Ford Mustang 1989-1993 Repair Guide

MacPherson Strut


See Figures 1 and 2

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Fig. Fig. 1: Exploded view of the front strut upper mounting

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Fig. Fig. 2: Exploded view of the front suspension assembly-including front strut


Bounce Test

Each strut can be tested by bouncing the corner of the vehicle until maximum up and down movement is obtained. Let go of the vehicle and watch. It should stop bouncing in 1-2 bounces. If not, the strut should be inspected for damage and possibly replaced.

Strut Mounts

Check the strut mountings for worn or defective grommets, loose mounting nuts, interference or missing bump stops. If no apparent defects are noted, check the strut for hydraulic leaks.

Checking for Hydraulic Leaks

Disconnect each strut lower mount and pull down on the strut until it is fully extended. inspect for leaks in the seal area. Strut fluid is very thin and has a characteristic odor and dark brown color. Don't confuse the glossy paint on some struts with leaking fluid. A slight trace of fluid is a normal condition; they are designed to seep a certain amount of fluid past the seals for lubrication. If you are in doubt as to whether the fluid on the strut is coming from the strut itself or from some other source, wipe the seal area clean and manually operate the strut (refer to the procedure later in this section). Fluid will appear if the unit is leaking.

Manually Operating the Struts

It may be necessary to fabricate a holding fixture for certain types of strut absorbers. If a suspected problem is in the front struts, disconnect both front strut lower mountings.

Grip the lower end of the strut and pull down (rebound stroke) and then push up (compression stroke). The control arms will limit the movement of front struts during the compression stroke. Compare the rebound resistance of both struts and compare the compression resistance. Usually any strut showing a noticeable difference will be the one at fault.

If the strut has internal noises, extend the strut fully then exert an extra pull. If a small additional movement is felt, this usually means a loose piston, and the strut should be replaced. Other noises that are cause for replacing struts are a squeal after a full stroke in both directions, a clicking noise on fast reverse and a lag at reversal near mid-stroke.


See Figures 3, 4 and 5

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Fig. Fig. 3: Loosen the three upper mount retaining nuts

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Fig. Fig. 4: Matchmark the strut and spindle (knuckle) to assure proper wheel alignment is maintained ...

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Fig. Fig. 5: ... then loosen the strut lower fasteners (a backup wrench is necessary to keep the nuts/bolts from spinning)

  1. Disconnect the negative battery cable.
  3. Place the ignition switch in the unlocked position to permit free movement of the front wheels.
  5. Raise the vehicle by the lower control arms until the wheels are just off the ground. From the engine compartment, remove and discard the three upper mount retaining nuts. Do not remove the pop-rivet holding the camber plate in position.
  7. Continue to raise the front of the vehicle by the lower control arms and position jackstands under the frame jacking pads, rearward of the wheels.
  9. Remove the wheel and tire assembly, then remove the brake caliper. Support the caliper with a length of wire; do not let the caliper hang by the brake hose.

To help assure that wheel alignment is not changed, place matchmarks on the strut and spindle (steering knuckle) before removal. If the strut is being replaced, carefully transfer the marks to the new part.

  1. Remove the two lower nuts that attach the strut to the spindle, leaving the bolts in place. Carefully remove both spindle-to-strut bolts, push the bracket free of the spindle and remove the strut.
  3. Compress the strut to clear the upper mount of the body mounting pad. If necessary, remove the upper mount and jounce bumper.

To install:
  1. If removed, install the upper mount and jounce bumper.
  3. Position the three upper mount studs into the body mounting pad and camber plate, then start three new nuts.
  5. Compress the strut and position into the spindle. Install two new lower retaining bolts and hand start the nuts. Remove the suspension load from the control arms by lowering the vehicle. Tighten the lower retaining nuts to 140-200 ft. lbs. (190-271 Nm).
  7. Raise the suspension control arms (to position the suspension at normal ride height) and tighten the upper mount retaining nuts to 40-55 ft. lbs. (54-75 Nm).
  9. Install the brake caliper.
  11. Install the wheel and tire assembly.
  13. Remove the jackstands and carefully lower the vehicle to the ground.
  15. Check the front end alignment and adjust, as necessary.