1999 Chevrolet/GMC ½ ton RTII Undercarriage Mounting Instructions

The mounting procedure outlined below covers CHEVROLET/GMC (1999 and Newer) ½ ton 4 X 4 trucks. You will need to refer to the illustrations and familiarize yourself with each of the undercarriage components and their relative position to each other. Then proceed as follows:
1. Remove the existing tow hook bolts. Note: it may be necessary to remove the front bumper to remove the tow hooks. Position the PUSH BEAM SUPPORT PLATES (Ref. 62A and B, Fig. 1) to the front frame rails of the truck. Use the ½” – 13 x 6 bolts, the ½” – 13 hex head self locking nuts, the M12 x 40mm hex head bolts and the M12 lockwashers to bolt the PUSH BEAM SUPPORT PLATES in place (see Fig. 1). Drill the frame rail for the rear bolt position on the PUSH BEAM SUPPORT PLATES. Lower the PUSH BEAM SUPPORT PLATES and insert the J-NUTS. Replace the PUSH BEAM SUPPORT PLATES and secure using the hardware already mentioned and the 3/8-16 x 1-1/4 bolts and 3/8 flatwashers. Fasteners should only be finger tight.
2. Remove the existing plastic engine guard from the bottom front of the vehicle. Remove the four existing bolts holding the skid plate in place on the vehicle. Drill out the rear two existing positions in the vehicle crossmember as shown in Fig, 1, the bottom of the plastic engine guard and the front of the skid plate to 9/16”. Using the ½” – 13 x 1- ½” bolts and ½” – 13 hex head self locking nuts mount the ANGLE BRACKET (Ref. 75, Fig. 1) into place under the plastic engine guard and the skid plate. The plastic engine guard will need to be slotted for the ANGLE BRACKET. Bolts should only be finger tight. The plastic engine guard will be re-attached to the crossmember in step 5. Re-install the bumper if removed in step 1.
3. Bolt the PUSH BEAM (Ref. 62, Fig. 1) in place using the ½” – 13 x 1- ½” hex head bolts and self locking nuts provided. Fasteners should only be finger tight. Use the ½” – 13 x 1- ½” grade 8 bolts and the ½” – 13 grade 8 hex head self locking nuts to attach the ANGLE BRACKET to the PUSH BEAM with at least 2 bolts on each leg. The grade 8 hardware is coated with yellow zinc to distinguish them from other fasteners. NOTE: The proper height adjustment for the PUSH BEAM is approximately 12-1/2” for the 7’-6” V or 13-1/2” for the 8’-2” V and the 9’-2” V from the ground to the center of the PUSH BEAM MOUNTING ROD (see Fig. 2). Should the PUSH BEAM ASSEMBLY be mounted too high, the nose of the plow will tend to dig in while plowing. If the PUSH BEAM ASSEMBLY is mounted too low the wings of the plow will not lay flat against the ground. This will be most apparent when plowing in the scoop position.
4. With all undercarriage parts in place, securely fasten all mounting hardware. It is important that all fasteners be properly torqued (see Fig. 3) to assure a safe operating plow.
5. Align the lower holes of the plastic splash shield with the corresponding holes in the cross member and attach using the original hardware.

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