Ford F150 Pickup. Manual — part 647

Fig. 27: Comparing Two High Points Marked
Courtesy of FORD MOTOR CO.

If the marks are on opposite sides of the driveshaft, the yoke or pinion flange is responsible for the
vibration.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 28: Identifying Yoke Or Pinion Flange Is Responsible For Vibration
Courtesy of FORD MOTOR CO.

When installing a new pinion flange, the driveshaft runout must not exceed 0.89 mm (0.035 inch). When
runout is within limits, recheck for vibration at road speed. If vibration persists, balance the driveshaft.

7. To balance the driveshaft, install one or two hose clamps on the driveshaft, near the rear. Position of the

hose clamp head(s) can be determined by trial-and-error.

8. Mark the rear of the driveshaft into four approximately equal sectors and number the marks 1 through 4.

Install a hose clamp on the driveshaft with its head at position No. 1.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 29: Identifying Mark Rear Of Driveshaft Into Four Approximately Equal Sectors
Courtesy of FORD MOTOR CO.

Check for vibration at road speed. Recheck with the clamp at each of the other positions to find the
position that shows minimum vibration. If two adjacent positions show equal improvement, position the
clamp head between them.

9. If the vibration persists, add a second clamp at the same position and recheck for vibration.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup

Fig. 30: Identifying Vibration Persists, Add A Second Clamp At Same Position And Recheck For
Vibration
Courtesy of FORD MOTOR CO.

If no improvement is noted, rotate the clamps in opposite directions, equal distances from the best
position determined in Step 8. Separate the clamp heads about 13 mm (1/2 inch) and recheck for vibration
at the road speed.

2003 Ford Pickup F150

2003 GENERAL INFORMATION Driveline System - General Information - F150 Pickup