2360 Boswell Road Chula Vista, CA 91914 Phone 619.216.1444 Fax 619.216.1474 E-Mail tech@explorerprocomp.com PRO COMP SUSPENSION Suspension Systems that Work! NOTE: Installation of inner fender relocation bracket kit (PN 90-6640B) is advised when installing 35” tires on a 2008 model. 6” Lift Kit - 51800/51800MX 2000 - 2008 Chevrolet/GMC 3/4 ton 4X4 This document contains very important information that includes warranty information and instructions for resolving problems you may encounter.
51800 Revised 7.21.2008 INSTALLATION INSTRUCTIONS IMPORTANT: GM has changed the under side of the upper control arms in some 2006 models. If this suspension kit is installed on a vehicle equipped with these open upper A-arms, the bump stops will not make contact with the underside of the upper A-arms. If your vehicle is equipped with open upper A-arms you will need to install the bump stop plates from pack 90-6481. This hardware pack must be purchased separately.
51800 Revised 7.21.
51800 Revised 7.21.2008 PART# DESCRIPTION 72-05000100512 1/2” NYLOCK NUT 73-05000030 1/2” SAE FLAT WASHER 90-2126 COMPRESSION STRUTS 90-1562 REAR CROSSMEMBER 90-6100 SWAY BAR END LINK KIT 90-2122 SWAY BAR EXTENSION 90-6065 HARDWARE PACK 1 90-1010 SWAY BAR FRONT MOUNT BRACKET 117300007 RETAINER WASHER 45359 BLACK HOURGLASS BUSHING 61150 SLEEVE, 5/8” x 1.
Introduction: 51800 Revised 7.21.2008 ♦ This installation requires a professional mechanic! ♦ We recommend that you have access to a GM service manual for your vehicle to assist in the disassembly and reassembly of your vehicle. It contains a wealth of detailed information. ♦ Prior to installation, carefully inspect the vehicle’s steering and driveline systems paying close attention to the tie rod ends, ball joints, wheel bearing preload, pitman and idler arm.
51800 Revised 7.21.2008 • WARNING: Be extremely careful when loading or unloading the torsion bars! There is a tremendous amount of stored energy in the bars. Keep your hands and body clear of the adjuster arm assembly and puller tool in case anything slips or breaks! Remember your safety glasses! • While we have listed the hardware that is to be kept and that to be discarded, it would be wise to keep all hardware until the installation is complete.
51800 Revised 7.21.2008 8. Remove the anti-sway bar links that connect the sway bar to the lower A-arm and remove the sway bar. Save the rubber bushings from the links. 9. Remove the shock absorber from the lower mount and remove the mount adapter from the lower Aarm. Save these bolts. 10. Remove the upper and lower A-arm pivot nuts. Save this hardware for reuse on reassembly. 11. Support the A-arm assembly and carefully remove the pivot bolts. Lower the assembly to the floor and set aside.
51800 Revised 7.21.2008 A1 B1 Front of vehicle Cut lines B Note: Cut this sheet metal straight down from the face of the frame A Note: Cut this sheet metal 3/4” from the edge of the slot to the edge of the frame. Both Front and Rear mounts Passenger side, Rear. A2 Note: Cut this sheet metal with a radius sufficient to clear the lower A-arm adjusted completely inward Driver side, Rear.
51800 Revised 7.21.2008 22. Using an angle grinder or equivalent, remove any remaining weld from these areas to achieve a smooth surface and to smooth the cut edges from step 21. 23. On the driver side lower A-arm pocket, carefully cut the rear section out using the weld in plate (PN 96-1505) and ILLUSTRATION 3 as a guide. 24. On the upper A-arm mount pockets, remove the existing alignment cam pins and grind them flush to the pocket surface. 25.
51800 Revised 7.21.2008 Installation Illustration 3c 1. Tack the weld in plate (PN 96-1505) to the back of the pocket. DO NOT finish welding until the front differential has been reinstalled to ensure there is adequate clearance between the differential and the frame. Drivers side. 2. One at a time, position the A-arm drops into their respective positions.
51800 Revised 7.21.2008 tighten the assembly enough so that the strut can be moved without much effort to complete step 6. 6. Attach the differential to the passenger side spacer bracket (PN 90-1545) as shown in ILLUSTRATION 5 with the supplied 9/16” X 1 3/4” bolts. The large diameter washers go onto the slotted cast iron flange as indicated in the illustration. At this point, leave the fasteners slightly loose until the torque strut is positioned and the main cross member is back in place.
