Paccar Kenworth T170 Hybrid 2011, Builder'S Manual

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Section 7
Frame Modifications
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Where possible, use existing bolt holes to attach the insert to the frame . Bolt holes must not be located closer to the frame
flanges than the present bolt pattern.
If the insert is placed in a section of the main frame where few bolts are located, additional bolts are required . Use the fol-
lowing guideline for locating additional bolt holes .
Changing Wheelbase
We do not recommend modifying the wheelbase. Occasionally, however, a chassis wheelbase will need to be reduced or
lengthened . When this needs to be done there are a few guidelines that should to be considered .
When changing the wheelbase, be sure to follow the driveline manufacturer’s recom-
mendations for driveline length or angle changes. Incorrectly modified drivelines can
fail prematurely due to excessive vibration and could cause personal injury and/or an
accident.
When changing the wheelbase, a continuous blank frame insert/outsert must be added
in the area of the new rear suspension mounting bolts. All new mounting holes must
pass through the original rail, rear suspension crossmembers and the insert/outsert.
Failure to do so could cause excessive stress in the original rail due to additional holes.
Before changing the wheelbase the driveline angles of the proposed wheelbase need to be examined to ensure that no
harmful vibrations are created. Consult the driveline manufacturer for appropriate recommendations.
Do not drill new holes any closer than 2 inches (50 mm) to existing holes. Frame drilling
affects the strength of the rails, and if not done properly can cause the frame rails to fail
and cause an accident.
Before the rear suspension is relocated, check the new location of the spring hanger brackets . The new holes for the
spring hanger brackets must not overlap existing holes and should not come any closer than 2 inches (50 mm) to existing
holes in the frame .
When relocating a suspension bracket, do not mount it on the extended (added) section
of a frame rail. The suspension loading could result in premature failure of the added
section splice. This could cause an accident. Use care when planning the wheelbase
so that the rear suspension bracket is always mounted on the original rail section. See
Figure 7–3.
If you are extending the wheelbase, you may also have to extend the frame length to accommodate a body. When you
reposition the rear suspension spring hangers, do not mount them on the added extended portion of the rail . The relocated
rear suspension bracket should be located on the original frame rails . See Figure 7–3 .
When reducing the wheelbase, we recommend that the suspension be moved forward and relocated on the original rail.
The rail behind the suspension can then be cut to achieve the desired frame cutoff. See Figure 7–3.
When changing the wheelbase & frame inserts are used, crossmembers require re-
placement and/or adjustment or in order to maintain the original frame rail spacing. Fail-
ure to do so could cause damage to rear suspension components & lead to an accident
When changing the wheelbase & frame outserts are used, the rear suspension requires
replacement to compensate for the original frame width caused by the outserts. Failure
to do so could cause damage to rear suspension components & lead to an accident.
When inserts longer than the minimum length are required, extra pairs of bolt holes shall be added, evenly spaced, result -
ing in bolt spacings of not less than 9 .8 inches (250mm) or more than 19 .7 inches (500mm) along the length of the insert,
as shown in Figure 7-2: Insert Detail, Variable Length .
WARNING:
WARNING:
WARNING:
WARNING:
WARNING:
WARNING: