Floater axles
Race Products stock a large range of Australian-made floater axles in both 4340 chromoly and 300M-VAR steel. All manufactured right here in our Brisbane facility.
In a full floating rear end, the axle does one job: transmit torque from the diff to the wheel. The hub, bearings and housing carry the weight of the car, handle cornering and braking loads, and locate the wheel. The axle just drives. It floats in the housing, splined at both ends, carrying nothing but twist, which is where the name comes from.
Every axle we make is designed and machined in-house from billet material, heat treated, shot peened, then straightened to a runout tolerance tighter than the big name brands. Peening hammers the surface into compression, so fatigue cracks struggle to get started where an axle works hardest: the spline roots and the neck.
For most builds, 4340 chromoly is all the axle you’ll ever need. It’s our most popular axle material. 300M is a vanadium-modified 4340 that’s heat treated to a substantially higher tensile and yield strength, with better fatigue resistance, so the same diameter and spline can carry more torque, more often, before it winds up or fatigues. If you’re at the upper end of what a spline count can handle, running slicks and a transbrake, or bouncing off kerbs or ruts, step up to 300M for the extra margin.
- True involute hobbed splines for uniform load distribution and proper mating with spools, LSDs and OEM components
- Necked down from the spline so wind-up is spread over a longer length rather than concentrated at one point
- Heat treated, shot peened and straightened to a tight runout tolerance
- Same spline count both ends
- Circlip included
- Batch marked for full material traceability
Which spline?
The axle spline end needs to match what it drives: the drive flange on a floater kit, and the spool, LSD or side gears in the centre. The tooth count has to match, and so does the pressure angle. Ours are hobbed 24/48 DP, 45° in 28, 30, 31 and 40 spline, and 30° in 35. A 30° and a 45° spline with the same count look similar but are not the same, and will not go together.
| Spline | OD | Fits | Not the same as |
|---|---|---|---|
| 28 | Ø30.7 | Ford 9″ small bearing, Ford 8″, Ford 8.8″ 28-spline, GM 10-bolt, BorgWarner 28 (Falcon EB–AU, BA–BF non-turbo, Commodore VN–VZ V6) | Mazda RX-4 / RX-5 13B, Honda S2000 (both Ø29) |
| 30 | Ø32.8 | Toyota Hilux / LandCruiser, GM 12-bolt, GM 8.5″ 10-bolt | BorgWarner M86 (Falcon BA–FG, Crewman), Dana 30/35/44, Chrysler 8¾″ (all 30° PA). GM 14-bolt (bigger shaft) |
| 31 | Ø33.8 | Ford 9″ big bearing, Ford 8.8″ 31-spline, BorgWarner 31 upgrade | Nissan Patrol H233 (Ø32) |
| 35 | Ø38.1 | Dana 60/70, aftermarket Ford 9″ big-spline (30° PA) | Ford 10.25″/10.5″ 35-spline. Mark Williams MW spline spools and centres (45° PA); their std/Dana-style 35 spline fits |
| 40 | Ø43.4 | Aftermarket Ford 9″ / Dana 60 big-spline | — |
Not sure? Count the teeth on your old axle, or on the parts it drives (the drive flange at the wheel end, the spool, LSD or side gears in the centre), measure the OD, and contact us to confirm.
Stocked range
Available spline, length and material combinations. Contact us to discuss the best option for your application, or to enquire about custom splined floater axles.
Gun drilled
40 spline 300M is also available gun drilled. Gun drilling bores a 7/8″ hole down the centre of the axle, saving about 300 g per 100 mm. You are removing material though, so you do give up some torsional stiffness. Same fit, same spline, same circlip. Custom made to your exact length, so allow 8 to 10 weeks. Order online