How To Install A New Rearend - Ford 8.8

We went with a complete 3.55 Motive ring-and-pinion gear set from Strange along with an installation kit with all-new carrier and pinion bearings, crush sleeve, seals, and a new pinion nut.

Installing The Gears
Once we had the leaf-spring pads in place, all that was left to do was install the new gears. We're going to skip over the details of installing the Strange 3.55:1 gears and new bearings in our 8.8 housing, since that information has been covered in the past and the installation is exactly the same as with any other integral housing such as a GM 10- or 12-bolt, or even a Dana 60. Along with the new gears, we also included a Strange installation kit that included all the new bearings as well as pinion seal and pinion nut. The key to setting up any ring-and-pinion is proper pinion depth combined with the right backlash figure to ensure a good pattern. Tim Moore set up our 8.8 Ford rearend using tools from T&D Machine.

Once the spring pads were accurately placed and Moore had double-checked the position and the angle, he tacked the pads in place and then carefully welded the pads with 11/42-inch-long bead welds to minimize heat concentration.

It's All In The Splines
Axle strength can be directly tied to the number of splines on the shaft, when correlated with axleshaft diameter. The weakest link in the stock Ford 8.8 is the 28-spline axles used in the '80s and early '90s Mustangs. We used new 28-spline axles for this rebuild because we decided to retain the production 8.8 Ford Traction-Lok limited slip. But if you're willing to trade a little more coin for more strength, the best move is a set of 31-spline axles. Ford even realized this chink in the 8.8's armor, upgrading to 31-spline axles with the '05 and later Mustangs. Using the stock 28-spline axles also means using the factory C-clip for axle retention. The problem with C-clip axles is that should the axle break anywhere inside the housing, it's free to slide out, doing all sorts of evil things to the sheetmetal.

Randy's Ring & Pinion supplied a 1330-styleU-joint pinion flange to replace the flat flange style used on '80s 5.0 Mustangs. With the engine swap we have planned, now we can have a custom driveshaft made with stronger U-joints to increase the strength.

The best solution is to secure the axle at the end of the housing flange just as the 9-inch axles are retained. It is possible to have a shop remove the stock axlehousing ends and weld on new 9-inch-style ends that not only increase the axle bearing size, but also eliminate the C-clip at the same time. Strange and most other driveline companies offer housing ends, the appropriate-length axles, and bearings to make this work, which also allow you to retain the stock 8.8 drum-brakes backing plate (with a little modification). This is a far better solution than a C-clip eliminator kit, especially if there are 31-spline axles in your future.

Budget 8.8 Build Up
It's pretty easy to rack up over $1,000 in rearend parts if purchasing everything new. So we thought we'd try the low-ball route by pulling as much stuff as possible from the used parts pile. This outline doesn't include brakes, but if you are frugal, you can actually assemble this rearend for less than $400. Of course, we're assuming that the used axles and gears are in decent shape and will survive for a while. Just the price of axles and a good limited slip will bump the cost by $700 or more. With these parts, you have a very durable rearend that will live behind even a big-block, especially with 31-spline axles.