Rzeppa Joint

Introduction

In 1998–2011 Ford Rangers, the Rzeppa joint is a specific type of ball-and-socket constant velocity (CV) joint located at the transfer case end of the front driveshaft. It is housed within the “cupped section” of the shaft and is designed to provide smooth power delivery without the vibrations common to traditional universal joints.

Mechanical Design

Six-Ball Configuration: The joint consists of an inner race (attached to the driveshaft splines) and a spherical outer race (the “cup”), with six precision steel balls held between them by a metal cage.

Contaminant Protection: The “cup” serves as the outer housing that is sealed by a rubber boot. This protects the internal precision bearings from road salt, water, and dirt, which is essential for a component that is positioned low and exposed to the elements.

Constant Velocity: Unlike a standard U-joint, which fluctuates in speed as it rotates at an angle, the Rzeppa joint ensures the output speed exactly matches the input speed at all times.

High Articulation: It can handle significant operating angles (typically up to 45–48 degrees) without binding, allowing it to accommodate the movement of the Ranger’s suspension while the front shaft is spinning.

Performance in the Ford Ranger

Vibration Control: Because a Rzeppa joint maintains constant velocity regardless of the angle, it eliminates the harmonic vibrations that occur when the truck’s pinion angle is not perfectly parallel to the transfer case

Sealed System: The joint is packed with high-temperature grease and protected by a rubber boot to keep out dirt and moisture. It is typically a non-greasable, maintenance-free unit until the boot fails.

Common Failure: A clicking or “tinny” clanking sound often indicates the grease has leaked out or the balls have worn grooves into the races.

1998-2011 Ford Ranger Front Driveshaft

Repair and Replacement

If the “cup” is leaking grease or the driveshaft is making a clicking or “cowbell” sound at low speeds, the CV joint is likely failing.

• CV Joint Repair Kit: You can replace just the internal components and boot with a CV Joint Kit for approximately $47–$95.
• Complete Replacement Shaft: Many owners choose to replace the entire front driveshaft for roughly $155–$250 to avoid the labor of rebuilding the joint.
• Off-Road Upgrade: For lifted Rangers, aftermarket companies like Rough Country offer heavy-duty front shafts with upgraded CV joints designed to handle steeper angles.

2019-2025 Ford Ranger (All 4×4 models)

The 2019-2025 Ford Rangers use the Rzeppa Joint in the front driveshaft, and the 2021-2023 Ford Ranger Tremor uses a Rzeppa Joint in the rear driveshaft.

The “Flinging Grease” Issue

Owners have reported seeing grease sprayed across the undercarriage, often mistaken for a transmission or differential leak. The Rzeppa joint is packed with high-velocity grease and sealed by a rubber boot or metal cap. If the boot develops a pinhole leak or the factory clamp is slightly loose, the high rotational speed of the driveshaft centrifugal-forces the grease out, “flinging” it onto the exhaust and floorboards.

Repair vs. Replacement

Dealers often replace the entire driveshaft under warranty because the Rzeppa joint is technically a “non-serviceable” part. However, some owners fix it themselves by repacking it with PTFE lubricant and securing the boot with high-quality clamps.

Commonality

This is a frequent complaint among Tremor owners due to the joint’s specific design on that trim. Some owners eventually swap to a custom one-piece aluminum driveshaft with standard U-joints to avoid the grease and vibration issues entirely.

Ford Ranger Tremor Driveshaft Prone To Damage

The 2021-2023 Ford Ranger Tremor has a Rzeppa Joint in the driveshaft at the rear differential. If you’re off-road and anything should hit the rubber boot and damages it, it will lead to a loss of grease and then wear of the internal balls/races — often showing as clicking, vibration, or clunking. (This is a general CV joint failure mode common across many vehicles.)

What To Do

Inspect the boot regularly. Especially if you drive the truck off-road.

Contact Tom Woods Custom Driveshafts for a replacement. Tom Woods advertises a one-piece driveshaft for the 2019-2013 Ford Ranger, but it is not designed to work with the Tremor because the Tremor has a different mounting flange on the differential because of its Rzeppa Joint. I’ve also heard of them making an adapter to mount a driveshaft to that flange.

I’ve also heard of people replacing the Tremor flange on the differential with the flange from the non-Tremor Ranger (KB3Z-4851-A) and then mounting a normal driveshaft to it (requires (4) M12 X 35MM driveshaft bolts (P/N W710233-S437)). Either a non-Tremor driveshaft or preferably a one-piece shaft such as the one sold by Tom Woods.

WARNING: This methos requires that you get the pinion nut in the exact same place when you reinstall it to keep the pinion in place with the proper pre-load, otherwise you could damage the axle gears.

Related Article

Building A Front Driveshaft For A 1998+ Ford Ranger