Home › CDL Practice Tests › General Knowledge Questions › Question 378
What does a rising engine rpm with no increase in road speed during acceleration suggest?
- A.The engine has gained power
- B.The speedometer is rewarding you
- C.The clutch may be slipping, or the drive wheels may be spinning, either of which means power is not reaching the road normally
- D.This is normal in every gear
Correct answer
C. The clutch may be slipping, or the drive wheels may be spinning, either of which means power is not reaching the road normally
Why
The tachometer and speedometer should climb together in a fixed relationship for each gear. When they separate, something between the engine and the road is slipping, and continuing to pour on power only adds damage or digs the truck in.
Manual topic: Gauges - Diagnosis · From the General Knowledge practice bank (GK-378).