LokJaw wasn’t going to five-lug just because the front suspension package was built that way. To keep the truck 8-lug for strength and appearance, the front end needed a custom spindle that could mount to the Roadster Shop SPEC Series chassis, replicate Wilwood’s pro spindle geometry, and accept GM 8-lug hubs with large Wilwood TX6R brakes. That’s the real engineering problem here: hub pattern, brake package, and suspension geometry all have to agree. The fix was a purpose-built spindle from KibbeTech using Wilwood’s geometry as the baseline. The design uses machined interlocking features, a keyed caliper bracket to help resist brake torque, and TIG-welded chromoly plate where fit and heat control matter. That gives LokJaw the 8-lug front end it needed without giving up the geometry the chassis was designed around.
This episode follows the next major chassis milestone for Lockjaw: getting the truck ready for 3D scanning at Roadster Shop. Before that could happen, the team needed front spindles. The project's suspension and brake package required a custom solution because the goal was to keep the truck eight-lug rather than converting it to a more common five-lug setup.
That requirement affected both the rear and front of the truck. In the rear, Strange Engineering had already combined a full-floating Ford 9-inch rear end with custom axles and flanges that mate to GM 8-by-180 hubs. Up front, the challenge was mounting GM front hubs along with large Wilwood TX6R brakes while still working with the Roadster Shop Spec Series chassis.
Roadster Shop normally supplies its chassis with Wilwood's five-lug Pro Spindle geometry, but Lockjaw needed an eight-lug equivalent that would accept the GM hub and brake hardware. To make that possible, Wilwood shared the geometry of its Pro Spindle with Kibbetech, a shop known for building eight-lug prerunner components. Using that geometry as the baseline, Kibbetech designed a spindle that would bolt to the Roadster Shop chassis while accommodating the GM eight-lug front hubs.
The result was not an off-the-shelf adaptation but a purpose-built spindle assembly that preserved the intended suspension geometry and brake mounting relationships. That was critical because the truck was also using massive Wilwood TX6R calipers, so the spindle had to manage both packaging and structural loads without compromising fitment.
The finished spindle drew immediate admiration because of how much machining and fabrication work went into it. Kibbetech started with a main block and a machined faceplate, cutting keyways into it and machining both sides in separate operations. Additional pieces were then made to key into that faceplate, creating a precisely located multi-piece assembly rather than relying only on bolts and welds for alignment.
One standout detail was the caliper bracket. It included a keyed register feature that locates the bracket mechanically in the spindle assembly. The bolts still clamp it in place, but the keyway helps prevent the bracket from twisting under braking torque. That matters because the caliper is extremely large, and the spindle has to resist the rotational force generated during hard braking.
The assembly also included several pockets machined into the parts to remove unnecessary weight. Even though the spindle is going on a heavy truck, the builder still worked to trim mass where possible without sacrificing strength.
Three of the spindle's pieces were made from chromoly plate, and welding them together was not straightforward. One of the main difficulties came from joining very different material thicknesses, including 1/8-inch plate to 1-inch plate. Those joints were double-passed to ensure proper fusion and strength.
Another especially difficult area was the steering arm section. In the middle of the spindle, material had to be machined away because the unit bearing protruded farther than desired, and the team needed to guarantee clearance so nothing would rub on the back side. After machining, that area was left at roughly 0.020 inch thick. The builder compared it to welding against something as thin as a soup can lid. That meant carefully lap-welding the machined piece to the surrounding structure without blowing through the thin section.
Despite that challenge, the spindle still maintained the necessary clearance for the unit bearing. The fabrication had to balance packaging, strength, and weld quality in a very constrained area.
Compared with one of Kibbetech's larger prerunner uprights, the Lockjaw spindle is much smaller but in some ways more intricate. The larger upright shown for comparison was also double-passed, but its construction involved a different level of complexity. On the Lockjaw spindle, the steering arm and brake mounting features required more detailed fitment work and more carefully integrated machined pieces.
That complexity also affects welding strategy. Rather than welding continuously in one area, the fabricator moves around the part, welding one section and then shifting to another. He might weld slots first, then move to the underside, then return to another pass elsewhere. That approach helps manage heat input and distortion, which is especially important on a compact, highly machined assembly with mixed material thicknesses and tight tolerances.
The conversation then shifted from the part itself to Kibbetech's welding philosophy. The shop is known for being TIG-only, a choice that began simply because the builder preferred TIG welding and did not even own a MIG welder. For high-end truck fabrication, he considers TIG the right process because it offers more precision and control, even though it takes more time.
He also made clear that weld strength is not determined by process alone. A TIG weld can be poor, and a MIG weld can be excellent; much depends on the operator's technique. One criticism he raised is that MIG welds can sometimes look attractive while lacking penetration, which can lead to failure. With TIG, he prefers the ability to control heat more precisely and place material exactly where he wants it.
That precision is especially relevant on a part like this spindle, where the welds are not only structural but also highly visible. The goal is not just to make the part hold together, but to make it represent the builder well while still maintaining integrity.
The episode spends time emphasizing why these welds stand out. TIG welding requires coordinated control of torch heat, pedal input, puddle size, travel speed, and filler rod addition. To produce a uniform bead, each puddle must receive nearly the same amount of filler while the welder continuously balances heat input. That rhythm is difficult to master, and the team notes that many people can produce visually appealing welds that still fail structurally.
That distinction between appearance and integrity is important. Good fabrication requires both. Some old-school production welders focus only on whether a weld holds, regardless of appearance, but on a visible custom component like Lockjaw's spindle, aesthetics matter too. These parts will be seen on the finished truck, so the welds need to look as refined as the engineering behind them.
The builder also reflected on the online welding community that grew around his work. Many younger fabricators tag him in photos of their own TIG welds, often using the same visual style and references he popularized. He described that attention as humbling, though he also noted that giving useful welding advice remotely is difficult because machine settings alone do not guarantee results. Travel speed, material condition, and the way a specific machine behaves all affect the outcome.
While the spindle fabrication was being wrapped up, Lockjaw itself had already been loaded onto a flatbed and sent to Roadster Shop for 3D scanning. The urgency was clear: the new spindles needed to be boxed and shipped quickly because without them the truck was not a roller, only a chassis. The spindle package was therefore a key dependency in moving the project into the next phase.
Soon after, photos arrived from Roadster Shop showing the truck's body being digitally captured. The scan included the dents, rust, and other surface details rather than smoothing them away, preserving the truck's real condition as the basis for future design and fitment work. With the body now scanned, the project was ready for teardown and the next stage of engineering.
The episode closes by previewing the next installment, which shifts focus to Colorado and the specification of a new ATS transmission. That teaser introduces a technical point about the Allison transmission: although the pump can make 300 PSI, only about 160 PSI reaches the clutch packs.