To ensure balanced braking, how should slack adjusters on each side of an axle be?
- The same effective length ✓
- At different effective lengths to accommodate for road irregularities
- Alternately adjusted in length for alternate braking
- At least one inch apart in length
Answer: A. The same effective length
The slack adjusters at both ends of an axle need to match in effective length.
Why this is the answer
The handbook defines a slack adjuster’s effective length as the distance from the camshaft centre to the clevis pin, and notes that using a different hole changes that length. It says that for balanced braking, the slack adjusters across an axle must have matching effective lengths, so the pushrods are usually attached using the same hole. A steering axle with adjusters of unequal effective length is also listed as a defect.
Why the other answers are wrong
- B. At different effective lengths to accommodate for road irregularities — Setting them to different effective lengths would create the mismatch the handbook warns against, and the passages give no road-irregularity exception.
- C. Alternately adjusted in length for alternate braking — Alternating their lengths does not make them equal across the axle, so it does not meet the balanced-braking requirement.
- D. At least one inch apart in length — The passages do not set any one-inch separation rule; they call for matching effective length, not a particular distance between adjusters.
Remember it
Think of the two slack adjusters as a matched pair: same hole, same lever length, same braking effort.