Inspect, Remove and Install a Strut
McPherson struts often have a service life in excess of 100,000 miles. However, there are some occasions when the strut must be removed or replaced before this milestone is reached. One such case is if the strut begins to leak fluid. A broken coil spring can also mean a coil-over-strut replacement. In either case, the strut must be removed from the vehicle.
Strut removal is a rather straightforward procedure, but in order to remove the coil spring, a spring compressor is required. Most auto parts stores rent spring compressors for a nominal fee.
Strut Removal
Lift the vehicle off the ground and support it with a jack stand. Remove the tire and wheel assembly and inspect the strut assembly. Check the coil spring, looking for damaged or broken coils. Inspect the dust boot for cracks or tears. Finally, inspect the strut assembly for evidence of fluid leaking from the upper end of the fluid reservoir (see Figure 1). Lift the dust boot, A, and look for fluid at the point where the rod extends upward from the top of the strut assembly, B. A slight amount of seepage of fluid is not unusual, but fluid dripping down the side of the strut assembly indicates a serious problem and requires strut replacement.
After the inspection is finished, we can begin to remove the strut. First, remove the brake hose routing bracket and speed sensor cable routing bracket from the strut assembly. Next, remove the stabilizer bar link, C, from the bracket on the strut assembly, D, as shown in Figure 2. Do not rotate the mounting stud of the link; rather, place a wrench on the flat and remove the nut.
Next, remove the two attaching bolts (see Figure 3). These bolts attach the clevis bracket, E, to the steering knuckle, F. Remove the nut, G, from the bolt, H. Do not rotate the bolt, as the shoulder is serrated. Use a plastic hammer to tap the bolts from the bracket and knuckle.
To complete the removal of the strut assembly, remove the three attaching nuts, J, from the upper mount studs that secure the strut assembly to the strut tower, K (see Figure 4). Once these nuts are removed, the entire strut assembly can be removed from the vehicle.
Strut Disassembly
In order to disassemble the strut assembly, a spring compressor, such as the Pentastar Service Equipment (PSE) tool W-7200, or equivalent is required to compress the coil spring. NOTE: Always exercise extreme caution when compressing the spring and always wear eye protection. Place the bottom of the coil spring, L, on the lower hooks, M, as shown in Figure 5. Next, position the upper hooks on top of the upper spring seat approximately one inch from the outside diameter of the seat.
With the lower end of the coil spring held in place with a clamp, compress the coil spring to remove all tension on the upper mount, N. Install Strut Service Nut, Special Tool 6864 (this should also be available for rent), O, on the strut retaining nut within the upper mount, N. Next, install a 10 mm socket, P, on the hex on the end of the strut shaft. While holding the strut shaft from turning with a 1/2" drive ratchet, Q, remove the nut from the strut shaft (see Figure 6).
Remove the upper mount from the strut shaft, as well as the pivot bearing. Remove the clamp from the bottom of the coil spring and remove the strut through the bottom of the coil spring. Remove the dust shield and jounce bumper as a unit, then remove the spring isolator from the lower spring seat on the strut.
Release the tension from the coil spring, push back on the upper hooks and remove the upper spring seat and upper spring isolator. The coil spring can now be removed from the spring compressor.
Strut Assembly
After the strut assembly is disassembled, inspect the individual components and replace any that are broken or damaged. Now we’re ready to reassemble the strut assembly. Place the bottom of the coil spring in the lower hooks of the spring compressor (just as we did in Figure 5). Position the coil spring in the compressor so that the end of the coil (on the bottom end) is at the back of the compressor. Install the upper seat and upper isolator on the top of the spring. Position the upper hooks on the upper seat approximately one inch from the edge of the seat. Install the pivot bearing.
Compress the coil spring to allow the strut to be installed. Install the spring isolator on the lower spring seat, then install the jounce bumper, with the small end pointing upward. Install the dust boot on the strut (be sure that the boot snaps into place on the jounce bumper). Now, install the strut through the bottom of the coil spring until the lower spring seat contacts the lower end of the spring. The clevis bracket on the strut (shown as E in Figure 3) should be aligned with the slot in the upper spring seat, R, as shown in Figure 7. If necessary, re-position the spring and/or strut to achieve this alignment.
To finish the assembly, install the strut mount, N, in Figure 6, over the strut shaft and loosely install the retaining nut. Using the same special tools used in removal (see Figure 6), tighten the strut retaining nut. Slowly release the tension of the coil spring by backing off the compressor.
Strut Installation
Strut installation is simple, just reversing the steps of the removal procedure. Install the strut assembly, positioning the top of the assembly in the strut tower. Install the three attaching nuts shown in Figure 4. Position the clevis bracket, S, of the new strut over the steering knuckle, T, as shown in Figure 8, then install the two attaching bolts. Also, mark points where camber bolts attach to help maintain proper alignment.
Next, connect the stabilizer bar link to the bracket on the strut assembly. Finally, connect the brake hose routing bracket and speed sensor cable routing bracket to the brackets on the strut assembly. Note: After installing new struts, always perform a complete wheel alignment.
