Constant Noise

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

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 (10.5 Inch Axle) or Drive Pinion and Ring Gear Replacement (8.6 Inch Axle) .
Flat spot on the pinion bearing	Replace the bearing. Refer to Drive Pinion Bearings Replacement (8.6 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 (10.5 Inch Axle) or Drive Pinion and Ring Gear Replacement (8.6 Inch Axle) .
Low oil level	Fill the fluid level to specifications with the proper lubricant. Refer to Rear Axle Lubricant Level Inspection (8.6 Inch Axle) or Rear Axle Lubricant Level Inspection (9.5 Inch LD 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 (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 Inch Axle) .
Loose pinion bearings	Adjust the pinion bearings preload. Refer to Pinion Depth Adjustment (10.5 Inch Axle) or Pinion Depth Adjustment (8.6 Inch Axle) .
Excessive pinion end play	Adjust the pinion end play. Refer to Pinion Depth Adjustment (10.5 Inch Axle) or Pinion Depth Adjustment (8.6 Inch Axle) .
Incorrect differential bearing preload	Adjust the differential bearing preload. Refer to Differential Carrier Bearing Preload Adjustment (8.6 Inch Axle) or Differential Carrier Bearing Preload Adjustment (10.5 Inch Axle) .
Incorrect backlash	Adjust the pinion and ring gear backlash. Refer to Backlash Adjustment (8.6 Inch Axle) or Backlash Adjustment (10.5 Inch Axle) .
Worn pinion bearings	Replace the pinion bearings. Refer to Drive Pinion Bearings Replacement (8.6 Inch Axle) or Drive Pinion Bearings Replacement (10.5 Inch Axle) .
Worn differential bearings	Replace the differential bearings. Refer to Differential Side Bearings Replacement .
Worn pinion and ring gear	Replace the pinion and ring gear. Refer to Drive Pinion and Ring Gear Replacement (10.5 Inch Axle) or Drive Pinion and Ring Gear Replacement (8.6 Inch Axle) .
Excessive ring gear runout	Replace the ring gear. Refer to Drive Pinion and Ring Gear Replacement (10.5 Inch Axle) or Drive Pinion and Ring Gear Replacement (8.6 Inch Axle) .
Bent axle housing	Replace the axle housing. Refer to Rear Axle Housing Replacement .
Worn axle shaft dowel holes	Replace the axle shaft. Refer to Rear Axle Shaft Replacement or to Rear Axle Shaft and/or Gasket Replacement .
Worn hub studs	Replace the wheel studs. Refer to Wheel Stud Replacement .
Bent axle shaft	Replace the axle shaft. Refer to Rear Axle Shaft Replacement or Rear Axle Shaft and/or Gasket Replacement .