Ford Axles

FIG. 5 Lock Axle for Total Backlash Check-Ford F-Series Axles:

FIG. 6 Lock Axle for Total Backlash Check-Ford E-150 and FIG-150 (later production) Axles:

Raise vehicle on hoist. Use a rigid bar or pipe of suitable length and clamp one end to the axle companion flange using Companion Flange Holding Tool T57T-4851-B, for F-Series (half-round flange), and T78P-4851-A for E-Series (circular flange), and the other end to the frame or body member in order to prevent movement of the companion flange (Fig. 5 or Fig. 6).

NOTE: Remove driveshaft when performing this procedure on E-Series.

Lower the vehicle so that one rear wheel is resting on a wheel chock to prevent it from turning. The other rear wheel will then be used to measure total axle backlash.

Rotate the free wheel slowly until a feel of driving the axle is encountered. Position a crayon or chalk firmly on the side of the tire 305 mm (12 inches) from the center of the wheel. Rotate the wheel slowly in the opposite direction until the feel of driving the axle is encountered again.

Measure the length of the crayon or chalk mark on the tire. If the length of the mark is 25.4mm (1 inch) or less, the axle backlash is within allowable limits.

If the chalk mark is greater than 1 inch, check for these conditions:

1. Elongation of the differential pinion shaft holes in the differential case.
2. Missing differential, pinion, or side gear thrust washers.
3. Galling of the differential pinion shaft and bore.
4. Excessive gear set backlash. Follow procedure for type of axle, to check backlash.