Special Tools
CH-39570 Chassis Ear
Equivalent regional tools: Special Tools
Condition
Action
Verify the customer complaint
Test the vehicle on a shop hoist or road test. Compare against normal operation of affected systems. It may be necessary to compare to a like vehicle to determine if an issue is present. Note: For vehicles equipped with air suspension, under normal operation some automated features may deplete air reservoir and cause the compressor to start resulting in a noise that may be initially unrecognizable to the customer. Note: If symptom exists related to but not included in the customer complaint, refer to appropriate symptom chart. Front Suspension Front Suspension Description and Operation Rear Suspension Rear Suspension Description and Operation Suspension General Diagnosis Noise Diagnosis - Front Suspension Noise Diagnosis - Rear Suspension Suspension Bottoms Suspension Strut and Shock Absorber Testing - On Vehicle
Noise changes with vehicle speed. Typical examples include rub, chirp, scrape, whine, or squeal.
Attach CH-39570 Chassis Ear nearest the estimated noise origin, check, adjust, and repeat until area of noise source is captured. Check tire pressure, adjust, or repair as necessary. Inspect tires for signs of excessive/abnormal/uneven wear, repair or replace components as necessary and tighten to correct specification. Inspect wheels and wheel trim for signs of excessive brake dust or dirt buildup and perform brake inspection as necessary. Inspect the wheel nuts for looseness and signs of rubbing/wear at the wheel-to-nut mating surfaces, repair or replace components as necessary and tighten to correct specification. Inspect wheel bearings for looseness, conduct wheel bearing diagnosis if necessary. Inspect rotational driveline component mating surfaces for signs of rubbing/abnormal wear indicating interference, repair or replace as necessary and tighten to correct specification.
Condition
Action
Inspect areas surrounding rotational assemblies such as wheels, tires, or axles for loose/suspended objects such as labels, conduit, or harnesses that could make contact during vehicle operation. Disc Brakes Fastener Specifications Front Drive Axle Fastener Specifications Front Drive Axle Noises Noisy When Coasting Hydraulic Brakes Brake System Noise Propeller Shaft Fastener Specifications Knock or Clunk Noise Ping, Snap, or Click Noise Scraping Noise Squeak Noise Universal Joint Noise Rear Drive Axle Constant Noise Fastener Specifications Noisy When Coasting Suspension General Diagnosis Suspension Strut and Shock Absorber Testing - On Vehicle Wheel Bearings Diagnosis Tires and Wheels Fastener Specifications Wheel Drive Shafts Fastener Specifications Symptoms - Wheel Drive Shafts
Noise changes with vehicle jounce, tilt, or cornering. Typical examples include rub, thud, scrape, rattle or squeak.
Attach CH-39570 Chassis Ear nearest the estimated noise origin, check, adjust, and repeat until area of noise source is captured. Perform Suspension Strut and Shock Absorber Test at corner nearest noise source. Inspect fasteners and bushings in area of noise for signs of wear/ looseness/damage, repair or replace subject fastener/component as necessary and tighten to correct specification. Inspect are of noise any loose or damaged heat shields, repair or replace as necessary and tighten to correct specification.
Condition
Action
Inspect wheels and wheel trim for signs of excessive brake dust
or dirt buildup and perform brake inspection as necessary.
Inspect the wheel nuts for looseness and signs of rubbing/wear at
the wheel-to-nut mating surfaces, repair or replace components
as necessary and tighten to correct specification.
Inspect wheel bearings for looseness, conduct wheel bearing
diagnosis if necessary.
Perform Trim Height Inspection, repair as necessary.
Inspect individual shock/strut in area of noise for signs of
external damage or looseness, repair or replace component as
necessary and tighten to correct specification.
Inspect each shocks/strut individually for signs of fluid leakage,
replace subject damper as necessary and tighten to correct
specification. Suspension Related Leaks