Service Kits

Driveline and axle service kits bundle the bearings, seals, snap rings, and hardware you need to properly rebuild a worn component - saving you from sourcing a dozen individual parts across multiple orders. This collection covers the full range of driveline service work: wheel bearing and hub repairs, CV joint rebuilds, differential bearing and seal replacement, U-joint strap and U-bolt kits, locking hub service, and Double Cardan CV ball seat repairs. Most wheel bearing kits are vehicle-specific and include pre-matched bearing races and seals sized to OEM tolerances - always verify axle shaft diameter and hub bore specs before ordering. For differential kits, confirm ring gear size and axle model (Dana 44, 8.8, etc.). OEM-spec kits from brands like Timken or SKF use consistent bearing grades and seal materials; budget kits may use lower ABEC-rated bearings that wear faster under load or off-road use.

Signs you need replacement

• Humming, growling, or grinding noise that changes pitch with vehicle speed - this typically indicates worn or pitted wheel bearing races. The noise often intensifies when weight shifts during a lane change, pointing to which side is failing.
• Clicking or popping on tight turns, especially under acceleration - a classic sign of a worn CV joint. If the grease boot has been torn or leaking, the joint has likely been running dry and needs a full rebuild kit or replacement.
• Vibration through the floor or drivetrain clunk when shifting between drive and reverse - worn U-joints or a failing drive shaft flex joint. Inspect for rust, pitting, or dry needle bearings in the U-joint caps.
• Gear oil leaking from the differential housing or axle tube - failed pinion seals or worn axle bearing seals allow lubricant to escape, which can lead to accelerated ring-and-pinion wear if not addressed. A differential bearing and seal kit handles this in one service.
• Looseness or wobble felt at the wheel with no play in the tie rod or ball joints - worn hub assembly bearings or a failed hub repair kit component. Jack the wheel, grab it at 12 and 6 o'clock, and check for radial play.
• 4WD engagement that's rough, delayed, or won't release on a manual locking hub - the locking hub internals are worn or corroded. A locking hub service kit typically includes the spring, detent ball, and internal gear components needed for a full rebuild.

Frequently asked questions

• How often should wheel bearings and differential seals be serviced? Wheel bearings on non-sealed hub assemblies (common on older trucks and 4WD front axles) should be cleaned, inspected, and repacked every 30,000–50,000 miles. Differential seals typically last 60,000–100,000 miles but should be inspected any time you service the differential fluid or notice oil weeping around the axle tube or pinion flange.
• Are aftermarket bearing kits as reliable as OEM for daily drivers and towing applications? Timken, SKF, and National are the most common OEM suppliers and their retail kits are direct equivalents to what came on your vehicle. Lesser-known imports may meet dimensional specs but often use lower-grade bearing steel - a real concern for tow vehicles or trucks that see heavy axle loads. Stick with Timken or SKF if you're routinely over 5,000 lbs GVW.
• What else should I replace while I have the hub or differential apart? If you're replacing wheel bearings, install new axle seals and hub seals at the same time - they're cheap and already exposed. On a differential job, replace the pinion seal, carrier bearing shims if worn, and the differential cover gasket. CV joint work is a good time to replace both inner and outer boots even if only one is torn, since labor is already done.