be able to perform this diagnosis at home but if you can find the bulliten and want to throw the fix at the truck have at it.

Found it. Document ID# 1820205

Subject: Exhaust Vibration,Resonance,or moan.

Also look for #PIP3121E (04/24/06)

Includes:

01-06Cad Escalade

02-06 Chev Av

99-06 Chev Silv

00-06 Chev Sub, Tahoe

99-06 GMC Sierra

00-06 GMC Yukon

03-06 Hummer

Condition is listed as "some 99-06 with single exhaust system may exhibit exhaust vibration that is engine load sensitive. Typically, this will happen just off idle to 2000 RPM on light acceleration."

Hope this helps!!

Please tell me the website that you use these PIP and DOC numbers with. I can't find one that uses them.

Thanks.

joe04 · January 14, 2008

There is a preliminary bulliten that applies here (maybe) The diagnostic for it is rather complicated and involved. I was kind of warned about posting GM literature so I am no longer doing any of that but if you can find it it is PIP3121E or doc#1820205. Once the diagnostic has been performed and it is verified there is a 4th order vibration indicating a exhaust noise it suggests a fix. You would not be able to perform this diagnosis at home but if you can find the bulliten and want to throw the fix at the truck have at it.

Found it. Document ID# 1820205

Subject: Exhaust Vibration,Resonance,or moan.

Also look for #PIP3121E (04/24/06)

Includes:

01-06Cad Escalade

02-06 Chev Av

99-06 Chev Silv

00-06 Chev Sub, Tahoe

99-06 GMC Sierra

00-06 GMC Yukon

03-06 Hummer

Condition is listed as "some 99-06 with single exhaust system may exhibit exhaust vibration that is engine load sensitive. Typically, this will happen just off idle to 2000 RPM on light acceleration."

Hope this helps!!

Please tell me the website that you use these PIP and DOC numbers with. I can't find one that uses them.

Thanks.

Sorry, Maybe someone else will be able to help. I just copied what my dealer printed out for me to read.