Axle Perch Bolt

Axle Perch Bolt

1932–1948 Ford Car, 1939–1948 Mercury, and 1932–1941 Ford Pickup

Within the Brakes & Suspension system, the axle perch bolt is a structural pivot component used on solid front axle applications. This collection covers the Spring Perch Bolt and corresponding Spring Perch Bolt Nut used on 1932–1948 Ford passenger cars, 1939–1948 Mercury models, and 1932–1941 Ford pickups.

On these vehicles, the perch bolt secures the transverse front spring to the axle while also serving as the pivot location for the radius rod or wishbone assembly. It is not simply a fastener. It establishes alignment, controls fore-aft stability of the axle, and directly influences steering feel.

When rebuilding an early Ford front end, correct perch bolt dimensions and thread engagement are critical. Improper hardware at this location introduces wander, inconsistent caster behavior, and premature bushing wear. This category focuses specifically on the hardware that maintains that pivot integrity within the factory-style suspension design.

The perch bolt passes vertically through the axle boss and spring eye, creating the primary spring mounting point on solid axle applications. The lower threaded section secures with a dedicated Spring Perch Bolt Nut, maintaining clamping load and pivot stability.

On 1932–1948 Ford cars, 1939–1948 Mercury, and 1932–1941 pickups, this bolt also serves as the attachment point for the radius rod or wishbone assembly. Any deviation in shoulder diameter, overall length, or thread condition affects how the wishbone seats and pivots.

Common restoration findings include: Worn or galled threads from repeated disassembly, Distorted shanks from decades of load cycling, Mismatched nuts substituted during prior repairs, Elongated axle bosses caused by loose hardware.

Because this bolt controls a suspension pivot, looseness is not cosmetic. It translates directly into steering instability.

During front end service, inspect the spring eye, axle boss, and mating hardware together. Replacing the bolt without evaluating surrounding components can mask deeper wear.

Review the correct Spring Perch Bolt and Nut for your application before final assembly.