GMC 4000 Series Service Manual page 72

Before any body mounting is attempted, this
section should be studied carefully and the rec­
ommendations followed as closely as possible.
When mounting bodies, certain important pro­
cedures should be followed. Unless such practices
are followed, strains of load and chassis weave
may not be distributed correctly, causing damage
to body or frame.
IMPORTANT: Avoid drilling additional holes
in frame for mounting bolts. Use existing holes if
possible; if additional holes are necessary, close
unused holes by welding.
LONGITUDINAL SILL M O UNTING
If body is equipped with longitudinal sills,
observe following standard practices.
1. Wooden longitudinal sill should rest direct­
ly on top flange of chassis frame side rail. If pro­
jecting rivet heads prevent a solid bearing, coun­
1 Frame Side Rail
2 Longitudinal Sill
3 Spacer Block
G M C S E R V I C E M A N U A L
(lady MountitKfi
PLATFORM BODY MOUNTINGS
TO P V IEW
SID E VIEW
4 W ood Filler Block
5 Clip Plate
6 Metal Channel
7 Mounting Bolt
Figure 1— Typical B o d y M o u n tin g s
tersink longitudinal s ills just enough to clear rivet
heads.
IMPORTANT: Do not use spacers to raise sills
above rivet heads. If body longitudinal sill is of
metal, it will be necessary to use a one-piece full
length hardwood strip, with holes to clear rivet
heads between body s ill and frame rail. Wood strip
should be firmly fastened to body sill.
2. Sill should extend as close as possible to
back of cab without interfering with mounting or
movement of cab.
3. Make sure height of sill is sufficient to
prevent body from striking tires, or other parts
of chassis, with maximum spring deflection. Take
into consideration full load operation over ex­
tremely rough terrain.
4. Sill must rest squarely on frame flange and
not overhang outside of frame. If sill width does
not cover entire width of frame, install a spacer
block as shown in figures 1 and 2. Blocks should
EN D V IEW
8 Lock Nut
9 Nut
10 Cross Sill
Sec. 1
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