Ford F150 Pickup. Instruction — part 649

The axle shaft must turn with even pressure throughout the check without slipping or binding. If the torque
reading is less than specified, check the differential case. Refer to REAR DRIVE AXLE/DIFFERENTIAL-
FORD 8.8-INCH or REAR DRIVE AXLE/DIFFERENTIAL-FORD 9.75-INCH .

Traction-Lokohm Differential Check Road Test

1. Place one wheel on a dry surface and the other wheel on ice, mud or snow.

2. Gradually open the throttle to obtain maximum traction prior to break away. The ability to move the

vehicle demonstrates correct operation of a Traction-Lokohm rear axle assembly (4006).

3. When starting with one wheel on an excessively slippery surface, a slight application of the parking brake

may be necessary to help energize the Traction-Lokohm feature of the differential. Release the brake
when traction is established. Use light throttle on starting to provide maximum traction.

4. If, with unequal traction, both wheels slip, the limited slip rear axle has done all it can possibly do.

5. In extreme cases of differences in traction, the wheel with the least traction may spin after the Traction-

Lokohm has transferred as much torque as possible to the non-slipping wheel.

Pinion Flange Runout Check - Circular

1. Raise the vehicle on a twin-post hoist that supports the rear axle.

2. Remove the driveshaft. Refer to DRIVESHAFT & UNIVERSAL JOINTS - F150 PICKUP .

3. Check the pinion flange for damage.

4. Position the special tool on the pinion flange.

CAUTION: Pinion bearing preload must be reset if the pinion nut has been loosened

or removed for pinion flange reindexing or installation.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 34: Positioning Special Tool On Pinion Flange
Courtesy of FORD MOTOR CO.

5. Position the special tool onto the pinion flange.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 35: Positioning Special Tool Onto Pinion Flange
Courtesy of FORD MOTOR CO.

6. Align the holes on the clamp plate with the holes in the pinion flange and install the bolts. Snug the bolts

evenly.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 36: Aligning Holes On Clamp Plate With Holes In Pinion Flange
Courtesy of FORD MOTOR CO.

7. Position the special tool as shown. Turn the special tool, and locate and mark the high spot on the pinion

flange with yellow paint.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup