Signature Series Rear Housing

Since 2005, Spider 9 axles have been the builder axle of choice among top rock crawlers and rock racers alike. While still the ultimate builders' axle, we are excited to now offer the Spider 9 Signature Series Rear Housing. From housing ends to armor, take any guesswork out of building your Spider 9 axle by having our professionals do the heavy lifting. We'll take care of not only welding on your housing ends & outboard seals, but we're including full armor services as well such as trussing and skid plates.

To order, pick your housing and housing ends of choice along with your type of truss and fill cap. Then enter in your wheel mount surface (WMS) and housing offset (Ar). All Spider 9 Signature Series Rear Housings come standard with 4130 heat-treated skid plates, outboard seal inserts, and are fully tig welded. Unit Bearings, brakes, and gears sold separately.

Please note, while there will be no change in price, we may require freight shipping for your Signature Series Housing. Please provide a shipping address on checkout that can accept freight shipments (commercial address w/ access to a forklift).
$1,954.00 – $4,659.00
Made to Order
Model No:

Housing & Ends: Pick from three Spider 9 housing options -- Ultimate 3-1/2", Pro Series 3-1/2", or a Pro Series 4". For ends, all housings come with an Ultimate Unit Bearing full floater option with the Pro Series 4" Housing also having a Pro Series Unit Bearing full floater option, tagged the "Big Bearing" option.

Trussing: Pick from three 4130 trussing options -- No, Yes, or Yes (Heat Treated). The Heat Treated option is highly recommended for racing applications. Our box style trussing is constructed of .120 wall laser cut 4130 plate.

Fill Cap: Pick from our Small (Model No. FLA001) or Large (Model No. FLA214) fill caps, along with the option to have the fill cap bung welded in place as shown in the drawing below.

WMS & Ar: Provide your Wheel Mount Surface (WMS) and Pinion Location (Ar) as shown in the drawing below. WMS is measured from brake hat to brake hat. WMS can range from 60 to 76", Ar can range from 29" to 37".


Floater Ends

Floater ends are press-fit, aligned to perfection, and finished with an external 2-pass & internal 1-pass tig weld. Industry-leading quality with none of the guesswork.
Floater Ends

Skid Plate

All Spider 9 Signature Series Housings come standard with tig welded heat treated 4130 skid plates. With unmatched protection, your housings and R&Ps will thank you.
Skid Plate


Protect your Spider 9 Signature Series Housing with our 4130 box style truss. Laser-cut, CNC formed, tig welded, with optional heat treating, trussing never looked better.

Fill Cap

Finish your Spider 9 Signature Series Housing with the Spidertrax fill cap of your choice. From small (1-5/16) to large (2-1/4), there's a perfect fill cap for every build.
Fill Cap