Signature Series Front 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 Front Housing. From knuckles 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 inner knuckles, but we're including full armor services as well such as gussets and skid plates.

To order, pick your housing, knuckles, gussets, and caliper mounts. Then enter in your wheel mount surface (WMS), housing offset (Af), and Pinion & Caster Angles (in degrees). All Spider 9 Signature Series Front Housings come standard with tig welded 4130 heat-treated skid plates and include a non-welded small fill cap assembly (3-1/2" housings) or a large fill cap assembly (4" housings). 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).
$4,024.00 – $7,141.00
Made to Order
Model No:

Housing: Pick from three Spider 9 housing options -- Ultimate 3-1/2", Pro Series 3-1/2", or a Pro Series 4".

Knuckles: Pick from Ultimate and Pro Series Knuckles. Pro Series Knuckles come with a non-steering arm option and welded steering arm options for low, medium, and high steering heights.

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

Caliper Mounts: Pick from three caliper mount options -- No, Yes (Welded, 13.5" Rotor), or Yes (Welded, 14.0" Rotor). Our caliper mounts are constructed of .375 thick laser cut plate and are tig welded, at a 45 degree angle, to the outer knuckle. Designed specifically for the Wilwood 5.25" lug mount caliper series.

WMS, Af, and Pinion & Caster Angle: Provide your Wheel Mount Surface (WMS), Pinion Location (Af), and Pinion & Caster Angles (in degrees) as shown in the drawing below. WMS is measured from brake hat to brake hat. WMS can range from 60 to 76", Af can range from 22" to 45".



Knuckles are press-fit, aligned precisely to your specifications, and finished with an external 2-pass & internal 1-pass tig weld. Industry-leading quality with none of the guesswork.

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 Knuckles with our 4130 box style gussets. Laser-cut, CNC formed, tig welded, with optional heat treating, gussets never looked better.

Steering Arms

Pro Series Knuckles come with 4130 tig-welded steering arm options for low, medium, and high steering arm heights. There's a perfect steering arm for every build.
Steering Arms