1] Some 19861993 Mustangs had disc brakes. All SVO Mustangs had five-lug disc brakes, then in 1994, most Mustangs had rear disc brakes.

2] On earlier vehicles, the ID tag is bolted to the diff cover, though they are often missing. Ford started phasing out the metal tags in the late ’80s, replacing them with a sticker located on the axletube by the brakes.

3] The axletubes have been known to turn inside the housing, as they’re held into the third member by just two plug welds, seen here. Use nickel rod and weld the tubes all the way around where they enter the housing.

4] Many models included a Traction-Lok limited-slip differential, which can be identified by a large, S-shaped clip pressing against the inside of the side gears. This can be seen only with the cover off; without an ID tag, you can’t spot a TractionLok from the outside.

5] Plastic covers are occasionally found on ’90s Rangers and Explorers.

6] Fox-body 8.8s have coil-spring perches and tabs for the control-arm bushings. Only truck versions have leaf-spring pads.

7] From the factory, 8.8s use 1330- or 1310-series U-joints. This is the companion flange where the yoke bolts. The 1330 has a 3316-inch width for the U-joint, and the 1310 has a 358-inch width. The 1330 is usually found in Ford trucks. The aftermarket sells flanges of various widths for added strength and conversions for Jeeps, all of which fit either the original 1330- or 1310-series universal U-Joints.

8] These rearends generally use a 28-spline pinion yoke, but some trucks use a 30-spline.

9] This is the plug for ABS found on some 8.8s.

10] Most 8.8 axletubes are 3 inches in diameter and very thin. To prevent warping from heat, don’t use a torch and avoid extended use of a die grinder while modifying an 8.8.

11] The 8.8 is cheaper than a 9-inch, and if you add 31-spline axles, it can be as strong as a GM 12-bolt. The pinion-gear shaft diameter is larger than on a 9-inch and the same size as on a Chevy 12-bolt.

12] Ranger and Explorer axles have a 5-on-412-inch bolt pattern. Fox-body axles use a four-lug wheel pattern.

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