2-Wheel Drive Leaf Spring Front Suspension

Introduction

1997-98 F-Super Duty chassis/cab front suspension

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The F-Super Duty chassis/cab utilizes leaf springs attached to a solid, I-beam type front axle. The springs are mounted on the axle with U-bolts and attached to the frame side rails by a fixed bracket at the rear and moveable shackles at the front.

The F-Super Duty stripped chassis and motor home chassis utilize leaf springs attached to a solid, I-beam type front axle. The springs are mounted on the axle with U-bolts and attached to the frame side rails by a fixed bracket at the front and moveable shackles at the rear.

Chassis/cab models also utilize a tracking bar between the left side of the No.1 crossmember and the right side of the axle beam, inboard of the right spring pad.

Leaf Springs

REMOVAL & INSTALLATION

1997-98 F-Super Duty

Front spring and shock absorber installation for F-Super Duty chassis/cab

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Front spring and shock absorber installation for F-Super Duty stripped chassis or motor home chassis models

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Front stabilizer bar installation for F-Super Duty stripped chassis or motor home chassis

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  1. Raise and support the front end on jackstands with the tires still touching the ground.
  2. Using jacks, take up the weight of the axle, off the U-bolts.
  3. Disconnect the lower end of each shock absorber.
  4. Disconnect the spring from the front bracket or shackle.
  5. Disconnect the spring from the rear bracket or shackle.
  6. Remove the U-bolt nuts.
  7. Remove the U-bolts.
  8. Disconnect the jack bracket or stabilizer bar as necessary.
  9. Lower the axle slightly and remove the spring. Take note of the position of the spring spacer.

To install

  1. Position the spring on its seat on the axle and raise it to align the front of the spring with the bracket or shackle.
  2. Coat the bushing with silicone grease.
  3. Carefully guide the attaching bolt through the bracket or shackle, and the bushing.
  4. Install the nut and, depending on model or which bolts you removed, torque it to:
  1. In a similar fashion, attach the rear of the spring. The torques are:
  1. Position the spacer on the spring.
  2. Install the U-bolts. Install the jack bracket or stabilizer bar bracket on the forward U-bolt. Install the U-bolt nuts. Tighten the nuts, evenly and in gradual increments, in a crisscross fashion, to:
  1. Connect the shock absorbers. Tighten them to:

Shock Absorbers

1997-98 F-Super Duty chassis/cab front suspension

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Front spring and shock absorber installation for F-Super Duty chassis/cab

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Front spring and shock absorber installation for F-Super Duty stripped chassis or motor home chassis models

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TESTING

Refer to shock testing under 2 wheel drive coil spring suspension.

REMOVAL & INSTALLATION

  1. Remove the nut and bolt which retains the shock to the upper bracket.
  2. Remove the nut (chassis/cab) or nut and bolt (stripped chassis and motor home chassis) that retains the lower end of the shock at the spring.
  3. Installation is the reverse of removal. It's a good idea to lubricate the bushings with silicone grease prior to installation. Tighten the fasteners as follows:

Spindle

REMOVAL & INSTALLATION

1997-98 F-Super Duty

Front wheel spindle installation for F-Super Duty chassis/cab models

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Front wheel spindle installation for F-Super Duty stripped chassis or motor home chassis models

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Top spindle bushings replacement

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  1. Raise and support the front end on jackstands.
  2. Remove the wheels.
  3. Remove the caliper and suspend it out of the way (see Section 9).
  4. Remove the hub and rotor assembly (see Section 9).
  5. Remove the inner bearing and seal. Discard the seal.
  6. Remove the dust shield.
  7. Remove the cotter pin and nut, and, using a ball joint separator—the forcing screw type, not the fork type—disconnect the tie rod end from the spindle arm.
  8. On stripped chassis and motor home models, disconnect the drag link from the steering arm using a forcing type ball joint separator.
  9. Remove the nut and washer from the spindle bolt lock pin and remove the lock pin.
  10. Remove the upper and lower spindle pin plugs.
  11. Using a brass drift, drive out the spindle pin from the top and remove the spindle and thrust bearing.
  12. Remove the thrust bearing and seal.

