Loud Vibration Passenger Floor board
r7069c
01-11-2006, 04:54 PM
I just purchased a 99 Tahoe 2 door Z71 with 72k miles. I had to replace the front drivers side CV joint and HUb Assembly initially. I also had to replace the brake bads and rotors. The rotor on the drivers side was warped due to the bad CV joint and Hub (Bearing)assembly. I am still getting a loud vibration noise coming up thru the floorboard when I accelerate. Note: This sound only happens when accelerating. The sound itslef usually only last a second. This mostly happens at lower speeds or when I am first taking off. It doesn't happen while shifting to a higher gear. It seems to be more prominent on the passenger side floor board. IT also seems to be coming from the passenger side of the transmission. It doesn't matter what gear I'm in or If I am in 4x4 or 2 wheel drive. Any Help?
Update: I may have found the problem. I had the service manager from one of the local dealerships look thru the TSB reports on my vehicle. Here is what he found.
Exhaust System Rumble/Rattle Noise (Replace Exhaust Pipe Seals and Modify Exhaust Pipe Ring Flanges) #01-06-05-006 - (Nov 2, 2001)
Exhaust System Rumble/Rattle Noise (Replace Exhaust Pipe Seals and Modify Exhaust Pipe Ring Flanges)
1996-1998 Chevrolet and GMC C/K Models with 4.3L Engine (VIN W -- RPO L35)
1996-1999 Chevrolet and GMC C/K Models (Old Style) with 5.0L or 5.7L Engine (VINs M, R -- RPOs L30, L31)
2000 Chevrolet and GMC C/K Models (Old Style) with 5.7L Engine (VIN R -- RPO L31)
1996-2002 Chevrolet and GMC G-Vans with 4.3L, 5.0L or 5.7L Engine (VINs W, M, R -- RPOs L35, L30 or L31)
1996-2002 Chevrolet and GMC S/T, M/L Models with 4.3L Engine (VIN W -- RPO L35)
1999-2000 Cadillac Escalade
1996-2002 Oldsmobile Bravada
Condition
Some customers may comment on a rumble/rattle-type noise that is audible in the vehicle passenger compartment when the engine is idling, the transmission is in Drive and the service brakes are applied. High ambient temperatures and A/C compressor cycling may further aggravate this condition.
Cause
This condition may be the result of inadequate clampload on the exhaust pipe seals at the exhaust pipe/manifold joint. The low seal clampload may be the result of the standoffs on either one or both of the exhaust pipe ring flanges contacting the exhaust manifold.
Correction
This condition can be corrected by replacing the existing exhaust pipe seals with new seals, P/N 15093974, and modifying the exhaust pipe ring flanges. The ring flange modification consists of reducing the height of all three of the standoffs on both of the exhaust pipe ring flanges by 2 mm (0.08 in). Follow the procedure below.
1.. Following the Service Manual procedure, lower the exhaust system down enough to access the exhaust pipe ring flanges.
2.. Remove and discard the existing exhaust pipe seals.
3.. With the ring flanges slid down the exhaust pipe, mark each of the three standoffs on both the rings 2 mm (0.08 in) down from the surface that faces the exhaust manifold.
4.. Grind the ring flange standoffs to the marks established in the previous step on both of the flanges.
5.. Install new exhaust pipe seals, P/N 15093974.
6.. Raise the exhaust pipe into position and hand start the ring flange to exhaust manifold fasteners.
Notice: Use the tightening sequence and specifications indicated below when installing fasteners in order to avoid damage to parts and systems. If exhaust system is disconnected at any location other than at the exhaust seal , gasket and exhaust system alignment may be required.
7.. Following the fastener tightening sequence, gradually draw the ring flanges toward the exhaust manifold seal faces, maintaining the ring flanges as parallel to the manifold faces as possible.
Tighten
Tighten the exhaust ring flange to exhaust manifold fasteners to the specification indicated below by vehicle year and model.
Year/Model
Tightening Specification
1996-02 S/T-Truck
53 N·m (39 lb ft)
1996-02 M/L-Van
53 N·m (39 lb ft)
1996-97 C/K-Truck (Old Style)
48 N·m (35 lb ft)
1998-00 C/K-Truck (Old Style)
64 N·m (47 lb ft)
1996-02 G-Van
65 N·m (48 lb ft)
Parts Information
Part Number
Description
Qty
15093974
Seal - Exhaust Manifold Pipe
2
Parts are currently available from GMSPO.
