How to Install the Front Brake Rotors on a 96 BMW 740IL

The 7-Series made its debut on U.S. soil in the 1986 model year, giving the BMW name the full-size, full luxury presence it was lacking. In 1996, the 10-year-anniversary model year of the 7-Series, two models were released: the 740iL and 750iL. The 740iL came standard with four-wheel-disc brakes and an antilock brake system. It also had a sensor mounted on the inner brake pad that alerted the driver, via a light on the dashboard, when the brake pads were wearing thin. Replacing the front rotors on this luxurious vehicle is slightly unorthodox, but it is still a straightforward process.

Instructions

1

Loosen the BMWs front wheel bolts with a ratchet and socket. Raise the front of the vehicle with a floor jack and place jack stands under its frame rails. Lower the 740iL onto the jack stands. Remove the wheel bolts and remove the front wheels.

2

Trace the brake pad level sensor wire -- on the drivers side only -- until you find where it connects to the BMWs wiring harness. Press and hold the unlocking button on the wiring harness, then unplug it from the vehicles harness. Unfasten the retaining bolt that secures the pad level sensor bracket to the caliper, using a ratchet and socket, and pull the level sensor wire from its routing clip.

3

Instruct an assistant to press and hold the brake pedal. Remove the rotor-retaining screw in the center of the rotor with a ratchet and a hex-bit socket.

4

Find the out caliper-retaining clip -- the metal clip on the outer part of the caliper. Remove this clip by prying it out with a flat-head screwdriver.

5

Pull the plastic caps covering the caliper bolts from the caliper. Remove the two caliper pins with a ratchet and hex-bit socket, then pull the caliper up and out of the caliper bracket. Hang the caliper from a nearby suspension component with a bungee cord. If the outer brake pad did not fall out when you removed the caliper, pull the pad from the caliper.

6

Remove the two caliper bracket bolts with a ratchet and socket. Pull the caliper bracket off the steering knuckle.

7

Pull the rotor of the 740iLs hub. If the rotor does not pull off easily, lightly tap it with a rubber mallet to free it. Set a new rotor on the front hub, lining up its screw hole with that in the hub. Hand-tighten the rotor-retaining screw. Hold the rotor firmly to prevent it from turning, then tighten the rotor-retaining screw to 12 foot-pounds with a torque wrench and socket.

8

Set the caliper bracket back on the front steering knuckle and hand-thread its retaining bolts. Torque the caliper bracket bolts to 81 foot-pounds with a torque wrench and socket.

9

Position a drain pan under the caliper. Place an 8-inch C-clamp over the caliper so that its fixed part touches the rear of the caliper body and its screw part contacts the inner brake pad. Tighten the C-clamp until it touches the inner brake pad, then set a combination wrench on the bleeder valve -- the -inch metal valve -- on top of the caliper.

10

Turn the bleeder valve a half-turn counterclockwise to open it, then immediately start tightening the C-clamp to press the caliper piston into the caliper. Continue tightening the C-clamp until the piston stops moving, then immediately close the bleeder valve.

11

Pull the old inner brake pad from the caliper; notice that small metal clips hold it inside the cavity in the piston. The brake pad level sensor comes off with the inner brake pad. Line up the clips on the rear of the new inner brake pad with the cavity in the piston, then press the brake pad toward the piston until the pad is flat against the end of the piston. On the drivers side only, press a new pad level sensor into the groove on the top of the brake pad, nearest to the hole in the top of the caliper.

12

Set the outer brake pad in the caliper and immediately set the caliper on its bracket. Wipe all of the old grease off the caliper pins and apply a thin coat of new disc brake grease onto the smooth part of each pin. Hand-thread the caliper pins into the caliper, then torque them to 22 foot-pounds with a torque wrench and hex-bit socket.

13

Set the outer caliper-retaining clip so that the ends of its longest side are between the caliper bracket and the center hub of the rotor. Press the clip upward to insert its two tabs into the two holes in the outer part of the caliper.

14

Route the pad level sensor wiring in the same manner the old one was positioned. Hand-tighten the pad level sensor bracket bolt, then tighten it with a ratchet and socket. Press the pad level sensor wiring into the routing clip, then plug it into the BMWs wiring harness.

15

Press the plastic caps back in place over the caliper guide pins.

16

Repeat Steps 2 through 15 to replace the rotor on the other side of the 740iL.

17

Reinstall the front wheels on the 740iLs front hubs, then hand-tighten the wheel bolts. Raise the BMW off the jack stands with a floor jack and remove the jack stands. Lower the vehicle to the ground. Tighten the wheel bolts, in a crisscross pattern, to between 95 and 111 foot-pounds with a torque wrench and socket.

18

Press and release the brake pedal until it feels firm. Check the brake fluid level in the reservoir. Add DOT 4 brake fluid, as needed, to bring the level up to the Max" line on the reservoir.

19

Turn the ignition to the 1 position and leave it in that position for at least 30 seconds to reset the brake pad level light. Turn the ignition off.