Aftermarket 8.8 Rear End – When your supercharged, air-to-water intercooled Duramax project with an Allison transmission and Roadster Shop chassis isn’t unique enough, you enlist the help of Strange Engineering for a one-of-a-kind rear axle. As unbreakable as it is exclusive, the 9-inch hybrid rear axle designed for Banks’ LokJaw project uses custom spindles and features 35-spline chrome axles, but features a late-model GM HD factory bolt pattern. Inside the pumpkin you’ll find an EatonTruetrac limited-slip differential and a 3.89:1 ring and pinion from US Gear. It’s all part of Banks’ plan to make sure their boxed ’66 C20 can handle the four-figure torque numbers the blown L5P Duramax will produce.
For several years now, 9-inch rears have been participating in diesel drag racing with great success – so there’s no reason why one shouldn’t be enough on the street. In addition to being very durable, they save weight in what is usually a fairly heavy, ¾-ton or larger overall package. So without sacrificing strength, the guys at Banks cut weight and got the 180mm x 8 bolt pattern they were looking for. Using the same materials and designs it implements in its axles designed for 3,000 to 4,000 hp. Pro Mods, Strange has created what is probably the most solid 9-inch you’ll ever find under a pickup. You can read all about it below.
Aftermarket 8.8 Rear End
In keeping with the heavy-duty Duramax theme, the guys at Banks decided to go with an 8-tooth axle very early in the LokJaw planning process. However, the truck’s untrimmed curb weight was rightly highlighted by Gale Banks when the crew discussed which route to take – which meant the iconic Ford 9-inch was on the table. And who better to build them a bulletproof 9-incher than a company that’s been doing it for six decades? From the start, the folks at Strange Engineering offered a hybrid-style full-float axle that uses the same chrome float spindles you’d find on a 3000 to 4000hp Pro Mod.
Demolition Derby Rear Ends
Strange’s full-floating design positions the floating spindle inside the axle housing tube so that all torsional loads resulting from torque are absorbed by the outside of the axle tubes. Here you can see the Strange-made drive hub that the wheel will attach to. A drive plate on the outside will connect to the actual half axle.
For maximum torsional strength, Strange wasted no time throwing its 35-spline HyTuf axles into the build. These ultra-strong axles are forged from low-carbon, high-manganese, high-nickel, and high-molybdenum steel, with most of the machining done before the heat treatment process that each unit goes through. This results in a consistent depth of heat treatment and ultimately a stronger axle.
Built as a hybrid by the folks at Strange, it’s all factory 11-new GM HD on the outside, but completely custom on the inside. This allows the guys at Banks to run an 8x180mm GM bolt-on pattern and the corresponding late-model brakes that go along with it, while taking advantage of Strange’s nearly unbreakable 9-inch parts on the inside.
The legendary Eaton TrueTrac limited-slip differential works with the 35-spline axles. This is the quintessential limited slip differential in the automotive world, thanks to its helical gear design that works flawlessly. Fully mechanical, TrueTrac runs smoothly, quietly and acts as an open differential when not needed – making it ideal for street use. This particular TrueTrac 5-gear requires a replacement third member case, which Strange had no problem supplying. As for the ring and pinion, the 3.89:1 axle ratio gets a nod, with the kit coming from US Gear.
Dodge Leaf Spring Shackle Kit (2 Shackles), Rear Of Rear, 5/8
Post-transmission power transfer is resumed here through the use of one of Strange Engineering’s chromolet yokes. We can only assume this is the version that features a 1480 series U-joint. Also note the billet aluminum gear carrier and hollow iron case. Strange’s take on the 9-inch housing is 8 to 10 percent stronger than stock and integrates seamlessly with aftermarket gear mounts. The axle tubes are 3″ in diameter and made from ¼” wall, DOM tubing. It may not be the AAM 1150, but it is lighter and much stronger. With diesel fuel? You bet.
To keep the Strange rear axle centered under the LokJaw at all times, the Roadster Shop added a fully adjustable Watt linkage system. Given the amount of travel that will be available via air travel, this proven, old way of doing things will prevent the axle from moving to one side or the other. We’ll bring you all the details on the Roadster Shop chassis soon.