To install:

  1. Clean the spindle pin bore and make sure it is free of corrosion, nicks or burrs. Light corrosion and other irregularities can be removed.
  2. Lightly coat the bore with lithium based grease meeting ESA-M1C75-B rating.
  3. Install a new spindle pin seal with the metal side facing up into the spindle. Gently press the seal into position being careful to avoid distorting it.
  4. Install a new thrust bearing with the lip flange facing downward. Press the bearing in until firmly seated against the surface of the spindle.
  5. Lightly coat the bushing surface with lithium based grease and place the spindle on the axle.
  6. Hold the spindle, with the thrust bearing in place, tightly against the axle, and measure the space between the axle and spindle at the top of the axle. Determine what thickness of shims is necessary to eliminate all play. Install the shims, available from the dealer.
  7. One end of the spindle pin is stamped with a T. Install the spindle pin, from the top, with the T at the top and the notch aligned with the lock pin hole.
  8. Install the lock pin with the threads forward and the wedge groove facing the spindle pin notch. Drive the lock pin in all the way and install the nut. Tighten the nut to 40-50 ft. lbs. (54-68 Nm).
  9. Install the spindle pin plugs. Tighten them to 35-50 ft. lbs. (47-68 Nm).
  10. Lubricate the spindle pin through the fittings until grease seeps past the upper seal and the thrust bearing slip joint at the bottom. If grease can't be forced past these points, the installation was probably done incorrectly and will have to be disassembled and re-assembled.
  11. Install the dust shield.
  12. Clean, pack and install the bearings. Install a new seal.
  13. Install the hub and rotor assembly.
  14. Install the caliper.
  15. Connect the tie rod end and, if necessary, the drag link. Tighten the nuts to 50-70 ft. lbs. (68-95 Nm). Always advance the nut to align the cotter pin holes. NEVER back them off! Always use new cotter pins!
  16. Install the wheels.

BRONZE SPINDLE BUSHING REPLACEMENT

Bearing seal installation on F-Super Duty

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Solid front axle spindle bushing installation

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Spindle bushing replacement tools for solid front axles

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Bottom spindle bushing replacement

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Reaming the bushings

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  1. Remove the spindle and secure it in a bench vise.
  2. The bushings have an inside diameter of 1.301-1.302 in. (33.05-33.07mm). Use the following tools or their equivalents:
  1. Remove and discard the seal from the upper bushing bore.
  2. Working on the upper bushing first, install the driver handle through the bottom bore. Position a new bushing on the T side of the tool. The bushing must be positioned so that the open end grooves will face outward when installed. Position the bushing and tool over the old bushing, insert the handle and drive out the old bushing while driving in the new bushing. Continue driving until the tool is fully seated. The new bushing should then be seated at the proper depth of 0.08 in. (2.03mm) minimum from the bottom of the upper spindle boss.
  3. Working on the bottom bushing, position the driver handle through the top bushing bore. Position a new bushing on the B side of the tool. The bushing must be positioned so that the open end grooves will face outward when installed. Position the bushing and tool over the old bushing, insert the handle and drive out the old bushing while driving in the new bushing. Continue driving until the tool is fully seated. The new bushing should then be seated at the proper depth of 0.13 in. (3.3mm) minimum from the top of the lower spindle boss.
  4. Ream the new bushings to 0.001-0.003 in. (0.025-0.076mm) larger than the diameter of the new spindle pin. Ream the top bushing first. Install the smaller diameter of the reamer through the top bore and into the bottom bore until the threads are in position is the top bushing. Ream the bushing until the threads exit the top bushing. Ream the bottom bushing. The larger diameter portion of the tool will act as a pilot in the top bushing to properly ream the bottom bushing.
  5. Remove the tool and thoroughly clean all metal shavings from the bushings and surrounding parts. Coat the bushings and spindle pins with grease meeting specification ESA-M1C75-B.
  6. Install a new seal on the Remover/Installer on the T side. Using the handle, push the seal into position in the bottom of the top bore.

