Bar Pin Alignment - ProGear Hendrickson HN FR Series Service Manual

SERVICE HINT
17730-285
Pro Gear and Transmission • 906 W. Gore St. Orlando, FL 32805 • 1 (877) 776-4600 / (407) 872-1901 • parts@eprogear.com
11. Using a trammel bar, measure the distance from the spindle center of the front drive axle to
the spindle center of the rear drive axle on both sides of the vehicle; see Figure 7-1, C and D.
12. Calculate the difference between measurements C and D.
a. If the measurements are within the vehicle manufacturer's specifications, then the rear
drive axle alignment is acceptable.
b. If alignment of the rear drive axle IS NOT within the vehicle manufacturer's specifica-
tions, then the alignment of this axle MUST be corrected. Correct the alignment of this
axle by following the bar pin alignment instructions.
13. Recheck measurements to confirm adjustments. Repeat Steps 9 through 12 until the cor-
rect alignment is achieved.
14. When all drive axle alignments are within the vehicle manufacturer's specifications then
the alignment procedure is complete.

BAR PIN ALIGNMENT

The alignment feature consists of
specially designed, tightly tolerance
steel shims which fill the ⁄ " (9.5 mm)
3
8
total gap between the bushing's bar
pin and the axle bracket legs. The gap
must be filled by placing the shims on
the bushing assembly in one of the
positions shown in Figure 7-2 or 7-3.
Hendrickson has three shim designs
options for alignment, part number
50130-000 (provided), 50131-000
and 57026-000, see Figure 7-5.
A BAR PIN SHIM MUST BE INSTALLED AT
EACH BOLT LOCATION. THE SAME PART
NUMBER SHIM IN THE SAME ORIENTATION
MUST BE USED AT BOTH BOLT LOCATIONS
ON ANY ONE END BUSHING. DO NOT
INSTALL OR STACK MORE THAN ONE SHIM
AT EACH BOLT LOCATION. USE GENUINE
HENDRICKSON BAR PIN SHIMS, DO NOT
USE STANDARD WASHERS. FAILURE TO FOLLOW THESE WARNINGS MAY RESULT IN IMPROPER VEHICLE
ALIGNMENT, FRACTURE OF THE AXLE BRACKET OR BAR PIN WHICH COULD RESULT IN THE LOSS OF
VEHICLE CONTROL AND POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE.
ALIGNMENT ADJUSTMENT
If alignment of the drive axles is required, as determined by an alignment inspection procedure,
the following steps will need to be performed.
1. Determine direction of axle thrust angle. Figure 7-4 illustrates the forward drive axle with a
thrust angle to the left (-negative thrust).
Axle movement is in the same direction as the increased shim thickness, see Figure 7-3.
FIGURE 7-2
Axle Bracket
Supplied by vehicle
manufacturer
1" Bolt
Tightening Torque
500-650 ft. lbs.
1" Washer
Bar Pin
Bar Pin
Alignment
Shim
19
HN ® FR Series
1" Locknut
Tightening Torque
450-600 ft. lbs.
Alignment & Adjustments