Ford F150 Pickup. Instruction — part 648

Fig. 31: Separating Clamp Heads About And Recheck For Vibration At Road Speed
Courtesy of FORD MOTOR CO.

Repeat the process with increasing separation until the best combination is found or the vibration is
reduced to an acceptable level.

10. Install the wheels and road test (vibration noticeable on the hoist may not be evident during the road test).

If the vibration is still not acceptable, install a new axle drive line vibration damper first, if so equipped. If
the vibration is still not acceptable, refer to REAR DRIVE AXLE/DIFFERENTIAL-FORD 8.8-INCH
or REAR DRIVE AXLE/DIFFERENTIAL-FORD 9.75-INCH for differential case and ring gear
runout checks.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Driveshaft Vibrates

1. Road test the vehicle to determine the critical vibration points. Note the road speed, the engine rpm, and

the shift lever positions at which the vibration occurs.

2. Stop the vehicle, place the transmission lever in neutral and run the engine through the critical speed

ranges determined in Step 1.

3. If no vibration is felt, balance the driveshaft. Refer to DRIVELINE VIBRATION .

Traction-Lokohm Differential Operation Check

A Traction-Lokohm differential can be checked for correct operation without removing it from the rear axle
housing (4010).

Raise and remove only one rear wheel. Install the special tool on the wheel bolts.

WARNING:

A vehicle equipped with a Traction-Lokohm differential will always have
both wheels driving. If only one wheel is raised off the floor and the rear
axle is driven by the engine, the wheel on the floor could drive the vehicle
off the stand or jack. Be sure both rear wheels are off the floor.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 32: Removing Only One Rear Wheel
Courtesy of FORD MOTOR CO.

Use a torque wrench with the capacity of at least 271 Nm (200 lb-ft) to rotate the axle shaft. Be sure that the
transmission is in NEUTRAL, and that one rear wheel is on the floor while the other rear wheel is raised off the
floor. The breakaway torque required to start rotation must be at least 27 Nm (20 lb-ft). The initial breakaway
torque may be higher than the continuous turning torque.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 33: Identifying Initial Breakaway Torque May Be Higher Than Continuous Turning Torque
Courtesy of FORD MOTOR CO.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup