Workbook, Heavy Duty Truck Systems, 6E
Chapter Twenty-One – Answer Key
1. Which of the following terms best describes the management system used on Allison
CEC transmissions?
2. Which of the following is the intended application of a TC10 ECAT?
3. In which TC10 gear ratios does converter input torque bypass the main gearbox module?
4. Technician A says that input torque to the main gearbox module in a TC10 is divided
between its twin countershafts. Technician B says that the main planetary in a TC10 is
located in the main gearbox. Who is correct?
5. What is Allison diagnostic software known as?
6. Technician A says that Allison input shaft rpm data can be viewed in the DOC StripChart
field. Technician B says that Allison output shaft rpm data can be viewed in the DOC
StripChart field. Who is correct?
7. What software is required to troubleshoot a CX31 transmission?
8. Technician A says using AT-1 synthetic fluid in a CX-31 transmission considerably
shortens service life. Technician B says that using TranSynd synthetic fluid in Allison
transmissions considerably extends service life. Who is correct?
9. What is the function of the torsional damper on a WT torque converter?
10. What is the term used by Allison to describe the subsystems that make up the WT
transmission?
11. How many gearbox modules are there in an Allison WT transmission?
12. Which of the following is classified by Allison as an input module?
13. Which of the following correctly describes the means used to control the retarder
solenoids?
14. Technician A says that a WT VIM has at least two relays, one of which signals the
reverse warning circuit. Technician B says that a WT VIM may contain up to six relays.
Who is correct?
15. Technician A says that the WT tailshaft sensor uses a 100-tooth reluctor wheel.
Technician B says that the J1939 data bus allows WT electronics to share the TPS signal
with the engine. Who is correct?
16. Technician A says that in a PWM signal, the percentage of on-off time in one cycle
determines how switching outcomes are managed. Technician B says that the cycle
frequency will determine how duty cycle is managed. Who is correct?
17. Which solenoids have to be energized when a WT transmission is in fourth gear?