Diesel Data: Automotive Repair

Front Steering Knuckle: Service and Repair


REMOVAL - STEERING KNUCKLE (FRONT)

NOTE: Before proceeding, review all Warnings and Cautions.

1. Apply the brakes and hold in place.
2. Raise the vehicle.
3. Remove the front tire and wheel assembly.





4. Remove the cotter pin, lock nut and spring washer from the hub nut (Fig. 2).
5. While the brakes are applied, loosen and remove the hub nut on the end of the driveshaft (Fig. 2).
6. Release the brakes.
7. Remove the front disc brake caliper and adapter as an assembly, and the brake rotor from the steering knuckle.





8. Remove the nut attaching the outer tie rod to the steering knuckle. To do this, hold the tie rod end stud with a wrench while loosening and removing the nut with a standard wrench or crowfoot wrench (Fig. 4).





9. Remove the tie rod end from the steering knuckle using Remover, Special Tool MB991113 (Fig. 5).
10. Remove the tie rod heat shield.





11. Remove the nut and pinch bolt clamping the ball joint stud to the steering knuckle (Fig. 6).

CAUTION: The strut assembly-to-steering knuckle attaching bolts are serrated and must not be turned during removal. Hold the bolts stationary in the steering knuckles while removing the nuts, then tap the bolts out using a pin punch.

12. Remove the two bolts attaching the strut to the steering knuckle.

NOTE: Use caution when separating the ball joint stud from the steering knuckle, so the ball joint seal does not get cut.





13. Separate the ball joint stud from the steering knuckle by prying down on lower control arm and up against the ball joint boss on the steering knuckle (Fig. 7).

NOTE: Do not allow the driveshaft to hang by the inner C/V joint; it must be supported to keep the joint from separating during this operation.

14. Pull the steering knuckle off the driveshaft outer C/V joint splines and remove the steering knuckle.

NOTE: The cartridge type front wheel bearing used on this vehicle is not transferable to the replacement steering knuckle. If the replacement steering knuckle does not come with a wheel bearing, a new bearing must be installed in the steering knuckle. Installation of the new wheel bearing and hub must be done before installing the steering knuckle on the vehicle.

15. If the wheel bearing and hub need removal, Refer to KNUCKLE - DISASSEMBLY. Do not reuse the wheel bearing.

DISASSEMBLY - WHEEL BEARING AND HUB

NOTE: The removal and installation of the wheel bearing and hub from the steering knuckle is only to be done with the steering knuckle removed from the vehicle using the procedure.

1. Remove steering knuckle, hub, and wheel bearing as an assembly from the vehicle.

Part 1 Of 2:




Part 2 Of 2:





2. Three wheel studs across from one another require removal from the hub flange. Rotate the hub to align each wheel mounting stud with the notch in the bearing retainer plate before removal. Using Remover, Special Tool C-4150A (Fig. 24), press the three wheel mounting studs out of the hub flange. Remove the wheel mounting studs from the hub through the open notch (Fig. 25).





3. Rotate the hub so the stud mounting holes in the hub are facing in the direction shown in the figure (Fig. 26).
4. Install the Bearing Splitter, Special Tool 1130, between the hub and the bearing retainer plate as shown (Fig. 26). Absence of the three wheel mounting studs allows the bearing splitter to be installed behind the flange. Hand tighten the nuts to hold bearing splitter in place on steering knuckle.





5. Place the steering knuckle face down in an arbor press supported by the bearing splitter as shown (Fig. 27).
6. Position Remover/Installer, Special Tool 6644-2, on the small end of the hub (Fig. 27). Using the arbor press, remove the hub from the wheel bearing. The bearing race will normally come out of the wheel bearing with the hub as it is pressed out of the bearing.
7. Remove the bearing splitter from the steering knuckle.





8. Remove the three bolts mounting the bearing retainer plate to the steering knuckle (Fig. 28). Remove the bearing retainer plate from the steering knuckle.





9. Place the steering knuckle back in the arbor press face down as shown (Fig. 29). The press support blocks must not obstruct the bearing while it is being pressed out of the steering knuckle.
10. Place Remover/Installer, Special Tool MB-990799 on the outer race of the wheel bearing (Fig. 29). Press the wheel bearing out of the steering knuckle.





11. Remove the bearing race that is still pressed onto the hub. To do so, install Bearing Splitter, Special Tool 1130, between the hub flange and the bearing race (Fig. 30). Place the hub, bearing race and bearing splitter in an arbor press as shown (Fig. 30). Place Remover/Installer, Special Tool 6644-2 on end of hub. Press the hub out of the bearing race.

