Alterations; Shear Plate Attachments; Trailer Towing - GMC G/H Van Manual

G/H V
6
an
(Section 2 — continued from previous page)

Alterations

If the wheelbase is modified, the alterer must take responsibility for compliance with affected motor vehicle safety and emission
standards and for warranty on items such as driveshafts, universal joints, center bearings and rear transmission tailshaft, transfer case
and transmission case fractures, output shaft bushings, bearings, brakes, fuel systems and any other related component failures.
Additionally, the customer must be alerted in the modifier's owner's manual that parts for the reworked area are not available through the
General Motors Service Parts System.

Shear Plate Attachments

Attachments of shear plates should be accomplished by using existing manufacturing holes already available.
When additional holes are required for shear plate attachment, they should be no larger than 20 mm (0.75 in.) in diameter. Holes are to
be drilled no closer than 63.5 mm (2.5 in.) apart. For holes drilled forward of the rear axle, centers are to be no closer than 63.5 mm (2.5
in.) from the top or bottom flanges and no closer than 89 mm (3.5 in.) from any suspension attachments. For frame holes drilled rearward
of the rear spring hanger bracket, hole centers are to be no closer than 51 mm (2.0 in.) from the top or bottom flange and no closer than
89 mm (3.5 in.) from suspension attachments.
Required large holes such as 20 mm (75 in.) diameter or larger, should be kept to a minimum required opening. Tubes should be welded
in place if holes in excess of 25 mm (1.0 in.) diameter are required.

Trailer Towing

The Incomplete Vehicle Document specifies that the CG location be within certain limits. The Body Builder must use all appropriate data.
Note to Body Builder/Final Stage Manufacturer: Failure to keep body and payload CG at least 26 inches forward of centerline of
rear axle will result in degradation of trailer towing capacity. Consult the Trailer Towing Guide to determine maximum tongue load for
your vehicle.
G/H Van 2007 – Rev. 2-07 G/H Van 2007 – Rev. 5-07