BRAKE SYSTEM
- incorrect brake adjustment
- air system
- timing vs. brake force analysis
- faulty
slack adjusters or S-cams
- glazed or contaminated linings (oil,
grease, or brake fluid)
- seized hydraulic wheel cylinders
- badly worn S-cam bushings
- faulty
air compressor
- worn
or faulty brake pedal
- faulty treadle valve
- pedal effort to apply brakes
- pedal
to brake timing
- air pressure to brake timing
- measure braking to each individual
wheel
- hot
spots on drums
- out of round drums
- sticky air valves
- blocked air lines
- improper
brake balance between axles
- matching
tractor and trailer brakes to eliminate jack-knifing
- damaged
air or hydraulic lines
and hoses
- leaking oil seals and worn
and damaged components
- broken
spring coils in park brake chamber
- worn brake linings or
drums
- incorrect
brake
lining-to-drum radius
- problems
due to driving habits
- stopping distances
STEERING
and SUSPENSION SYSTEMS
- worn tie rod end
- worn king pins
- worn spring pins,
shackles, and hangers
- worn bushings
- bad or loose shock absorbers
- loose
u-bolts
- air-bag integrity
FRAME
- loose bolts
- cracks in chassis and cross members
- loose
or
worn engine
and transmission
mounts
- loose or worn cab and sleeper mounts
and bushings
WEIGHT
- weigh vehicle
- weigh each wheel position to detect bent frame or component
- weigh each axle to check balance
OTHER
- loose wheel bearings
- high rolling
resistence
- problems in driveline detected through wheels resistance
to turn
- worn yokes, center bearings
- loose or
worn exhaust