(3) Move the truck. Measure and mark lines between
placed. Welded connections between rails and crossmem-
all marks, diagonally and parallel to the siderails. Corre-
bers are not recommended.
sponding measurements should not differ by more than a
a. Straightening. Limit straightening to parts not severely
quarter of an inch.
bent. Replace the part if its original shape is not easily
(4) Measure the width at the front and rear marks.
Divide the distance in half to determine the center points.
b. Welding (4X2 Models Only).
(5) Stretch a chalk line between points 1 and 2 in
(6) Measure the distances from the centerline to the
Never weld the frame of a 4X4 truck, since
diagonal intersections (points A, B, C, D, E, and F in figure
it may be used off the road.
9-3). This will tell you
if the frame
to the right
left. The distance should not exceed one-eighth inch per
Use electric welding equipment when welding to the
100 inches of frame.
siderails or crossmembers. This retains heat in a small
area, limiting the change of hardness of the metal. Inspect
(7) Any point on one siderail should be within one-
a damaged frame for cracks. Repair any cracks as follows:
eighth inch above or below the corresponding point on the
(1) Stop-drill at the end point of the crack with a
(8) Overall width of the frame should not vary more
than one-eighth inch.
(2) V-groove the crack to allow good weld
if required (para-
graph 9-3), and repeat the procedure.
(3) Weld up the crack.
b. Vertical or Sideview. To determine the frame twist or
(4) Grind the surface smooth if reinforcement is to be
the degree that the siderails are not parallel to one another,
proceed as follows:
c. Use of Fasteners.
(1) Measure vertical dimensions from a level floor to
(1) Use grade five bolts in repairing frames or adding
the corresponding points on the left and right siderails.
(2) Plot the dimensions to scale vertically or horizon-
(2) When substituting a bolt for a rivet, ream the
tally on a sheet of paper. Connect the points for each side-
hole and use the next larger size bolt.
member separately. The graph will show the relative posi-
(3) Use coned washers instead of the split-lock type.
tion of the sidemembers.
(4) Proper torque
(3) Select points on the siderail at the rear frame
crossmembers. Any one of these points on one siderail must
not be more than one-eighth inch above or below the cor-
d. Reinforcing. Make reinforcements from the channel
responding point on the other siderail.
angle or flat stock of a common carbon steel. The reinforce-
ment must be about the same thickness as the part being re-
9-3. Servicing the Frame.
paired. The reinforcing channel must have flanges shorter
Straighten bent or twisted frames by applying heat. Dam-
than the sidemember flanges; this guards against welding
aged parts can be repaired by straightening, or can be re-
along the edge of the rail flange. Otherwise, longitudinal
welds are acceptable. Avoid complete transverse welds.