Toyota Knuckle Ball Seal

Toyota Heavy Duty Knuckle Ball Wiper Seal System

Part # SKY-137301
Precision Parts / Proven Performance

Upgrade the sealing system on your Toyota solid front axle with the Sky’s Offroad Design Heavy Duty Knuckle Ball Wiper Seal System.

Factory-style Toyota knuckle wiper seals are a common maintenance item on older solid-axle trucks. Once the sealing system deteriorates, grease and contamination can begin working their way around the knuckle ball. A greasy buildup or leakage around the inside of the front wheel is one of the most obvious signs that the knuckle seals need attention.

Sky’s system replaces the traditional sealing arrangement with a heavy-duty design built around Ultra High Durometer Polyurethane wiper seals, heavy steel retainers, corrosion-resistant components, and installation-friendly captive hardware.

Heavy Duty Polyurethane Wiper Seals

The heart of the SKY-137301 system is our Ultra High Durometer Polyurethane knuckle ball wiper seal.

These seals are designed to provide improved sealing and substantially longer service life compared with the traditional Toyota-style mesh/felt sealing arrangement.

Each seal is molded with the SKY-137301 part number directly into the component for easy identification.

Heavy Duty 1/8" Steel C-Ring Retainers

The oil-seal retaining C-rings are formed from 1/8-inch-thick steel, providing a strong and rigid retaining surface for the upgraded wiper seals.

The retainers feature a durable black E-coat finish to help resist corrosion, rust, and finish deterioration during long-term service.

Spacer Rings

The system includes precision oil-seal spacer rings designed to work with the upgraded wiper and retaining system.

The spacer rings feature a silver-zinc corrosion-resistant finish for long-lasting service in the demanding environment around the steering knuckle.

Captive-Washer Hardware

Included are 16 hex-head cap screws with captive flat and lock washers.

The captive washer design keeps the hardware together during installation, eliminating the frustration of handling and potentially losing individual small washers while working around the axle housing.

Hardware features a silver-zinc corrosion-resistant finish for extended service life.

Vehicle Fitment

Designed for Toyota 4WD solid-front-axle applications. Based on the solid-axle application information referenced by Go-Parts, this family includes:

• 1979–1985 Toyota Pickup 4WD
• 1984–1985 Toyota 4Runner 4WD
• 1976–1990 Toyota Land Cruiser, including applicable FJ40, FJ60 and FJ62 solid-front-axle models

This system is not intended for Toyota IFS front suspension applications. Go-Parts specifically notes that the 1986-and-later Pickup IFS knuckle arrangement is fundamentally different from the earlier solid-axle design.

Verify axle configuration and application before ordering.

When Should You Service the Knuckle?

Grease or oily buildup around the back of the steering knuckle—or a greasy mess appearing on the inside of the front wheel—is a strong indication that the existing sealing system is no longer doing its job.

Because accessing the wiper seals requires substantial front-axle disassembly, this is also an excellent opportunity to inspect the rest of the knuckle assembly.

Worn trunnion/kingpin bearings, inner axle seals, wheel bearings, races and other internal wear components are common causes of problems attributed to the knuckle assembly. In many cases, the knuckle housing itself is still serviceable and the proper repair is rebuilding the wear components rather than replacing the casting.

Important Installation Note

When performing a complete Toyota knuckle rebuild, kingpin/trunnion bearing preload must be properly set. Knuckle rebuild kits with trunnion bearings available here.

The preload is checked with a spring scale and adjusted using the appropriate bearing shims. Incorrect preload can contribute to steering wobble when too loose, or excessive steering effort and premature bearing wear when too tight. Refer to the appropriate Toyota Factory Service Manual for your specific axle and vehicle before setting preload or torque specifications.

What's Included

One SKY-137301 system includes components for both sides of the front axle:

• 2 × Ultra High Durometer Polyurethane knuckle ball wiper seals
• 4 × Heavy-duty 1/8" steel C-ring retainers
• 2 × Oil-seal spacer rings
• 16 × Hex-head cap screws
• Captive flat and lock washers
• Corrosion-resistant coated components

Sky’s Offroad Design — Precision Parts / Proven Performance

For the technical background on the Toyota solid-axle knuckle and rebuild process, the Go-Parts reference used here is available at Go-Parts Toyota Solid Axle Steering Knuckle Guide.