Q: How to remove,install and overhaul the strut on BMW M3?
A: To remove and install the strut on E30 models (except 320 IX models), start by disconnecting the negative battery cable and raising the vehicle. Remove the tire and wheel assembly, then disconnect the brake pad wear indicator plug, ground wire, and ABS pulse sender if equipped. Unbolt the caliper and suspend it with wire, being careful not to disconnect the brake line. Remove the push rod on the stabilizer bar and unscrew the ball joint stud and tie-rod joint. Press the bottom of the strut outward and push it over the ball joint stud, then unscrew the nuts at the top of the strut and remove it. To install, press the strut into the wheel housing, tighten the ball joint and top strut mounting nuts, install the tie rod and stabilizer bar link, and tighten the brake caliper. Finally, install the ABS sensor, brake pad wear sensor, and brake hose, and connect the negative battery terminal. For 320 IX models, follow similar steps but also lift out the lock plate at the center of the brake disc, remove the small rod at the strut, and press the output shaft out of the center of the knuckle. For E36 models, remove the wheel assembly, disconnect the brake line and wires, and remove the stabilizer bar link. Remove the lower strut-to-steering knuckle bolts, the upper through bolt and lock-nut, and carefully lower and remove the strut. To install, mount the strut into the inner fender strut tower, clean the threaded holes in the steering knuckle, and guide the strut onto the knuckle. Apply a locking agent to the strut-to-knuckle mounting bolts and tighten them. Install the stabilizer bar link, brake hose, and wires, then install the wheel and tire assembly and lower the vehicle. Have the alignment checked. For overhauling the strut, remove it from the vehicle and mount it in a vise using a strut holder. Use a spring compressor to compress the spring, then remove the top nut of the strut mount and pull off the mount. Pull the spring off the strut and replace it if necessary. On E30 models, remove the gland nut, old cartridge, and oil, then fill the strut tube with engine oil or ATF and install the new cartridge. If replacing the spring, carefully remove the spring compressor and transfer the rubber spring seats to the replacement strut. Inspect the spring mount cushion and bearing condition and replace if necessary.