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
Update: I may have found the problem. I had the service manager from one of the local dealerships look thru the TSB reports on my vehicle. Here is what he found.
Exhaust System Rumble/Rattle Noise (Replace Exhaust Pipe Seals and Modify Exhaust Pipe Ring Flanges) #01-06-05-006 - (Nov 2, 2001)
Exhaust System Rumble/Rattle Noise (Replace Exhaust Pipe Seals and Modify Exhaust Pipe Ring Flanges)
1996-1998 Chevrolet and GMC C/K Models with 4.3L Engine (VIN W -- RPO L35)
1996-1999 Chevrolet and GMC C/K Models (Old Style) with 5.0L or 5.7L Engine (VINs M, R -- RPOs L30, L31)
2000 Chevrolet and GMC C/K Models (Old Style) with 5.7L Engine (VIN R -- RPO L31)
1996-2002 Chevrolet and GMC G-Vans with 4.3L, 5.0L or 5.7L Engine (VINs W, M, R -- RPOs L35, L30 or L31)
1996-2002 Chevrolet and GMC S/T, M/L Models with 4.3L Engine (VIN W -- RPO L35)
1999-2000 Cadillac Escalade
1996-2002 Oldsmobile Bravada
Condition
Some customers may comment on a rumble/rattle-type noise that is audible in the vehicle passenger compartment when the engine is idling, the transmission is in Drive and the service brakes are applied. High ambient temperatures and A/C compressor cycling may further aggravate this condition.
Cause
This condition may be the result of inadequate clampload on the exhaust pipe seals at the exhaust pipe/manifold joint. The low seal clampload may be the result of the standoffs on either one or both of the exhaust pipe ring flanges contacting the exhaust manifold.
Correction
This condition can be corrected by replacing the existing exhaust pipe seals with new seals, P/N 15093974, and modifying the exhaust pipe ring flanges. The ring flange modification consists of reducing the height of all three of the standoffs on both of the exhaust pipe ring flanges by 2 mm (0.08 in). Follow the procedure below.
1.. Following the Service Manual procedure, lower the exhaust system down enough to access the exhaust pipe ring flanges.
2.. Remove and discard the existing exhaust pipe seals.
3.. With the ring flanges slid down the exhaust pipe, mark each of the three standoffs on both the rings 2 mm (0.08 in) down from the surface that faces the exhaust manifold.
4.. Grind the ring flange standoffs to the marks established in the previous step on both of the flanges.
5.. Install new exhaust pipe seals, P/N 15093974.
6.. Raise the exhaust pipe into position and hand start the ring flange to exhaust manifold fasteners.
Notice: Use the tightening sequence and specifications indicated below when installing fasteners in order to avoid damage to parts and systems. If exhaust system is disconnected at any location other than at the exhaust seal , gasket and exhaust system alignment may be required.
7.. Following the fastener tightening sequence, gradually draw the ring flanges toward the exhaust manifold seal faces, maintaining the ring flanges as parallel to the manifold faces as possible.
Tighten
Tighten the exhaust ring flange to exhaust manifold fasteners to the specification indicated below by vehicle year and model.
Year/Model
Tightening Specification
1996-02 S/T-Truck
53 N·m (39 lb ft)
1996-02 M/L-Van
53 N·m (39 lb ft)
1996-97 C/K-Truck (Old Style)
48 N·m (35 lb ft)
1998-00 C/K-Truck (Old Style)
64 N·m (47 lb ft)
1996-02 G-Van
65 N·m (48 lb ft)
Parts Information
Part Number
Description
Qty
15093974
Seal - Exhaust Manifold Pipe
2
Parts are currently available from GMSPO.
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
r7069c
01-30-2006, 03:08 PM
Update--- Took it to the muffler shop. Turns out that whoever placed the muffler on before attached it too close to the front of the vehicle. This in turn put the muffler too close to the heat shield. The muffler was vibrating against the heatshield. Took $40 to fix. Finally
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