Ford 9.75 inch Axle

Ford 9.75 in Differential Specs & Information

The 9.75 inch Ford rear differential was introduced as a higher capacity alternative to the Ford 8.8 inch. A maximum gross axle weight rating of 4,500 lbs makes it relatively robust for a semi floating axle. The 9.75" differential has been historically reserved for Ford F-150s with a relatively high GVWR package or vehicles powered by the 5.4L Modular V-8. While it is often hailed as a light duty version of the Ford F-250/F350s Sterling 10.50" differential, the Sterling is a heavy duty, full floating axle. Limited slip and electronic locking versions of the differential have been manufactured. A 9.75HD rear axle has been offered in the Ford F-150 for select high capacity configurations; it carries a maximum 4,800 lbs GAWR.

Ford 9.75" Axle Specs

Manufacturer:

Ford Motor Company

Production Plant:

Sterling Axle Plant, Sterling Heights, MI

Applications:

• 1997 + Ford F-150

• 1998 - 1999 Ford F-250LD (light duty, NOT Super Duty)

• 1999 - 2004 Ford F-150 SVT Lightning

• 1997 - 2006 Ford Expedition

• 1997 - 2005 Lincoln Navigator

• 1999 - 2010 Ford E-Series vans

Full/Semi Float:

Semi floating

Axle Type:

Rear differential, mostly solid axle but an independent rear suspension (IRS) version was used in select SUVs beginning in 2003

GAWR:

Maximum 4,500 - 4,800 lbs (9.75HD version)

Ring Gear:

9.75 in

Pinion:

1.970" shaft dia

Axle Shafts:

34 spline, 1.37" dia (1.29" min axle shaft dia)

Fluid Type*:

75W-140 synthetic gear oil

Fluid Capacity**:

2.75 qts, 2.6L, 5.5 pints

Identification:

12 bolt differential cover, shape similar to Sterling 10.25"/10.50"
Ford 9.75 inch differential bolt pattern

*Recommended fluid type and fluid capacity may vary by model year and application - always refer to your vehicle's owner manual for specifications specific to your application.
**Always fill axle until fluid level reaches the bottom of the fill plug hole.