Our test mule was a '97 F-150 with the 5.4L V-8, 3.55:1 gears, and an open diff. With nearly stock-size tires, the owner opted to keep the stock gears, but he wanted a very streetable traction aid. Detroit's Truetrac gear-type limited-slip filled the bill in that department, and the 9.75 is a brand-new application. Eaton/Detroit Locker also makes a Detroit Locker available for the 9.75.
Being known as a bit of a lead foot, and a guy who tows trailers and does a bit of mild 'wheeling, our owner wanted some extra beef. To that end, we installed a pair of stout Yukon 1541H alloy axleshafts, with new wheel bearings and seals, from Randy's Ring & Pinion. Randy's also supplied a crush-sleeve eliminator kit.
The final building block to the 9.75 was TA Performance's diff cover/girdle. This heavy-duty 356 aircraft alloy, T-6 heat-treated aluminum cover does several things. The first is structural support for the housing in general, and carrier bearings in particular, via a pair of externally supported load bolts. Billet carrier caps are sometimes used in the same way, but it's been learned by race teams that a cap/girdle does the same thing and is easier to fit with no special machining needed.
It took a while for the aftermarket to step up to the 9.75, but in looking at its attributes, it's no wonder the Lightning boys with the older trucks and 8.8 axles are upgrading to the 9.75. The 9.75 could make a nice swap for any 1/2-ton-rated 4x4 rig, Ford or not. It has the advantage of having that "Three Bears" quality of being just right in the size and strength department to make a worthwhile improvement over the weaker 1/2-ton axles. Considering that used semi-floating Dana 60s are getting scarce, the 9.75 may become the new "junkyard D60" of the new millennium.
6. The Yukon crush-sleeve eliminator kit (the pinion seal is not included) replaces the pi
7. University of Northwestern Ohio Instructor Dave McPherson demonstrates the proper use o
8. The 9.75 is a C-clip axle. The Truetrac has a solid spacer installed between the two sh
9. The old crush sleeve (short style shown) provides a starting point for making up the Yu
...Add or remove shims to obtain the correct 15- to 19-in-lb preload with new bearings, or
10. TA Performance offers the option of aircraft-grade studs, nuts, and washers for the ca
11. The TA girdle is torqued to the housing. This is important as the cover actually adds
12. Installing the Yukon shafts is just as easy as the factory shafts. The big thing is to
|Ford 9.75 Semi Float vs Dana 60 Semi Float |
|Axle ||9.75 ||Dana 60 |
|Ring gear dia. ||9.75 ||9.75 |
|Pinion shaft dia. ||1.970 ||1.625 |
|Axleshaft splines/dia. ||34/1.37 ||35/1.50 |
|Axleshaft min. dia. ||1.29 ||1.36 |
|Axle tube dia./wall ||3.25/.180 ||3.12/.250 |
|Output torque max ||6,100 ||5,500 |
|Output torque cont. ||1,500 ||1,500 |
|GAW ||4,500 ||5-5,500 |
|(Measurements in inches and pound-feet)|
|Note: Output torque is rated two ways, as the maximum continuous and the short term maximum. Minimum diameter is usually the minor spline diameter, and that is the case on both these units.|
Randy's Ring & Pinion
University of Northwestern Ohio
16167 N. 81st St.