VW Passat & Audi A4 1990-2000

MacPherson Struts

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REMOVAL & INSTALLATION
1990-97 Passat Models

The upper strut-to-steering knuckle bolt may have an eccentric washer for adjusting wheel camber. Use a wire brush to clean the area and use a cold chisel to mark a fine line on the washer and the strut together. This matchmark may be enough to preserve the front wheel camber adjustment. It will at least be accurate enough to allow driving the vehicle until a proper front wheel alignment can be performed. If there is no eccentric washer, a new bolt and eccentric washer can be substituted. The parts are available through the dealer.

A special tool is required to remove the upper strut nut. If necessary, it can be made by cutting away part of a 22mm ( 7 / 8 inch) or the equivalent socket.

  1. Note the radio security code and disconnect the negative battery cable.
  2.  
  3. Loosen the front lug bolts slightly but Do NOT remove.
  4.  
  5. Raise and safely support the vehicle.
  6.  
  7. Remove the front wheel(s).
  8.  
  9. If equipped, disconnect the ABS wheel speed sensor.
  10.  
  11. Clean and matchmark the position of the strut-to-steering knuckle bolt.
  12.  
  13. Remove the bolts and push the steering knuckle down away from the strut. Support the knuckle so it is not hanging on the outer CV joint. If necessary, disconnect the stabilizer bar from the lower control arm.
  14.  
  15. Use a hex wrench to hold the shock absorber rod and use the cut away socket to remove the upper nut. Lower the strut from the vehicle.
  16.  



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Fig. An exploded view of the Passat GLX front suspension



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Fig. Matchmark the strut-to-knuckle location before removal



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Fig. Two closed end wrenches are needed to loosen the strut to knuckle bolts



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Fig. Note the location of the strut to knuckle bolts



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Fig. Pull the knuckle far enough away from the strut to allow removal of the strut.



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Fig. Remove the strut mounting plate cap



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Fig. A socket and an Allen® key are needed to remove the strut-mounting nut



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Fig. Strut mounting plate and nut



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Fig. Remove the strut assembly from the vehicle

To install:

  1. Place the strut into the inner fender and install a new center nut and tighten it to 44 ft. lbs. (60 Nm).
  2.  
  3. Fit the knuckle into the strut and install the bolts. Be sure the matchmarks are aligned and install the nuts and tighten the bolts to 70 ft. lbs. (95 Nm).
  4.  
  5. Install the wheel(s) and torque the wheel lug bolts, based on size, to:
  6.  
  7. M12 x 1.5: 81 ft. lbs. (110 Nm)
  8.  
  9. M14 x 1.5: 89 ft. lbs. (120 Nm)
  10.  
  11. Check and align the front wheels as necessary.
  12.  

A4 & 1998-00 Passat Models
  1. Note the radio security code and disconnect the negative battery cable.
  2.  
  3. Loosen the front lug bolts slightly, but Do NOT remove.
  4.  
  5. Raise and safely support the vehicle.
  6.  
  7. Remove the front wheel(s).
  8.  
  9. Remove the grommets under the hood to access the upper strut mounting fasteners, then loosen and remove the fasteners.
  10.  
  11. Remove the ABS sensor electrical cable from the support bracket near the brake caliper.
  12.  
  13. Loosen the pinch bolt and nut for the upper control arms and remove the arms from the bearing holder (knuckle). Do NOT pry or wedge the open the slotted area of the bearing holder.
  14.  
  15. Pivot the bearing holder assembly forward and remove the lower strut clevis mounting bolt and nut, then remove the strut assembly.
  16.  



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Fig. Loosen and remove the pinch bolt (1) and remove upper arms (2). Do NOT loosen or remove the tie rod end (Nos. 3 and 4)

To install:

  1. Installation is in reverse order of removal noting the following:
  2.  
  3. Install the strut assembly with the spring perch drain hole facing toward the middle of the vehicle.
  4.  
  5. Tighten the mounting fasteners as follows:
  6.  
  7. Bearing holder upper control arm pinch bolt: 30 ft. lbs. (40 Nm)
  8.  
  9. Front strut-to-control arm: 66 ft. lbs. (90 Nm)
  10.  
  11. Front upper strut-to-body: 15 ft. lbs. (20 Nm)
  12.  
  13. Wheel lug bolts: 89 ft. lbs. (120 Nm)
  14.  

OVERHAUL

If the strut housing retains the dampener assembly with a threaded cap, a dampener insert may be available separately from the entire strut assembly. Consult you local parts vendor or shock absorber manufacturer for availability and specific installation details.

Some special tools will be necessary to disassemble the strut such as a suitable spring compressor, a sturdy vise, and a tool capable of removing the cap nut, such as a large pipe wrench.


CAUTION
The coil spring is very strong and under considerable pressure. If the correct tools and techniques are not available, Do NOT attempt this job. Improper handling of coil springs can cause serious or fatal injury.

  1. Remove the strut.
  2.  
  3. Anchor the strut in a vise so it cannot move and attach the spring compressor.
  4.  
  5. Remove the spring.
  6.  
  7. Use a suitable pipe wrench to remove the threaded collar from the top of the strut. Remove the strut from the vice and pour the fluid into a suitable drain pan.
  8.  
  9. Remove the strut rod and discard all the internal parts.
  10.  

To install:

  1. Most replacement inserts are a self-contained gas pressure shock absorber. Follow the shock insert manufacturers directions for installation of their inserts. Typically it may be recommended to pour about 2 ounces of fresh ATF into the strut housing and then install the new insert. The fluid will help dissipate heat and extend the life of the insert.
  2.  
  3. Install the threaded collar and tighten it to 30 ft. lbs. (40 Nm).
  4.  
  5. Fit the spring into place, install the upper seat and start the nut onto the rod. It may be easier to tighten the nut before removing the spring compressor. Tighten the nut to the manufacturer's recommended torque then carefully remove the spring compressor and install the strut assembly.
  6.  

TESTING

The purpose of the shock absorber or dampener portion of the strut assembly is simply to limit the sudden motion of the spring during compression and rebound cycles. If the vehicle is not equipped with these motion dampers, the up and down motion would multiply until the vehicle was alternately trying to leap off the ground and to pound itself into the pavement.

Contrary to popular rumor, unless gas charged, the shocks Do NOT affect the ride height of the vehicle. This is controlled by other suspension components such as springs and tires. Worn dampeners can affect handling; if the front of the vehicle is rising or falling excessively, the "footprint" of the tires changes on the pavement and steering is affected.

The simplest test of the dampener is simply push down on one corner of the unladen vehicle and release it. Observe the motion of the body as it is released. In most cases, it will come up beyond it original rest position, dip back below it and settle quickly to rest. This shows that the damper is controlling the spring action. Any tendency to excessive pitch (up-and-down) motion or failure to return to rest within 2-3 cycles is a sign of poor function within the shock absorber. Oil-filled dampers may have a light film of oil around the seal, resulting from normal breathing and air exchange. This should NOT be taken as a sign of failure, but any sign of thick or running oil definitely indicates failure. Gas filled struts may also show some film at the shaft; if the gas has leaked out, the shock will have almost no resistance to motion.

Each strut or if equipped with cartridge type struts, the dampener insert can be replaced individually, although it is recommended that they be changed as a pair (both front or both rear) to maintain equal response on both sides of the vehicle. Chances are quite good that if one has failed, its mate is weak also.


NOTE
When replacing struts or inserts, always make sure they are a matched set, or for one strut, make sure it matches the strut not being replaced.



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Fig. When fluid is seeping out of the dampener, it's time to replace the strut

 
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