Pre-Trip Inspection: Steering
10 questions in the bank cover this topic. Everything below is drawn from the sources those questions cite.
Sources: 49 CFR 396 Appendix A, 49 CFR 570.60
What you need to know
Free movement through the whole range, both ways.
Binding at one extreme usually means something is fouling, and you discover it mid-turn when you most need the lock.
Steering wheels shall turn freely through the limit of travel in both directions.
49 CFR 570.60
570.60(e) lists all of them.
Power steering fails gradually through leaks rather than suddenly, so the fluid level is the early warning and the belt is the thing that strands you.
The power steering system shall not have cracked, frayed or slipping belts, chafed or abrated hoses, show signs of leakage or have insufficient fluid in the reservoir.
49 CFR 570.60
A quarter inch.
Rotation is what the joint is for; movement in any other direction is wear, and it multiplies by the time it reaches the road wheel.
Any motion, other than rotational, between any linkage member and its attachment point of more than 1/4 inch.
49 CFR 396 Appendix A
All three are listed under the steering column.
A welded repair appears because heating the steel changes its properties, so a mended joint is weaker than the one it replaced.
Any absence or looseness of U-bolt(s) or positioning part(s).
Steering wheel not properly secured.
49 CFR 396 Appendix A
An obvious welded repair on steering components is a defect in its own right, separate from any crack.
The standard will not accept a mend where failure means losing steering.
Front Axle Beam and All Steering Components Other Than Steering Column. (1) Any crack(s). (2) Any obvious welded repair(s).
49 CFR 396 Appendix A
None at all.
The pitman arm is the single joint carrying every steering input from the box to the linkage, so any play there is play in all of it.
Pitman Arm. Any looseness of the pitman arm on the steering gear output shaft.
49 CFR 396 Appendix A
It is the single joint carrying every steering input out of the box, which is why no looseness at all is permitted there.
Pitman Arm. Any looseness of the pitman arm on the steering gear output shaft.
49 CFR 396 Appendix A
The drag link runs fore and aft from the pitman arm to the steering arm.
The tie rod is the one running across between the two wheels.
Any motion, other than rotational, between any linkage member and its attachment point of more than 1/4 inch.
49 CFR 396 Appendix A
The tie rod ties the two knuckles together so both wheels follow the same input.
Lose it and one wheel steers independently.
Any motion, other than rotational, between any linkage member and its attachment point of more than 1/4 inch.
49 CFR 396 Appendix A
Free play is how far the wheel turns before anything happens at the road wheels.
On a power-steering vehicle the engine must be running to measure it.
Lash or free play in the steering system shall not exceed the values shown in Table 2.
49 CFR 570.60
Check yourself
- What is required of your steering wheel through its full travel?
- What is a power steering defect?
- What is the maximum non-rotational movement at a steering linkage joint?
- What are the steering column conditions that put a vehicle out of service?
- What is the status of a steering component with a welded repair?
- What is the maximum looseness at the pitman arm?
- The part that takes the steering gear box output to the linkage is:
- The part connecting your pitman arm to the steering arm is:
- The part that keeps your two steering wheels turning together is:
- Where do you check steering free play?
Answers are in the practice test for this topic.