Please enable JavaScript to view this page.

Heavy Duty Diesel Drivetrains

HDD 203W

Heavy Duty Diesel Drivetrains

HDD 203W

Course Description

Prerequisites: Prerequisites: HDD 202 and HDD 206 both with a grade of "C" (2.

0) or better. Corequisites: HDD 207, HDD 209W, and HDD 210. Introduces and practices the service of heavy duty diesel drivetrains. Practices NATEF tasks related to heavy duty diesel drivetrains. (60-30)

Outcomes and Objectives

Complete NATEF tasks related to heavy duty diesel Clutches as listed below.

Objectives:

  • Identify causes of clutch noise, binding, slippage, pulsation, vibration, grabbing, dragging, and chatter problems; determine needed action.
  • 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.
  • Inspect, adjust, repair, and replace hydraulic clutch slave and master cylinders, lines, and hoses; bleed system.
  • Inspect, adjust, lubricate, or replace release (throw-out) bearing, sleeve, bushings, springs, housing, levers, release fork, fork pads, rollers, shafts, and seals.
  • Inspect, adjust, and replace single-disc clutch pressure plate and clutch disc.
  • Inspect, adjust, and replace two-plate clutch pressure plate, clutch discs, intermediate plate, and drive pins/lugs.
  • Inspect and/or replace clutch brake assembly; inspect input shaft and bearing retainer; perform needed action.
  • Inspect, adjust, and replace self-adjusting/continuous-adjusting clutch mechanisms.
  • Inspect and replace pilot bearing.
  • Remove and reinstall flywheel, inspect mounting area on crankshaft, rear main oil seal, and measure crankshaft end play; determine needed action.
  • Inspect flywheel, starter ring gear and measure flywheel face and pilot bore runout; determine needed action.
  • Inspect flywheel housing(s) to transmission housing/engine mating surface(s) and measure flywheel housing face and bore runout; determine needed action.

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

Objectives:

  • Identify causes of transmission noise, shifting concerns, lockup, jumping- out-of-gear, overheating, and vibration problems; determine needed action.
  • Inspect, test, repair, or replace air shift controls, lines, hoses, valves, regulators, filters, and cylinder assemblies.
  • Inspect and replace transmission mounts, insulators, and mounting bolts.
  • Inspect for leakage and replace transmission cover plates, gaskets, seals, and cap bolts; inspect seal surfaces and vents; repair as needed.
  • Check transmission fluid level and condition; determine needed service; add proper type of lubricant.
  • Inspect, adjust, and replace transmission shift lever, cover, rails, forks, levers, bushings, sleeves, detents, interlocks, springs, and lock bolts/safety wires.
  • Remove and reinstall transmission.
  • Inspect input shaft, gear, spacers, bearings, retainers, and slingers; determine needed action.
  • Inspect transmission oil filters, coolers and related components; replace as needed.
  • Inspect speedometer components; determine needed action.
  • Inspect and adjust power take-off (P.T.O.) assemblies, controls, and shafts;deermine needed action.
  • Inspect and test function of reverse light, neutral start, and warning device circuits; determine needed action.
  • Inspect and test transmission temperature gauge, wiring harnesses and sensor/sending unit; determine needed action.
  • 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.
  • 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.
  • 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.
  • 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.
  • Inspect and test operation of automatic transmission electronic shift selectors, switches, displays, indicators, and wiring harnesses.
  • 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.

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

Objectives:

  • Identify causes of driveshaft and universal joint noise and vibration problems; determine needed action.
  • 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.
  • Inspect driveshaft center support bearings and mounts; determine needed action.
  • Measure driveline angles; determine needed action.

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

Objectives:

  • Identify causes of drive axle(s) drive unit noise and overheating problems; determine needed action.
  • Check and repair fluid leaks; inspect and replace drive axle housing cover plates, gaskets, sealants, vents, magnetic plugs, and seals.
  • Check drive axle fluid level and condition; determine needed service; add proper type of lubricant.
  • Remove and replace differential carrier assembly.
  • Inspect and replace differential case assembly including spider gears, cross shaft, side gears, thrust washers, case halves, and bearings.
  • Inspect and replace components of locking differential case assembly.
  • Inspect differential carrier housing and caps, side bearing bores, and pilot (spigot, pocket) bearing bore; determine needed action.
  • Measure ring gear runout; determine needed action.
  • Inspect and replace ring and drive pinion gears, spacers, sleeves, bearing cages, and bearings.
  • Measure and adjust drive pinion bearing preload.
  • Measure and adjust drive pinion depth.
  • Measure and adjust side bearing preload and ring gear backlash.
  • Check and interpret ring gear and pinion tooth contact pattern; determine needed action.
  • Inspect, adjust, or replace ring gear thrust block/screw.
  • Inspect power divider (inter-axle differential) assembly; determine needed action.
  • 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.
  • Inspect, repair, or replace drive axle lubrication system: pump, troughs, collectors, slingers, tubes, and filters.
  • Inspect and replace drive axle shafts.
  • Remove and replace wheel assembly; check rear wheel seal and axle flange gasket for leaks; perform needed action.
  • Identify causes of drive axle wheel bearing noise and check for damage; perform needed action.
  • Inspect and test drive axle temperature gauge, wiring harnesses, and sending unit/sensor; determine needed action.
  • 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.