Suspension - Front (Leaf) Chevrolet Forward Control P30

DESCRIPTION

Leaf spring assembly attaches to front axle with "U" bolts. A kingpin is used to attach the steering knuckle to the front axle. The kingpin is part of bearing cap and rides in a tapered roller bearing. (Scheme 11)

Note. All figures are Courtesy of General Motors Corp.

Exploded View Of Front Suspension (Commercial Van - C35 Pickup Similar). Scheme 11

WHEEL ALIGNMENT SPECIFICATIONS & PROCEDURES

On Commercial Van, caster and camber are designed into front axle assembly and are nonadjustable. Toe-in can be adjusted. See ALIGNMENT SPECIFICATIONS/PROCEDURES article in the WHEEL ALIGNMENT Section.

FRONT WHEEL BEARINGS

Raise and support vehicle. Remove bearing cap and cotter pin. To seat bearing, tighten adjusting nut to 12 ft. lbs. (16 N.m) while rotating wheel. Back off adjusting nut approximately one flat. Check rotor and hub end play. End play should be .0005-.0080" (.013-.203 mm). Install cotter pin and bearing cap. If hole in spindle and slot in adjusting nut do not line up, back off adjusting nut one additional flat.

Removal

Raise and support vehicle. Remove wheel assembly. Remove brake caliper and support aside. DO NOT allow caliper to hang by brake line. Remove bearing cap and cotter pin. (Scheme 11) Remove adjusting nut, washer, outer bearing and wheel hub/rotor assembly. Remove grease seal and inner bearing (if necessary). Using a brass drift, remove bearing races (if necessary).

Inspection

Wash all bearings in solvent and check for cracked bearing cages and worn, chipped or pitted rollers. Wash hub I.D. and inspect bearing races for cracks, scoring or looseness in hub. Replace components as needed.

Note. Always replace bearings and races as matched sets. Install NEW grease seal whenever wheel hub is disassembled. Before assembly, ensure all parts are thoroughly lubricated.

Installation

Install outer bearing race using Bearing Installer (J-29040 ). Install inner bearing race, using 3" (76.2 mm) diameter rod. DO NOT use a bar larger than specified as it may damage bearing seal seat. Pack wheel bearings with wheel bearing grease. To complete installation, reverse removal procedure. Adjust wheel bearings. See FRONT WHEEL BEARINGS under ADJUSTMENTS.

SPINDLE

Note. For spindle removal, see STEERING ARM, KNUCKLE & KINGPIN under REMOVAL & INSTALLATION.

1. Raise and support vehicle. Remove wheel assembly. Remove brake caliper and support aside. DO NOT allow caliper to hang by brake line. Remove wheel hub/rotor assembly. See «WHEEL HUB/ROTOR & BEARINGS»(/chevrolet/forward-control-p30/1985-1999/remont/suspension-front/#suspension-front-leaf) under REMOVAL & INSTALLATION.
2. Remove mounting bolts, nuts and washers. Remove anchor plate, splash shield and steering arm. (Scheme 11) Steering arm can hang by tie rod end. Remove upper and lower kingpin cap bolts, washers, brake line bracket, kingpin caps and gaskets from steering knuckle.
3. Remove lock pin nut and washer. Tap out lock pin. Using a drift, remove kingpin, spacers and bushings. Remove steering knuckle and spindle assembly. Remove dust seal, shim and thrust bearing. (Scheme 11)

1. Install NEW kingpin bushings. Ream bushings to 1.1804-1.1820" (29.982-30.023 mm). Lubricate thrust bearing. Install steering knuckle, thrust bearing, shim and dust seal. Lubricate kingpin.
2. Install kingpin and spacers. Install lock pin, washer and nut. Install gaskets, kingpin caps, brake line bracket, washers and bolts into steering knuckle. To complete installation, reverse removal procedure.
3. Tighten bolts and nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/forward-control-p30/1985-1999/remont/suspension-front/#suspension-front-leaf) table at end of article. Lower vehicle and check wheel alignment. See ALIGNMENT SPECIFICATIONS/PROCEDURES article in the WHEEL ALIGNMENT Section.

Removal & Installation

Raise and support vehicle. Remove wheel assembly. Remove upper shock-to-frame rail nuts and washers. (Scheme 11) Remove lower shock-to-leaf spring spacer nuts and washers. Separate shock from frame rail and leaf spring spacer and remove from vehicle. To install, reverse removal procedure. Tighten nuts to specifications. See TORQUE SPECIFICATIONS table at end of article.

