ASE T3 Drive Train (Medium/Heavy Truck) case studies
ASE T3 Drive Train (Medium/Heavy Truck) · Put your knowledge to work in context.
ASE T3, Drive Train, is the medium/heavy truck certification test that covers the hardware that carries engine torque from the flywheel to the wheels of a commercial vehicle. It is written for working technicians - fleet shop hands, dealership driveline and axle specialists, and independent heavy-truck mechanics - who already diagnose and repair clutches, gearboxes, driveshafts, rear axles and power take-off systems on the job, and who want third-party proof of that skill for employers, insurers, or their own career plan. The ASE T3 Drive Train (Medium/Heavy Truck) case studies are 5 cases and about 3,351 words.
1Clutch Drag and Clutch Brake on a Pull-Type 15.5-Inch Clutch
A 2018 Class 8 tractor with a Cummins X15 and a 10-speed manual transmission came in with 1.1 million km. The clutch is a 15.5-inch pull-type unit with hydraulic release and an integral clutch brake.
701 words, about 4 min2Limp-Home in Third: Automatic Transmission Diagnosis on a Refuse Truck
A 2020 rear-loader refuse truck with an Allison 4500 RDS 6-speed automatic has 78,000 miles. The transmission uses a push-button range selector and drives a hydraulic packer pump through a PTO.
682 words, about 3 min3Driveline Vibration After Center Bearing Replacement
A 2017 Class 8 day cab tractor has a 3.90 rear axle ratio and 11R22.5 tires with a measured 512 rev/mile. After a center-support bearing replacement, the two-piece driveshaft was reinstalled and the center bearing was shimmed down 0.25 in to clear a new exhaust pipe.
645 words, about 3 min4Interaxle Binding After a Single Tire Replacement
A 2019 6x4 tandem tractor with a 3.55 ratio and 11R22.5 tires has an interaxle differential lock. After a blowout, one drive tire on the forward rear axle was replaced.
678 words, about 3 min5PTO and Hydraulic Overheat on a Dump Truck
A 2016 tandem-axle dump truck has a 13-speed manual, a gear-driven PTO with a 1.25:1 overdrive ratio, and a 30 gpm hydraulic pump rated at 1,000 rpm. The system raises the bed with a 6-inch cylinder through a 2,500 psi relief valve.
645 words, about 3 min