51800 Revised 7.21.2008 arm pocket. 11. Remove the cross member for access, rotate the strut out of the way and drill the strut mount hole using a 9/16” drill bit. 12. Finish welding the weld in plate (PN 961505). Paint the welded areas to prevent rust. 13. Rotate the strut back into place and install the supplied 9/16” X 1 1/4” bolt through the strut and through the frame member. Leave all hardware loose until the completion of the cross member installation. 14. Reinstall the rear cross member.
51800 Revised 7.21.2008 Front of vehicle PN 90-2222 Note Hole Location: See Instruction # 16 AN Washers 1/2” X 3 3/4” Bolts PN 90-2180 OEM Hardware (Both Sides) PN 90-4036 Illustration 11 View From Rear.
51800 Revised 7.21.2008 2222) , and rod ends from the front cross member to the center link drop using the 1/2” X 3 3/4” bolts, spacers (PN 90-2180), and reducer cones (PN 90-4036) provided. Follow the assembly shown in ILLUSTRATION 11. Torque the new bolts according to the torque chart on page 21 and re-torque the steering box and idler arm bolts to Manufacturers specifications. THESE COMPONENTS MUST BE ASSEMBLED EXACTLY AS SHOWN!! 20.
51800 Revised 7.21.2008 5/8” X 5 1/2” Bolt PN 90-6170 5/8” X 4 1/2” Bolt PN 90-1581 Driver Side PN 90-1580 Passenger Side Illustration 16 Illustration 17 Passenger side. Passenger side. 21. If you are not installing the multi-shock kit (PN 90-51200), replace A– arm Drops the drops and fasten them to the truck frame using the supplied 1/2” bolts through the frame and the 9/16” X 1 1/4” bolts through the OEM upper A-arm mounts. Tighten all hardware to specifications.
51800 Revised 7.21.2008 25. Install the factory half shafts to the differential with the OEM bolts. Torque to factory specifications. 5/8” Nylock Nut Illustration 19 Passenger side. 26. Install the factory sway bar by flipping it upside down. Use the OEM mounts and bushings on the frame. Using Illustration 18, install the new sway bar links (PN 90-6100). Use the OEM stem bushings. Do not torque hardware until vehicle is on the ground. 1/2” X 2 3/4” Bolt 27.
51800 Revised 7.21.2008 the top, outside of the upper A-arms. See ILLUSTRATIONS 20 & 21. 32. Install the front caliper assemblies to each side of the vehicle. Install the ABS sensor wiring and secure them to the brake lines with zip-ties. Again, the harness must be routed to prevent breakage or chaffing. IMPORTANT: Move the A-arm assembly up and down to its limits several times to check for binding and to ensure that there are no interference or pinching problems with the brake lines and ABS wiring. 33.
51800 Revised 7.21.2008 same orientation that they were removed (i.e. left front to left front, right front to right front!). Reset the torsion bar preload bolts using the measurements previously taken. Front of vehicle 37. Assemble both ends of the compression struts as shown in ILLUSTRATIONS 24 & 27 using the bushings (PN 15-11148) and sleeves (PN 90-2109). PN 90-2126 PN 90-2109 PN 15-11148 38.
51800 Revised 7.21.2008 bolts, washers, and tab nuts. See ILLUSTRATIONS 24, 26, & 27. Rotate the struts back up and install the 1/2” X 4” bolts supplied. Repeat this procedure for the other side. Torque the compression strut hardware to specifications. 40. With the truck still on jack stands and the suspension hanging at full extension, cycle the steering from lock to lock to check that all components have clearance and operate freely. Pay very close attention to the ABS wiring and brake lines! 41.
51800 Revised 7.21.2008 existing hardware. 4. Remove parking brake cable bracket from rear frame rail. Attach the supplied parking brake drop bracket (PN 90-1083) to the stock bracket hole location then using the 5/16” hardware provided attach the stock bracket to the new drop bracket . 5. Support the differential housing one side at a time. Remove the “U” bolts from that end and discard. Carefully lower the differential away from the OEM springs.
51800 Revised 7.21.2008 90-1817 Illustration 30 Driver side.
Notice to Owner operator, Dealer and Installer: Vehicles that have been enhanced for off-road performance often have unique handling characteristics due to the higher center of gravity and larger tires. This vehicle may handle, react and stop differently than many passenger cars or unmodified vehicles, both on and off–road. You must drive your vehicle safely! Extreme care should always be taken to prevent vehicle rollover or loss of control, which can result in serious injury or even death.
