Home › CDL Practice Tests › Combination Vehicles Questions › Question 8
Why is a tug test alone not enough to confirm a good coupling?
- A.A tug test is only valid at highway speed
- B.You must also get out and visually check that the locking jaws are closed around the kingpin
- C.The jaws can only be checked while driving
- D.Visual checks are optional if the test feels solid
Correct answer
B. You must also get out and visually check that the locking jaws are closed around the kingpin
Why
A partial or false lock can sometimes hold a gentle tug but fail later. Seeing the jaws closed around the shank, not the head, of the kingpin is the confirmation the test cannot give.
Manual topic: Combination Vehicles - Coupling · From the Combination Vehicles practice bank (CV-008).