popping noise from frame rails

[litman2003]

Has anyone else heard a popping sound from the frane rails? I hear it now and again. It sounds like metal contracting or expanding. I know the sound of the air level system and this is not it. Please advise. Thanks

[litman2003]

Has anyone else heard a popping sound from the frane rails? I hear it now and again. It sounds like metal contracting or expanding. I know the sound of the air level system and this is not it. Please advise. Thanks

[OLE YLLR]

COULD IT BE THE CATALYTIC CONVERTER COOLING DOWN.

[JJ]

I've not heard the frame pop (except on my '95 Ford pickup - design problem). I have heard popping from the catalytic converter per OLE YLLR's post. Do you hear the popping while you are driving the vehicle or after you have parked it and turned the engine off or.....?

JJ

[SOFTTAILJC]

i hear the popping when i park in garage, if its real cold out and i come in warm garage... but not all the time..i wouldn't worry about it..just sounds like metal contacting.......soft.... --so nice that the flames went out!!!!

[Mango]

It's the exhaust system cooling down and making a pinging sound.

Mango -- Saltwater Flyfisherman, Photographer, Varmint Hunter -- Fort Worth, Tx

"They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety."

[litman2003]

The noise seems to come from all parts of the car. I hear it while driving ( well at a stop sign) I also, here it really loudly when I get out and she is stopped, it sounds like metal cooling. Nobody else hears anything like this??

[DelawareH2]

Actually, mine started doing the same thing just last week. It is not just from the catalytic converter. It seems to come from the whole exhaust system in different spots. It wouldn't be os irritating if it wasn't so loud. As soon as I stop at a light, the popping starts.

I have to take it in for service next week and I plan on having the dealer look at it.

[Big Drew]

I bought my black H2 at the end of Jan '02 and have the same problem. Hate that popping. Now I have another new one: I have a sunroof, and a loud knocking occurs underway, from somewhere to the front of the sunroof...thinking it could be the wind-deflector. Anyone else with this too?

I'VE HAD A FEW CLOSE SHAVES...

[Klaus]

Document ID # 1215842
2003 HUMMER H2

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

Exhaust/Muffler Heat Shield Rattle, Popping Noise Under Vehicle (Install Heat Shield Retaining Straps on Muffler) #02-06-05-005A - (12/19/2002)
Exhaust/Muffler Heat Shield Rattle, Popping Noise Under Vehicle (Install Heat Shield Retaining Straps On Muffler)
2002-2003 Cadillac Escalade, Escalade EXT

2000-2003 Chevrolet Silverado, Suburban

2002-2003 Chevrolet Avalanche

2000-2003 GMC Denali, Denali XL, Sierra, Yukon XL

2003 HUMMER H2

with 5.3L or 6.0L Gas Engine (VINs T, N -- RPOs LM7, LQ9)

Except 1500 Series Models

This bulletin is being revised to add Models information. Please discard Corporate Bulletin 02-06-05-005 (Section 06 -- Engine/Propulsion System).

Condition
Some customers may comment on a rattle/popping noise from under the vehicle.

Cause
The separation of the muffler heat shield from the muffler may cause a rattle under the vehicle.

Correction
Install two heat shield retaining straps, P/N 15164621, to the muffler and muffler heat shield. Follow the service procedure below to correct this concern.

Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle (SI Document ID #737171).



Install a retaining strap, P/N 15164621, around the front of the muffler and muffler heat shield as shown above.
Pull the retaining strap tight with one hand and tighten the Allen head screw with the other hand. Tighten
Tighten the Allen head screw on the retaining strap to 13.5 N·m (119 lb in).

Repeat steps 2 and 3 on the rear of the muffler.
Lower the vehicle.
Parts Information
Part Number
Description
Qty

15164621
Strap Asm-Exhaust Muffler Heat Shield
2


Parts are currently available from GMSPO.

Warranty Information
For vehicles repaired under warranty, use:

Labor Operation
Description
Labor Time

*L2540
Shield, Muffler Retaining Clamp - Install
0.2 hr

*This is a unique labor operation number for use only with this bulletin. The number will not be published in the Labor Time Guide.




GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information. WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

© Copyright General Motors Corporation. All Rights Reserved.


--------------------------------------------------------------------------------
Document ID # 1215842
2003 HUMMER H2

[Hum2]

Keep 'em coming.....thanks Klaus!

Ric
OMAHOG/IHOG

[HummerN23]

has anyone had this service bulletin fix done on their H2? Local dealer says that 'noise is normal expamsion of metals due to heat and ambient air temp-no fix at this time' even after telling them to look for the bulletin.

[Texas Red]

I would say if dealer doesn't acknowledge or work in accordance with service bulletin, you should tell general manager you will be calling Hummer Customer Service.

Jim
Red H2

[DURAMAX TIM]

I just heard the 'popping' sound Tuesday nite,
I knew it was exhaust related but I have owned at least 8 of the vehicles on the tech sheet and didn't have sound from them.
I'll have to slide under it and see whats doing it then get dealer to order the parts on tech sheet.

[Steve R]

Klaus.....you da man!!!

As for popping and other noises...ain't nothing a loud stereo can't resolve!

[HummerN23]

Not quite, it is very loud, especially after shutoff. when walking through a large 1500 car parking garage you can hear it at the other end from where I park. seeing how it is one of 1500 doing it, I'd hardly call that normal. I can even hear it when stopped at traffic lights. You should see the looks on people's faces when they are stopped next to me, drool dribbling down their chins, when they hear 'POP TWANG".

[DROPER]

I have had this problem on my GM truck too. It sounds like the cat or muffler cooling down and the metal pops back. I never got my truck fixed (even though it was in warranty) but it was darn annoying.

I plan to add it to my list.

[Hum2me]

Also have the popping even when running and sitting at a light. I have an apt Friday to check it out, I assume the Dealer's now are aware of the popping??????

[Hum2me]

Dealer said thats normal, well I am sure as I visit another dealer during my service I will try again!!<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hum2me:
Also have the popping even when running and sitting at a light. I have an apt Friday to check it out, I assume the Dealer's now are aware of the popping??????<HR></BLOCKQUOTE>

[HummerN23]

I just got my H2 back this week and the dealer claimed to have completed the service bulletin. I'll have to slide under there to see, cause the noise is still there, but it is a tad quieter. Not loud enough to wake the dead but still not what I'd expect from a Hummer.