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Chevrolet Silverado / GMC Sierra. Manual - part 1400
CONSTANT NOISE
Checks
Action
Warped ring gear
Replace the ring gear. Refer to Drive Pinion and Ring Gear
Replacement (8.6, 9.5/9.5LD, and 11.5 Inch Axles) or
Drive Pinion and Ring Gear Replacement (10.5 Inch
Axle)
.
Loose differential case bolts Tighten differential case bolts to specifications. Refer to
Fastener Tightening Specifications.
Cause
Correction
DEFINITION: A noise heard in the rear axle during all driving conditions. This noise may
increase or decrease in volume based on different driving maneuvers and speeds.
Flat spot on the pinion or the
ring gear teeth
Replace the pinion and the ring gear. Refer to Drive Pinion
and Ring Gear Replacement (8.6, 9.5/9.5LD, and 11.5
Inch Axles) or Drive Pinion and Ring Gear Replacement
(10.5 Inch Axle).
Flat spot on the pinion
bearing
Replace the bearing. Refer to Drive Pinion Bearings
Replacement (8.6, 9.5, 11.5 Inch Axle) or Drive Pinion
Bearings Replacement (10.5 Inch Axle).
Worn pinion splines
Replace the pinion. Refer to Drive Pinion and Ring Gear
Replacement (8.6, 9.5/9.5LD, and 11.5 Inch Axles) or
Drive Pinion and Ring Gear Replacement (10.5 Inch
Axle).
Low oil level
Fill the fluid level to specifications with the proper lubricant.
Refer to Rear Axle Lubricant Level Inspection (11.5 Inch
Axle) or Rear Axle Lubricant Level Inspection (8.6, 9.5
LD Axle) or Rear Axle Lubricant Level Inspection (10.5
Inch Axle).
Wrong or poor grade oil
Drain and refill the system with the proper lubricant. Refer to
Rear Axle Lubricant Replacement (8.6 Inch Axle) or
Rear Axle Lubricant Replacement (9.5 Inch LD Axle) or
Rear Axle Lubricant Replacement (10.5 Inch Axle).
Excessive pinion to ring gear
backlash
Adjust the pinion to ring gear backlash. Refer to Backlash
Adjustment (8.6 Inch Axle) or Backlash Adjustment
(10.5, 11.5 Inch Axles) or Backlash Adjustment (9.5 LD
Axle).
Adjust the pinion bearings preload. Refer to Pinion Depth
2008 Chevrolet Silverado 1500
2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Loose pinion bearings
Adjustment (10.5 Inch Axle) or Pinion Depth Adjustment
(8.6, 9.5/9.5LD, and 11.5 Inch Axles).
Excessive pinion end play
Adjust the pinion end play. Refer to Pinion Depth
Adjustment (10.5 Inch Axle) or Pinion Depth Adjustment
(8.6, 9.5/9.5LD, and 11.5 Inch Axles).
Incorrect differential
bearing preload
Adjust the differential bearing preload. Refer to Differential
Carrier Bearing Preload Adjustment (10.5 Inch, 11.5
Inch Axles) or
Differential Carrier Bearing Preload
Adjustment (8.6 Inch Axle)
or Differential Carrier
Bearing Preload Adjustment (9.5, and 9.5LD Inch Axles).
Incorrect backlash
Adjust the pinion and ring gear backlash. Refer to Backlash
Adjustment (8.6 Inch Axle) or Backlash Adjustment
(10.5, 11.5 Inch Axles) or Backlash Adjustment (9.5 LD
Axle).
Worn pinion bearings
Replace the pinion bearings. Refer to Drive Pinion Bearings
Replacement (8.6, 9.5, 11.5 Inch Axle) or Drive Pinion
Bearings Replacement (10.5 Inch Axle).
Worn differential bearings
Replace the differential bearings. Refer to Differential Side
Bearings Replacement (All Except 9.75 Inch Axle).
Worn pinion and ring gear
Replace the pinion and ring gear. Refer to Drive Pinion and
Ring Gear Replacement (8.6, 9.5/9.5LD, and 11.5 Inch
Axles) or Drive Pinion and Ring Gear Replacement (10.5
Inch Axle).
Excessive ring gear runout
Replace the ring gear. Refer to Drive Pinion and Ring Gear
Replacement (8.6, 9.5/9.5LD, and 11.5 Inch Axles) or
Drive Pinion and Ring Gear Replacement (10.5 Inch
Axle).
Bent axle housing
Replace the axle housing. Refer to Rear Axle Housing
Replacement (w/Rear Drum) or Rear Axle Housing
Replacement (w/Rear Disc ).
Worn axle shaft dowel holes Replace the axle shaft. Refer to Rear Axle Shaft
Replacement (8.6 Inch Axle w/Drum Brake w/VSES) or
Rear Axle Shaft Replacement (8.6 Inch Axle w/Drum
Brakes w/o VSES) or Rear Axle Shaft Replacement (8.6,
9.5 Inch Axles w/VSES) or to Rear Axle Shaft and/or
Gasket Replacement.
Worn hub studs
Replace the wheel studs. Refer to Wheel Stud
2008 Chevrolet Silverado 1500
2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
NOISY ON TURNS
WHEEL BEARING WEAR - REAR DRIVE AXLE (STRAIGHT)
Straight Roller Bearing Diagnosis
Consider the following factors when diagnosing a bearing condition:
Note the general condition of all parts during disassembly and inspection.
Classify the failure with the aid of the illustrations.
Determine the cause.
Make all repairs following recommended procedures.
Wear (Minor)
Replacement .
Bent axle shaft
Replace the axle shaft. Refer to Rear Axle Shaft
Replacement (8.6 Inch Axle w/Drum Brake w/VSES) or
Rear Axle Shaft Replacement (8.6 Inch Axle w/Drum
Brakes w/o VSES) or Rear Axle Shaft Replacement (8.6,
9.5 Inch Axles w/VSES) or Rear Axle Shaft and/or Gasket
Replacement.
Checks
Action
Worn differential side gears
and pinions
Replace the differential side gears and pinions. Refer to
Differential Overhaul (11.5 Inch Axle) or Differential
Overhaul (9.5/9.5LD Inch Axles) or Differential Overhaul
(8.6 Inch Axle) or Differential Overhaul (10.5 Inch Axle).
Worn differential spider
gears
Replace the spider gears. Refer to Differential Overhaul
(11.5 Inch Axle) or Differential Overhaul (9.5/9.5LD Inch
Axles) or Differential Overhaul (8.6 Inch Axle) or
Differential Overhaul (10.5 Inch Axle).
Worn axle shaft splines
Replace the axle shaft. Refer to Rear Axle Shaft
Replacement (8.6 Inch Axle w/Drum Brake w/VSES) or
Rear Axle Shaft Replacement (8.6 Inch Axle w/Drum
Brakes w/o VSES) or Rear Axle Shaft Replacement (8.6,
9.5 Inch Axles w/VSES) or Rear Axle Shaft and/or Gasket
Replacement.
2008 Chevrolet Silverado 1500
2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Fig. 6: Identifying Minor Wear
Courtesy of GENERAL MOTORS CORP.
Light pattern on races and rollers can be caused by fine abrasives. Clean all of the parts including
the housings. Check the seals. Replace the bearings if rough or noisy. Replace the shaft if
damaged.
Wear (Major)
2008 Chevrolet Silverado 1500
2008 Driveline/Axle Rear Drive Axle - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Content .. 1398 1399 1400 1401 ..