Suspension and Slack Adjuster Inspection
Walk around the vehicle and visually inspect suspen- sion and slack adjuster components.
Inspect the following suspension components for signs of structural damage, cracks, or wear.
Inspect slack adjusters for signs of damage. See Fig. 21.1, Fig. 21.2, or Fig. 21.3.
Inspect slack adjuster boots, if equipped, for cuts or tears.
Inspect anchor straps, if equipped, for damage.
Wheel and Tire Inspection
Walk around the vehicle and visually inspect each wheel and tire assembly.
If the vehicle was originally equipped with wheel covers, ensure all wheel covers are present. In- spect wheel covers for damage or wear. Remove wheel covers from rear drive wheels, if equipped,prior to inspecting the tires and wheel components.
Inspect each tire for the following:
valve stem caps on every tire, screwed on finger-tight
bulges, cracks, cuts, and penetrations
oil contamination (petroleum derivatives will soften the rubber and destroy the tire)
tread depth—if tread is less than 4/32 inch (3 mm) on any front tire, or less than 2/32 inch (1.5 mm) on any rear tire, replace the tire
debris lodged between duel tire sets
Check tire inflation.
Examine each rim and wheel component. Check the wheel nuts or rim nuts for indications of looseness.
Inspect the outboard side of all wheel hubs and the hub oil seal area on the inboard side of each wheel for signs of oil leakage. If any oil is found on wheel and tire or brake components, remove the vehicle from service until the leak has been fixed.
Check that mud flaps are undamaged and hang 10 inches (25.4 cm) or less from the ground.
Saddle Tank Areas Inspection
Engine Compartment Inspection
Check the ground underneath the engine for fuel, oil, or coolant leaks.
Inspect the air intake system for leaks or damage.
Check the engine oil level.
Check the power steering reservoir fluid level.
Check the engine coolant level in the radiator surge tank.
Inspect visible engine wiring for damage or looseness. See Fig. 21.7.
Inspect visible frame rails for missing bolts, shiny areas, or rust streaks.
Push the reset button on the dash-mounted air intake restriction indicator, if equipped.
With the ignition switch in the OFF position, check the air-pressure warning system.
Check air governor cut-in and cut-out pressures.
Check air pressure build-up time.
Check air leakage in the system.
Check the air pressure reserve.
Check for fault codes.
Check the operation of all interior lights.
Check the operation of all exterior lights. See Fig. 21.8.
Inspect the seat belts and tether belts.
Adjust the rearview and down view mirrors as necessary.
Natural Gas Fuel System Inspection, If Equipped
Inspect fuel tanks for dents, scratches, gouges, or other signs of damage. Inspect the fuel lines and connections for leaks.
Check for the presence of all required decals present in the following locations:
Check for the presence of vent caps on pressure relief valves and devices. If any caps are miss- ing, have the fuel system inspected by a quali- fied technician.
Inspect all plumbing components, including the fuel shutoff valve(s), primary and secondary relief valves, and the LNG vapor shutoff and excess flow valves, if equipped, for signs of damage or leaks. See Fig. 21.9 or Fig. 21.10.
Source: MaintainX (Community Member)