Drivetrains and Transmissions

How power travels from the engine or motor to the wheels and how drivetrains are diagnosed and repaired, followed through an apprentice's summer towing season at Ridgeline Auto Service in Denver: gear ratios and torque, clutches and dual-mass flywheels, manual transmissions and synchronizers, torque converters and planetary gear sets, electronic shift control and adaptive learning, automatic transmission fluid, service and diagnosis, CVTs, hybrid power-split and dual-clutch transmissions, driveshafts, U-joints and CV axles, differentials, transfer cases and all-wheel drive, and a capstone diagnosis of a shift complaint and a driveline vibration.

AUTO-310 12 lessons · 4 h 16 min ▶ Video lessons coming soon

Offered by HSM University · Automotive Service

This is the American version of this course. See the Canadian version.

What you'll learn

Explain what a drivetrain must do, identify the parts of front-wheel, rear-wheel, all-wheel and four-wheel-drive layouts, and calculate road speed from engine speed, overall ratio and tire size
Calculate gear ratios from tooth counts and for gears in series, and the torque and speed through a gear train, and explain ratio spread, gear steps and the effect of tire size on effective gearing
Explain how a clutch and its release system work, calculate clutch torque capacity, confirm clutch slip with data, and inspect and replace a clutch and dual-mass flywheel
Explain how manual transmissions and transaxles, synchronizers and shift mechanisms work, select the correct fluid, and diagnose grinding, jumping out of gear and noise
Explain how a torque converter multiplies torque and locks up, calculate planetary gear set ratios, and use a clutch application chart to identify a slipping element
Explain how a transmission control module chooses and makes shifts, interpret shift and converter clutch data, and perform adaptive relearns and software updates correctly
Diagnose automatic transmission complaints in a logical order, check and service fluid by the maker's procedure, and relate towing loads and temperature to fluid life and transmission damage
Explain how belt CVTs, power-split hybrid transaxles and dual-clutch transmissions work, and diagnose judder, slip and shudder with fluid, software and adaptation procedures
Explain driveshaft critical speed, U-joint speed fluctuation and its cancellation, and CV joint design, and diagnose and repair driveshafts, U-joints and half-shafts
Explain open, limited-slip and locking differentials and traction control, check ring and pinion setup, and diagnose differential noise and leaks
Explain part-time four-wheel drive, all-wheel drive and their couplings, diagnose engagement faults and driveline binding, and apply tire matching rules
Diagnose a shift complaint and a driveline vibration from interview to verified repair using gear ratios, fluid checks and vibration orders, and document each as complaint, cause and correction

Course content

12 lessons · 4 h 16 min total · final exam

1 How a drivetrain transmits power 22 min · quiz
2 Gears, ratios and torque multiplication 20 min · quiz
3 Clutches and dual-mass flywheels 21 min · quiz
4 Manual transmissions and transaxles 22 min · quiz
5 Automatic transmission fundamentals: torque converters and planetary gears 22 min · quiz
6 Electronic transmission control and adaptive learning 20 min · quiz
7 Automatic transmission service and diagnosis 22 min · quiz
8 CVTs and dual-clutch transmissions 22 min · quiz
9 Driveshafts, CV axles and U-joints 21 min · quiz
10 Differentials and final drives 21 min · quiz
11 Transfer cases, AWD and 4WD systems 21 min · quiz
12 Capstone: diagnosing a shift complaint and a driveline vibration 22 min · quiz
E Final exam 20 questions

Requirements

AUTO-120 Engine Fundamentals

Recommended background. You can start any course at any time.