7. LONG WHEELBASE TRUCK
A highly rigid sub-frame should be used on long wheelbase trucks to
avoid deflection. Channel steel, lip channel steel and square pipe can be
utilized. Do not use a wooden sub-frame.
When a side gate center pillar is installed on a drop side gate body,
the pillar should be located ahead of the center of the rear wheels, by at
least 30 in (762 mm) to prevent rear overhang deflection (Fig.19).
[CHASSIS FRAME]
When drilling the chassis frame to mount a rear body or special equip-
ment, the following precautions must be taken to avoid serious damage to
the vehicle or reducing frame strength. Mounting should not cause stress
concentration in the frame such as may occur from improper location,
size or finishing of holes or by improper riveting.
1. DRILLING THE FRAME
When drilling the frame, use an ordinary twist drill. Do not use a torch
(Fig. 20).
All holes must be finished after drilling to help reducing the possibility
of stress concentration. Chamfer all holes for fitted bolts on both bolt head
and nut faces (Fig. 21).
C16