HDD 203W - Heavy Duty Diesel Drivetrains

Credits: 4

     A.          Identify causes of clutch noise, binding, slippage, pulsation, vibration, grabbing, dragging, and chatter problems; determine needed action.

     B.          Inspect and adjust clutch linkage, cables, levers, brackets, bushings, pivots, springs, and clutch safety switch (includes push and pull-type
                  assemblies); check pedal height and travel; perform needed action.

     C.          Inspect, adjust, repair, and replace hydraulic clutch slave and master cylinders, lines, and hoses; bleed system.

     D.          Inspect, adjust, lubricate, or replace release (throw-out) bearing, sleeve, bushings, springs, housing, levers, release fork, fork pads, rollers,
                  shafts, and seals.

     E.          Inspect, adjust, and replace single-disc clutch pressure plate and clutch disc.

     F.           Inspect, adjust, and replace two-plate clutch pressure plate, clutch discs, intermediate plate, and drive pins/lugs.

     G.          Inspect and/or replace clutch brake assembly; inspect input shaft and bearing retainer; perform needed action.

     H.          Inspect, adjust, and replace self-adjusting/continuous-adjusting clutch mechanisms.

     I.            Inspect and replace pilot bearing.

     J.           Remove and reinstall flywheel, inspect mounting area on crankshaft, rear main oil seal, and  measure crankshaft end play; determine
                   needed action.

     K.           Inspect flywheel, starter ring gear and measure flywheel face and pilot bore runout; determine needed action.

     L.           Inspect flywheel housing(s) to transmission housing/engine mating surface(s) and measure flywheel housing face and bore runout;
                   determine needed action.

2.    Complete NATEF tasks related to heavy duty diesel Transmissions as listed

     A.          Identify causes of transmission noise, shifting concerns, lockup, jumping- out-of-gear, overheating, and vibration problems; determine
                   needed action.

     B.          Inspect, test, repair, or replace air shift controls, lines, hoses, valves, regulators, filters, and cylinder assemblies.

     C.          Inspect and replace transmission mounts, insulators, and mounting bolts.

     D.          Inspect for leakage and replace transmission cover plates, gaskets, seals, and cap bolts; inspect seal surfaces and vents; repair as
                  needed.

     E.          Check transmission fluid level and condition; determine needed service; add proper type of lubricant.

     F.          Inspect, adjust, and replace transmission shift lever, cover, rails, forks, levers, bushings, sleeves, detents, interlocks, springs, and lock
                  bolts/safety wires.

     G.         Remove and reinstall transmission.

     H.          Inspect input shaft, gear, spacers, bearings, retainers, and slingers; determine needed action.

     I.            Inspect transmission oil filters, coolers and related components; replace as needed.

     J.           Inspect speedometer components; determine needed action.

     K.           Inspect and adjust power take-off (P.T.O.) assemblies, controls, and shafts; deermine needed action.

     L.            Inspect and test function of reverse light, neutral start, and warning device circuits; determine needed action.

     M.           Inspect and test transmission temperature gauge, wiring harnesses and sensor/sending unit; determine needed action.

     N.            Inspect and test operation of automated mechanical transmission and manual electronic shift controls, shift, range and splitter solenoids,
                     shift motors, indicators, speed and range sensors, electronic/transmission control units (ECU/TCU), neutral/in gear and reverse                
                     switches, and wiring harnesses; determine needed action.

     O.            Inspect and test operation of automated mechanical transmission electronic shift selectors, air and electrical switches, displays and
                     indicators, wiring harnesses, and air lines; determine needed action.

     P.             Use appropriate electronic service tool(s) and procedures to diagnose automated mechanical transmission problems; check and record
                     diagnostic codes, clear codes, and interpret digital multimeter (DMM) readings; determine needed action.

     Q.            Inspect and test operation of automatic transmission electronic shift controls, shift solenoids, shift motors, indicators, speed and range
                     sensors, electronic/transmission control units (ECU/TCU), neutral/in gear and reverse switches, and wiring harnesses.

     R.            Inspect and test operation of automatic transmission electronic shift selectors, switches, displays, indicators, and wiring harnesses.

     S.            Use appropriate electronic service tool(s) and procedures to diagnose automatic transmission problems; check and record diagnostic
                     codes, clear codes, and interpret digital multimeter (DMM) readings; determine needed action.

 3.    Complete NATEF tasks related to heavy duty diesel Driveshafts and Universal Joints as listed below.

     A.          Identify causes of driveshaft and universal joint noise and vibration problems; determine needed action.

     B.          Inspect, service, or replace driveshaft, slip joints, yokes, drive flanges, and universal joints,  driveshaft boots and seals, and retaining
                   hardware; check phasing of all shafts.

     C.          Inspect driveshaft center support bearings and mounts; determine needed action.

     D.          Measure driveline angles; determine needed action.

4.    Complete NATEF tasks related to heavy duty diesel Drive Axles as listed below.

     A.          Identify causes of drive axle(s) drive unit noise and overheating problems; determine needed action.

     B.          Check and repair fluid leaks; inspect and replace drive axle housing cover plates, gaskets sealants, vents, magnetic plugs, and seals.

     C.          Check drive axle fluid level and condition; determine needed service; add proper type of lubricant.

     D.          Remove and replace differential carrier assembly.

     E.          Inspect and replace differential case assembly including spider gears, cross shaft, side gears, thrust washers, case halves, and bearings.

     F.          Inspect and replace components of locking differential case assembly.

     G.         Inspect differential carrier housing and caps, side bearing bores, and pilot (spigot, pocket) bearing bore; determine needed action.

     H.         Measure ring gear runout; determine needed action.

     I.           Inspect and replace ring and drive pinion gears, spacers, sleeves, bearing cages, and bearings.

     J.           Measure and adjust drive pinion bearing preload.

     K.           Measure and adjust drive pinion depth.

     L.            Measure and adjust side bearing preload and ring gear backlash.

     M.           Check and interpret ring gear and pinion tooth contact pattern; determine needed action.

     N.          Inspect, adjust, or replace ring gear thrust block/screw.

     O.         Inspect power divider (inter-axle differential) assembly; determine needed action.

     P.          Inspect, adjust, repair, or replace air operated power divider (inter-axle differential) lockout assembly including diaphragms, seals, springs,
                   yokes, pins, lines, hoses, fittings, and controls.

     Q.         Inspect, repair, or replace drive axle lubrication system: pump, troughs, collectors, slingers, tubes, and filters.

     R.          Inspect and replace drive axle shafts.

     S.          Remove and replace wheel assembly; check rear wheel seal and axle flange gasket for leaks; perform needed action.

     T.          Identify causes of drive axle wheel bearing noise and check for damage; perform needed action.

     U.         Inspect and test drive axle temperature gauge, wiring harnesses, and sending unit/sensor; determine needed action.

     V.          Clean, inspect, lubricate and replace wheel bearings; replace seals and wear rings; inspect and replace retaining hardware; adjust drive
                  axle wheel bearings. Verify end play with dial indicator method.