1. Raise and support vehicle. Remove wheel assembly. Remove stabilizer link nuts and washers. Using Tie Rod Remover (J-6627-A ), disconnect stabilizer links from stabilizer bar end. Remove nuts, washers and bracket bolts attaching stabilizer brackets and bushings to frame rail. (Scheme 12)
2. Remove stabilizer bar from vehicle. Remove bushings from stabilizer bar. Remove stabilizer link nuts, upper and lower retainers and upper and lower bushings from front axle. Inspect rubber bushings for excessive wear or deterioration. Check bar and links for damage. Replace as necessary.

1. Install upper retainer and bushing onto stabilizer link. Install stabilizer link into front axle. Install lower bushing, retainer and link nut. Tighten link nut until distance between retainers measures 2.08" (52.8 mm). (Scheme 12)
2. Place stabilizer bar and bushings in position on frame and install brackets over bushings. Ensure brackets are positioned properly over bushings. Install bracket bolts, washers and nuts. Connect stabilizer bar to stabilizer link. Install washers and nuts.
3. To complete installation, reverse removal procedure. Tighten all bolts and nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/forward-control-p30/1985-1999/remont/suspension-front/#suspension-front-leaf) at end of article.

Scheme 12

1. Raise and support vehicle. Place adjustable jack stand under axle. Lift axle until all tension is relieved from leaf spring assembly. Remove wheel assembly. Remove shock absorber. See «SHOCK ABSORBER»(/chevrolet/forward-control-p30/1985-1999/remont/suspension-front/#suspension-front-leaf) under REMOVAL & INSTALLATION.
2. Remove stabilizer link nut and washer. (Scheme 12) Using Tie Rod Remover (J-6627-A ), disconnect stabilizer link from stabilizer bar end. Remove stabilizer link nuts, upper and lower retainers and upper and lower bushings from front axle. Remove "U" bolt-to-front axle nuts and washers. Remove "U" bolts, "U" bolt spacer and leaf spring spacer.
3. Separate leaf spring from front axle. On Commercial Van, remove shackle-to-leaf spring bolt, nut and washers. (Scheme 13) On C35 Pickup, remove rear hanger-to-leaf spring bolt, nut and washer. Remove front hanger-to-leaf spring bolt, nut and washers. Pull leaf spring back and out to remove from vehicle.

1. To install, reverse removal procedure. Position leaf spring with double wrapped end toward front of vehicle. Tighten "U" bolt nuts in a diagonal sequence. (Scheme 13) Tighten stabilizer link nut until distance between retainers measures 2.08" (52.8 mm). (Scheme 12)
2. Tighten bolts and nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/forward-control-p30/1985-1999/remont/suspension-front/#suspension-front-leaf) table at end of article. Lower vehicle and check wheel alignment. See ALIGNMENT SPECIFICATIONS/PROCEDURES article in the WHEEL ALIGNMENT Section.

Removing & Installing Leaf Spring (Commercial Van - C35 Pickup Similar). Scheme 13

1. Raise and support vehicle. Place adjustable jack stand under axle. Lift axle until all tension is relieved from leaf spring assembly. Remove wheel assembly. Remove steering arm, knuckle and spindle. See «STEERING ARM, KNUCKLE & KINGPIN»(/chevrolet/forward-control-p30/1985-1999/remont/suspension-front/#suspension-front-leaf) under REMOVAL & INSTALLATION.
2. Remove lower shock-to-leaf spring spacer nuts and washers. Separate shock from leaf spring spacer. Remove stabilizer link nut and washer. (Scheme 12) Using Tie Rod Remover (J-6627-A ), disconnect stabilizer link from stabilizer bar end. Remove stabilizer link nuts, upper and lower retainers and upper and lower bushings from front axle.
3. Remove "U" bolt-to-front axle nuts and washers. Remove "U" bolts, "U" bolt spacer and leaf spring spacer. (Scheme 13) Separate leaf spring from front axle. Remove steering dampener-to-front axle nut and washer. Separate steering dampener from front axle. Lower jack and remove front axle from vehicle.

1. To install, reverse removal procedure. Tighten "U" bolt nuts in a diagonal sequence. (Scheme 13) Tighten stabilizer link nut until distance between retainers measures 2.08" (52.8 mm). (Scheme 12)
2. Tighten bolts and nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/forward-control-p30/1985-1999/remont/suspension-front/#suspension-front-leaf) table at end of article. Lower vehicle and check wheel alignment. See ALIGNMENT SPECIFICATIONS/PROCEDURES article in the WHEEL ALIGNMENT Section.

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• FRONT WHEEL BEARINGS
• STEERING ARM, KNUCKLE & KINGPIN