NOTE: For steering knuckle reassembly, Refer to KNUCKLE - ASSEMBLY.

ASSEMBLY - WHEEL BEARING AND HUB
1. Wipe the bore of the steering knuckle clean of any grease or dirt with a clean, dry shop towel.





2. Place the steering knuckle in an arbor press with Installer, Special Tool C-4698-2, supporting the steering knuckle (Fig. 31).
3. Place the NEW wheel bearing into the bore of the steering knuckle. Be sure the wheel bearing is placed squarely into the bore.
4. Place Installer, Special Tool 5052, on the outer race of the wheel bearing (Fig. 31). Press the wheel bearing into the steering knuckle until it is fully bottomed in the bore of the steering knuckle.
5. Remove the knuckle from the press.

NOTE: Use only the original or identical replacement bolts to mount the bearing retainer plate to the steering knuckle.

6. Noting the notch location, install the bearing retainer plate on the steering knuckle as shown (Fig. 28). Install the three bearing retainer mounting bolts. Tighten the bearing retainer plate mounting bolts to a torque of 28 Nm (250 inch lbs.).
7. Install the previously removed wheel mounting studs back into the hub flange. To do so:
a. Place the studs in the three holes in the hub flange.





b. Place the hub in the arbor press supported by Special Tool C-4698-1, allowing the first stud to extend down into the tool (Fig. 32).
c. Press the wheel mounting stud into the hub flange until it is fully seated against the back side on the hub flange.
d. Remove the hub and tool from the press.
e. Repeat the steps (b), (c) and (d) on the remaining two studs.





8. Place the steering knuckle with the wheel bearing installed back in the arbor press with the smaller end of Remover/Installer, Special Tool MB-990799, supporting the inner race of the wheel bearing as shown (Fig. 33).
9. Place the hub in the wheel bearing making sure it is square with the bearing inner race (Fig. 33). Press the hub into the wheel bearing until it is fully bottomed in the wheel bearing.
10. Remove the steering knuckle and tools from the press.
11. Verify the hub turns smoothly without rubbing or binding.
12. Install the steering knuckle on the vehicle.

INSTALLATION
1. Slide the hub of the steering knuckle onto the splines on the driveshaft C/V joint.
2. Install the steering knuckle onto the ball joint stud aligning the bolt hole in the knuckle boss with the notch formed in the side of the ball joint stud.
3. Install a new ball joint stud pinch bolt and nut (Fig. 6). Tighten the nut to a torque of 95 Nm (70 ft. lbs.).

CAUTION: The strut assembly-to-steering knuckle attaching bolts are serrated and must not be turned during installation. Install the nuts while holding the bolts stationary in the steering knuckle.

4. Position the lower end of the strut assembly in line with the upper end of the steering knuckle and align the mounting holes. Install the two attaching bolts. The bolts should be installed with so that the nuts face towards the front of the vehicle once installed. Install the nuts. Holding the bolts in place tighten the nuts to a torque of 53 Nm (40 ft. lbs.) plus an additional 90° turn after the specified torque is met.
5. Place the tie rod heat shield on the steering knuckle arm so that the shield is positioned straight away from the steering gear and tie rod end once installed. Align the hole in the shield with the hole in the steering knuckle arm.
6. Install the outer tie rod ball stud into the hole in the steering knuckle arm. Start the tie rod attaching nut onto the stud. Hold the tie rod end stud with a wrench while tightening the nut with a standard wrench or crowfoot wrench (Fig. 4). To fully tighten the nut to specifications, use a crowfoot wrench on a torque wrench to turn the nut, and a wrench on the stud. Tighten the nut to a torque of 55 Nm (40 ft. lbs.).
7. Install the brake rotor, disc brake caliper and adapter.
8. Clean all foreign matter from the threads of the driveshaft outer C/V joint.
9. Install the hub nut in the end of the driveshaft and snug it (Fig. 2).
10. Have a helper apply the brakes. With vehicle brakes applied to keep brake rotor and hub from turning, tighten the hub nut to a torque of 244 Nm (180 ft. lbs.).
11. Install the spring washer, lock nut and cotter pin on the hub nut (Fig. 2). Wrap the cotter pin ends tightly around the lock nut (Fig. 23).
12. Install the tire and wheel assembly. Install the wheel mounting nuts and tighten them to a torque of 135 Nm (100 ft. lbs.).
13. Lower the vehicle.
14. Set the front toe on the vehicle to required specification.