Our new performance lower arms replace the stock length lowers and gives you the ability to either run a secondary bypass shock for increased control or an air bump stop for bottoming resistance. We’ve developed and tested a FOX 2.5 bypass shock specifically for these arms with a custom bypass tube configuration. When designing these arms, we set them up for maximum useable wheel travel along with the correct shock motion ratio geometry. They are to be used with 2.5/3.0 coilovers that use a uniball/spherical bearing in the lower rod. They do NOT work with OEM style struts that use a bushing and sleeve in the lower mount.
CAD/CAM engineered, the arm is considerably stronger than the sheet metal stock arm and was designed to maximize ground clearance and off-road performance. It has internal gusseting and pivots on FK 1″ uniballs at the frame rather than cheap rubber or polyurethane bushings that constantly bind and flex under braking. Uniballs allow for zero binding when the suspension cycles up and down and has zero flex under braking so your geometry and alignment is always consistent. With Toyota trucks being aligned by the lower arm, a uniball setup also allows for a bind free adjustment and you’re able to torque all the bolts without putting it into a bind. Since the uniball spacers are 1.50” in diameter, you have better clamping force in the frame mounts due to the increased surface area which keeps the holes from ovaling out over time unlike a small diameter sleeve used in a bushing. This also keeps the alignment cams from loosening up from off-road use.
We eliminate the weaker lower ball-joint with an FK 1.00″ uniball at the spindle for maximum strength and articulation. No modification to the spindle taper is necessary as we use machined heat-treated stainless-steel mis-alignment spacers that adapt the uniball to the tapered ball-joint spindle bore.
To attach the spindle to the uniball we use a Mil-Spec 21250 NAS 12-point aircraft bolt. These bolts are rated 180,000 psi minimum tensile strength and 108,000 psi minimum shear strength. A stronger or higher quality bolt does not exist, hence why the Military, NASA and Aircraft companies use these. They have a specific shoulder/grip length and the head design yields higher tensile and shear strengths compared to any Grade 8, 9 or 12.9 bolt. They are made to the highest quality control standards out there. These bolts alone cost $60 each …. You truly get what you pay for.
The arms are CAD designed, laser cut, CNC formed, MIG welded, powder coated Camburg gray and are ready to install with all the necessary hardware included.These are by far the strongest stock length aftermarket arms out on the market. Combine these with our performance spindles for the ultimate setup.
When setting up your truck to run a bypass shock you will also need our weld-on bypass mount kit for the frame side and you will need to remove the factory rubber bump stop mount on the frame.
With the bump stop version arms you can run the factory rubber bump stop or step up to a FOX/King 2.0 x 2.5 or 2.5 x 2.5 air bump by removing the factory bump stop mount on the frame and welding on bump cans with some minor fabrication.
- Also fits ’10-19 4-Runners & 10-14 FJ’s (non KDSS equipped models)