Specifications

17730-248 29 Preventive Maintenance

AIRTEK

•

SOFTEK

for Blue Bird Buses

CLAMP GROUP RE-TORQUE INTERVAL

1. Clamp group locknuts must be torque to specification at preparation for delivery.

2. Clamp group locknuts must be re-torqued at 1,000 miles.

3. Thereafter follow the 6 month/ 25,000 mile inspection and annual re-torque interval.

4. Ensure that the clamp group is properly aligned and the hex bolts/U-bolts are seated in

the top pad, and the bottom axle wrap is centered on the top axle wrap, see Figure 7-8.

FIGURE 7-8

5. Check for the signs of component or bolt movement.

6. If signs of movement are present, disassemble the clamp group fasteners, check for

component wear or damage and replace as necessary, then install new clamp group

fasteners and repeat steps 1 through 5.

FIGURE 7-9

7. Tighten the clamp group locknuts evenly in 50 foot pounds increments

to 285-305 foot pounds torque in the proper pattern to achieve uni-

form bolt tension, see Figure 7-9.

TIRE INSPECTION

The leading causes of tire wear are the following, in order of importance:

1. Tire Pressure

2. Toe Setting

3. Thrust Angle

4. Camber

The following tire Inspection guidelines are based upon TMC (Technology & Maintenance

Council) recommended practices. Any issues regarding irregular tire wear where

Hendrickson is asked for assistance, will require tire and alignment maintenance records,

reference TMC’s literature numbers RP219A, RP230, or RP 642.

Tire wear is normally the best indicator of vehicle alignment condition. If tires are wearing

too rapidly or irregularly, alignment corrections may be needed. The tire wear patterns

described below can help isolate specific alignment problems.

SERVICE MANUAL

FRONT AXLE & SUSPENSION

APPENDIX