HEXA

REAR AXLE 10 13.2 GENERAL SYMPTOMS AND DIAGNOSIS Most drive axle problems fall into the categories of noise, vibration, leaks and failure to transmit power. Problem diagnosis normally beings with the customer’s complaint, which should include an exact description of the type of noise or Vibration and when it occurs. This is followed up by a road test over various types of road surfaces through the speed where the complaint occurs. It should be remembered that some sound will appear to come from locations other than the real source of the problem. Sound in drive shaft, exhaust system and body floor pan can do this, making it more difficult to locate the problem source. CONDITION POSSIBLE CAUSES Noise in all driving modes Road and tires, wheel bearings. Noise changes with type of road surface Road and tires. Noise tone lowers with vehicle speed Tires. Noise louder on turn Differential pinion and side gears, axle wheel bearings. Noise in one or more driving modes Ring and pinion gears. Clunk on change of speed or direction of power flow Worn differential shaft or thrust washers; worn U- joints. Wheel noise Wheel loose, faulty or bad wheel bearing. Vibration Damaged drive shaft, missing drive shaft balance weight, worn or out-of-balance wheels lug nuts, worn U- joint, loose spring U- bolts, loose / broken spring, damage axle shaft bearing, loose pinion gear nut, excessive pinion yoke run out, bent axle shaft. Differential gears scored Insufficient lubrication, improper grade of lubricant, lubricant contamination, excessive spinning of wheel. Loss of lubricant Lubricant level too high, worn axle shaft seals, cracked differential housing, worn drive pinion gear shaft seal, scored and worn yoke, axle cover not properly sealed, plugged vent or vent tube. Axle overheating Lubricant level too low, incorrect grade of lubricant, contaminated lubricant, bearing preload too high, excessive gear wear, insufficient ring gear backlash. Gear teeth broke. Overloading, erratic clutch operation, wheel pinning,