Grand National Rear End, 60 Inch, 5 on 4-3/4, Compatible with GM Metric

Direct bolt in for GM Metric G-body race car chassis. IMCA approved housing for Stock Car classes and other sanctioning bodies that require a single hole mount for trailing arms. Machined full floating axle housing design with fully welded 3-inch axle tubes. Pre-fitted upper and lower control arm mounts and disc brake caliper brackets. Fully machined 2.5-inch axle tube ends for fitting Grand National hubs. Lightweight steel hubs use 2.5-inch ID tapered bearings for increased loads. Axle housing features centered pinion design for maximum driveshaft clearance. Available in 58 and 60 inch wheel flange to wheel flange measurements. Floating hubs are offered in 5x5 and 5x4.75 wheel bolt patterns with 5/8-11 studs. Includes 31 spline solid axles that fit popular differentials and spools. Housing includes oversized fill and drain plugs for easy fluid changes. NPT threaded axle vent located on main housing. 24-spline drive plates with aluminum axle caps allow easy axle removal. 11.75-inch disc brake rotors, bearings, seals, and hardware included. Only needs disc brake calipers, spring perches, and third member to complete. Upgrade To a Full Floater Rear End for Increased Strength and Safety The full floating rear axle has been around for decades. Primarily designed for heavy duty truck use, it was found to be a great solution for circle track racing and has been a race-spec axle housing used in all levels of circle track racing ever since. Today you’ll find high horsepower street cars that see extreme cornering g-forces (auto crossing, road racing, etc.) using full floater rear end setups as well. So why the change to a full floating axle from the more conventional semi-floating axle found under just about every rear drive production car made in the last century? It’s easy really when you compare the differences between full floating vs semi floating axle assemblies. In a semi-floating axle, such as the popular GM 10 and 12 bolt rears, or Ford’s 7.5- and 8.8-inch rear ends, the axle assembly is retained by a C-clip at the differential end and rides on a single bearing seated in the end of the axle tube. The full weight of the vehicle rides on this single small bearing while the differential end of the axle shaft floats in the differential or spool, hence the “semi” floating term. This design puts a lot of stress on the axle bearings and seals and it is not uncommon to bend axle flanges in hard cornering or chew up a bearing (which ruins the axle). Additionally, if the C-clip should fail from side loading, or the axle break from excessive torque, the broken axle with wheel and tire assembly can exit the axle housing causing extensive damage and loss of control of the vehicle. While a bolt-in axle like the popular Ford 9-inch is an improvement, axle flange stress can still lead to bending or breaking right at the bearing in hard cornering. Meanwhile, the full floating axle uses a hub that rides on a pair of large bearings on the end of the axle tube itself (similar to your front disc brake rotor and spindle). This allows the full weight of the vehicle, as well as all acceleration, braking, and cornering forces to move through the axle housing itself. Due to the dual bearing hub on the end of the axle housing the axle itself “floats between the differential or spool and a splined drive plate that mounts between the hub and the wheel (engaged via the wheel studs), thus the “full floater rear end.” If an axle should break in a full floating rear axle there is zero chance of losing a wheel and tire assembly. Furthermore, due to the fixed hub location disc brake pad knock back (a common issue on semi-floating axles where hard cornering pushes the caliper pistons into the caliper) is eliminated. This provides constant and firm brake pedal application no matter the cornering forces. Hit our Toolbox article on full floater rear axles for more details