Transfer Case?

LuxuriesPremier · January 11, 2008

Hey guys I recently noticed that when i push up on the driveshaft near the transfer case I hear a click coming from inside the transfer case itself.. Is this something that is normal or just another GM only issue? I am still looking for the reason why the truck starts vibrating at around 65 and get noticeably intense at 80-85. I have already replaced Tires, u-joints, and entire Rear-End. I guess i am just looking for something to place blame on next lol. If this clicking noise is not normal can i get an aftermarket rebuildkit or something stronger than OEM? I am not very happy with the quaility of parts so far on this truck and would rather go for aftermarket... Thx in advance all input is appreciated

Truck info:

2000 GMC Sierra 4x4 Ext. Cab 6 1/2 foot bed 80K 3.73 gear ratio

Norseman · January 11, 2008

Hey guys I recently noticed that when i push up on the driveshaft near the transfer case I hear a click coming from inside the transfer case itself.. Is this something that is normal or just another GM only issue? I am still looking for the reason why the truck starts vibrating at around 65 and get noticeably intense at 80-85. I have already replaced Tires, u-joints, and entire Rear-End. I guess i am just looking for something to place blame on next lol. If this clicking noise is not normal can i get an aftermarket rebuildkit or something stronger than OEM? I am not very happy with the quaility of parts so far on this truck and would rather go for aftermarket... Thx in advance all input is appreciated

Truck info:

2000 GMC Sierra 4x4 Ext. Cab 6 1/2 foot bed 80K 3.73 gear ratio

I'd take the truck somewhere that specializes in drive trains and have them look it over.

It would be kind of hard for any of us to help without being able to hear and see it.

Wish I had more. Sorry.

jrrod2004 · January 12, 2008

Here is some info that might be useful:

Document ID# 1962218

2000 GMC Truck GMC K Sierra - 4WD

Subject:Improved Oil Fluid Wear Pump Clip - keywords 136 149 246 246EAU 261 263 263EAU housing leak case transfer transfercase #PIP4118 - (04/17/2007)

Models:1998-2007 Light Duty Trucks and Utilities

Equipped with New Venture Gear Transfer Cases RPO NP1, NP2, NP3, NP4, NP8

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Oil pump wear clip P/N 12470559 is broken or out of position. This may cause the pump to wear a pin hole in the transfer case rear half. If the wear is severe the transfer case may be damaged due to lack of lubrication. The clip may fatigue and break. The clip may become loose and shift out of position.

Recommendation/Instructions:

A new clip design has been released. P/N 89059653 is available for both production and service. This new part totally cancels and supersedes the former P/N 12470559. Only the new clip will be available.

This new oil pump wear clip should be used whenever a transfer case is opened for any type of internal service. See photo. GMSPO currently has inventory of the new part.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

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

Document ID# 1962218

2000 GMC Truck GMC K Sierra - 4WD

Document ID# 2046711

2000 GMC Truck GMC K Sierra - 4WD

Subject:Suspension Vibration Or Frame Beaming At 40-60 (64-80 km/h) - keywords front rear shake shock spring tire #PIT3009F - (12/27/2007)

Models:1999-2007 Chevrolet Silverado Classic

1999-2007 GMC Sierra Classic

This PI was superseded to update information on what will be fixed. Please discard PIT3009E.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Beam shake vibration is usually felt in the seat and occurring at speeds between 40-50 mph (64 - 80 km/h). Hertz readings using an EVA tool are normally between 8-24 Hz. This condition is most common on extended cab and crew cab models but has also been noted in other models.

Recommendation/Instructions:

The severity of beam shake may vary from vehicle to vehicle. To determine if the concern is beam shake, please perform the following:

<LI type=1>Test drive vehicle to confirm the condition. A beam shake condition will usually respond to concrete type pavements more than asphalt, so the vehicle should be driven over both surfaces if possible.
Place 200-500 pounds in the pickup bed between the closed tailgate and the wheel wells. A beaming condition should dissipate.

Note: Tires with excessive Radial Force Variation (RFV) or out-of-roundness can intensify the frame beaming concern. The following radial force variation numbers should be used as a guide:

P-Metric tires (2wd 1500) 12 lbs or less

P-Metric tires (all others) 24 lbs or less

LT-tires 30 lbs or less

If the concern is determined to be beam shake, this is a characteristic of the vehicle and currently no repair attempts should be made. GM Engineering is currently working on reducing this concern for the light duty 1500 Crew and Extended Cab Models. There will be no changes made to the 1500 regular cab, 1500HD, 2500 or 3500 models.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

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

Document ID# 2046711

2000 GMC Truck GMC K Sierra - 4WD

Document ID# 2044877

2000 GMC Truck GMC K Sierra - 4WD

Subject:4WD Models With Noise Vibration On Dry Pavement - keywords grind growl moan rattle #PIP3300B - (12/13/2007)

Models:1996-2008 All Chevrolet and GMC Light Duty Trucks and Utilities

Equipped with 4WD

This PI was superseded to update model years. Please discard PIP3300A.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Groan, growl, or moan coming from the vehicle when operating the vehicle in four wheel drive.

Recommendation/Instructions:

The vibration that is heard or felt is a result of the front axle being excited to resonance at its natural frequency. This is a combination of: the transfer case chain link frequency, engine firing frequency, tire circumference variation, and various other tolerances built into the 4WD system.

ADDITIONAL NOTE #1:

A groan, growl or moan noise on deceleration while in 4WD is also the result of loading the transfer case chain which is an operating characteristic. This is just one example of a transfer case link frequency as noted above.

ADDITIONAL NOTE #2:

On certain models, such as 3/4 and 1 ton vehicle, tire pressures can vary from front to rear based on the manufacturer's specifications. As an example the manufacturer's specifications for tire pressures on a 03 K2500 Suburban are front: 50 PSI, rear: 80 PSI.

The difference in tire pressures affects the rolling tire circumference from front to rear which can increase driveline noise while in 4WD which is an operating characteristic.

For test purposes, drop the tire pressure in the rear to match the front. If the noise is reduced or eliminated this confirms the difference in tire pressures from front to rear can affect the noise when operated in 4WD. Set the rear tire pressure back to the manufacturer's specification. For vehicles with same tire pressures front to rear, swap tires from an identically built vehicle that does not seem to exhibit the concern and re-evaluate both vehicles.

No repairs are recommended for this condition.

For more information regarding driveline noises while in four wheel drive refer to the latest version of TSB 01-04-18-001D.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

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

Document ID# 2044877

2000 GMC Truck GMC K Sierra - 4WD

marko · January 12, 2008

M.Cueva it sounds like Dontech might be having the vibration problems set out in the TSB's you've posted. See this thread:

Vibration

Sounds like he could use your help!

Dontech · January 14, 2008

M.Cueva it sounds like Dontech might be having the vibration problems set out in the TSB's you've posted. See this thread:

Vibration

Sounds like he could use your help!

The beaming Tsb sounds closes to my Vib problem. This would be my luck having no fix.Today they are testing the drive shaft. They have had the truck over a week now.