| AXLE
TROUBLESHOOTING |
|
|
ISSUE |
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
turns |
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 tires, loose wheel lug nuts, worn
U-joints, loose spring U-bolts, loose/broken
spring, damaged axle shaft bearings, 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
tires |
|
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 broken |
Overloading, erratic
clutch operation, wheel spinning, improper
adjustment |
|
Axle gear noise |
Insufficient
lubricant, incorrect backlash, improper tooth
contact, worn/damaged gears |
|
Axle noise |
Insufficient
lubricant, improper ring gear and drive pinion
gear adjustment, unmatched ring gear and drive
pinion gear, worn teeth on ring gear or drive
pinion gear, loose drive pinion gear shaft
bearings, loose differential bearings,
misaligned ring and pinion gear, loose
differential bearing cap screws, worn bearings |
|
Limited slip
differential |
The most common
problem is a "chatter" noise when turning
corners. The probable cause is incorrect or
contaminated lubricant or lack of friction
modifier additive in the lubricant, worn or
damaged plates and discs, plates and discs
improperly assembled |
|
|
| AXLE
TERMINOLOGY |
|
AXLE SHAFT
SEMI-FLOATING - Shaft that carries vehicle
load and transmits torque.
|
|
BACKLASH -
The amount of clearance or play between two meshed
gears.
|
|
BANJO-AXLE DESIGN
- An axle assembly with a final drive assembly that
assembles into the housing and is bolted into place.
|
|
BEARING CAP
- The portion of the axle housing that is bolted in
place to secure the differential bearings and
differential assembly.
|
|
BEARING CONE
- The inner race of a tapered roller bearing.
|
|
BEARING CUP
- The outer race of a bearing assembly.
|
|
CARRIER -
The casting center section of a drive axle that
contains the differential assembly, ring gear,
pinion gear and support bearings.
|
|
CENTER SECTION
- The carrier portion of a drive axle.
|
|
COAST - A load condition in which the
vehicle is driving the engine, as during deceleration. |
|
DECELERATE -
To reduce speed.
|
|
DIFFERENTIAL
- A gear arrangement that allows the drive wheels to
be driven at different speeds and divides the input
torque of one shaft between two output shafts.
|
|
DRIVE - A load condition in which the
engine is applying power to the wheels. |
|
DRIVE GEARS
- A large gear that meshes with a smaller gear. Also
known as a Crown Gear.
|
|
END YOKE -
Yoke-shaped forging that forms part of the universal
joint connection the drive shaft to the transmission
or axle.
|
|
EXTREME PRESSURE
(EP) LUBRICANT - A lubricant designed to
stay in place and keep the gears from touching when
under extremely high pressure (e.g., heavy torque
loads).
|
|
SALISBURY AXLE
DESIGN - Axle assembly with final drive
components assembled into one piece housing.
|
|
SHIM - A thin spacer used to adjust
preloads and ring gear to pinion gear backlash may also
be used for controlling pinion gear positions. |
|
FLOAT - A
load condition where two parts are turning at the
same speed with no driving force between them.
|
|
FLANGE YOKE
- Same as an end yoke except circular in design.
|
|
FULL-FLOATING AXLE
- Axle shaft which transmits torque only and carries
no vehicle load.
|
|
GEAR - A
wheel with teeth that transmits power or motion to
another gear.
|
|
GEAR RATIO -
The ratio in the number of teeth on the driving and
driven gears; it is calculated by dividing the
number of teeth on the driven gear by the number of
teeth on the driving gear.
|
|
HEEL - The
outer end of a bevel or hypoid ring gear tooth.
|
|
HOUSING -
Portion of the axle assembly that consists of the
carrier and axle tubes.
|
|
HYPOID GEAR
- A special form of bevel gear that positions the
gear axis on non-intersecting planes and is commonly
used in drive axles.
|
|
LIMITED SLIP
DIFFERENTIAL - Differential in which the
difference in rotational speed or torque between two
output shafts is mechanically limited to prevent
wheel spin on difficult terrain.
|
|
NEWTON METER (N.M.)
- The metric measurement of torque.
|
|
PINION GEAR
- A small gear that meshes with a larger gear.
|
|
PITCH LINE -
The effective diameter of a gear; midpoint of the
gear tooth.
|
|
PRELOAD - A
load placed on parts during assembly to maintain
critical clearances and adjustments when operating
loads are applied.
|
|
R.T.V. - A
formed-in-place gasket material; a rubber like
compound that vulcanizes at room temperature.
|
|
TOE - The
inner end of a bevel or hypoid ring gear tooth.
|
|
TORQUE - A
turning or twisting force that is normally measured
in pound-feet or Newton meters.
|
|
VISCOSITY -
The resistance to flow of a fluid.
|
|