Stabilizer Bar

REMOVAL & INSTALLATION

1997-98 F-Super Duty Chassis/Cab

Front stabilizer bar installation for F-Super Duty chassis/cab

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  1. Raise and support the front end on jackstands.
  2. Disconnect each end of the bar from the links.
  3. Disconnect the bar from the axle.
  4. Unbolt and remove the links from the frame.
  5. Installation is the reverse of removal. Replace any worn or cracked rubber parts. Install the bar loosely and make sure it is centered between the leaf springs. Make sure the insulators are seated in the retainers. When everything is in proper order, tighten the stabilizer bar-to-axle mounting bolts to 35-50 ft. lbs. (47-68 Nm). Tighten the end link-to-frame bolts to 52-74 ft. lbs. (71-100 Nm). Tighten the bar-to-end link nuts to 15-25 ft. lbs. (20-34 Nm).

1997-98 F-Super Duty Stripped Chassis or Motor Home Chassis

  1. Raise and support the front end on jackstands.
  2. Disconnect the stabilizer bar ends from the links attached to the axle.
  3. Remove the bar-to-frame bolts and remove the bar.
  4. Remove the links from the axle brackets.
  5. Installation is the reverse of removal. Replace any worn or cracked rubber parts. Assemble all parts loosely and make sure the assembly is centered on the frame. make sure that the insulators are seated in the retainers. When everything is in proper order, tighten the bar-to-frame brackets bolts to 30-47 ft. lbs. (41-64 Nm). Tighten the link-to-axle bracket bolts to 57-81 ft. lbs. (77-110 Nm). Tighten the bar-to-link nuts to 15-25 ft. lbs. (20-34 Nm).

Track Bar

REMOVAL & INSTALLATION

Chassis/Cab Models

Track bar installation—1997-98 F-Super Duty

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  1. Raise and support the front end on jackstands.
  2. Unbolt the track bar from the crossmember bracket.
  3. Unbolt the track bar from the axle bracket.
  4. Installation is the reverse of removal. Tighten the bolts at each end to 120-150 ft. lbs. (163-203 Nm).

Front Wheel Bearings

REMOVAL & INSTALLATION

1997-98 F-Super Duty

  1. Raise and support the front end on jackstands.
  2. Remove the wheel cover. Remove the wheel.
  3. Remove the caliper from the disc and wire it to the underbody to prevent damage to the brake hose.
  4. Remove the grease cap from the hub. Then, remove the cotter pin, nut lock, adjusting nut and flat washer from the spindle. Remove the outer bearing assembly from the hub.
  5. Pull the hub and disc assembly off the wheel spindle.
  6. Remove and discard the old grease retainer. Remove the inner bearing cone and roller assembly from the hub.
  7. Clean all grease from the inner and outer bearing cups with solvent. Inspect the cups for pits, scratches, or excessive wear. If the cups are damaged, remove them with a drift.
  8. Clean the inner and outer cone and roller assemblies with solvent and shake them dry. If the cone and roller assemblies show excessive wear or damage, replace them with the bearing cups as a unit.
  9. Clean the spindle and the inside of the hub with solvent to thoroughly remove all old grease.
  10. Covering the spindle with a clean cloth, brush all loose dirt and dust from the brake assembly. Remove the cloth carefully so as to not get dirt on the spindle.
  11. If the inner and/or outer bearing cups were removed, install the replacement cups on the hub. Be sure that the cups seat properly in the hub.
  12. It is imperative that all old grease be removed from the bearings and surrounding surfaces before repacking. The new lithium-based grease is not compatible with the sodium base grease used in the past.
  13. Install the hub and disc on the wheel spindle. To prevent damage to the grease retainer and spindle threads, keep the hub centered on the spindle.
  14. Install the outer bearing cone and roller assembly and the flat washer on the spindle. Install the adjusting nut.
  15. Adjust the wheel bearings by torquing the adjusting nut to 17-25 ft. lbs. (23-34 Nm) with the wheel rotating to seat the bearing. Then back off the adjusting nut 1/2 turn. Retighten the adjusting nut to 10-15 inch lbs. (1-1.7 Nm). Install the lock-nut so that the castellations are aligned with the cotter pin hole. Install the cotter pin. Bend the ends of the cotter pin around the castellations of the lock-nut to prevent interference with the radio static collector in the grease cap. Install the grease cap.
WARNING
New bolts must be used when servicing floating caliper units. The upper bolt must be tightened first.
  1. Install the wheels.
  2. Install the wheel cover.

Wheel Alignment

Refer to wheel alignment under 2 wheel drive coil spring suspension.

Chilton® Automotive Information Systems. © 2004 Thomson Delmar Learning.