MOOG Greaseable Super Strength Universal Joint 377 for Jeep Wrangler — Heavy-Duty, Serviceable U-Joint

MOOG 377 Greaseable Super Strength universal joint is a heavy-duty, serviceable driveshaft U-joint engineered for higher torque applications and long-lasting on-vehicle service.

Designed and tested by MOOG engineers, this Super Strength® universal joint combines cold-forged bearing cups, a carburized steel cross and MOOG's MICRO SHIELD coating to resist corrosion while allowing on-vehicle greasing. It replaces worn or noisy U-joints in compatible Jeep, Dodge and Fargo applications and is built to endure severe duty where extra strength and serviceability matter.

How does the MOOG 377 improve durability under heavy load?

The MOOG 377 is built for higher torque and horsepower environments. Precision forging, case hardening and heat treatment on critical components reduce wear and extend service life under demanding conditions.

• Cold-forged, case-hardened bearing cups for abrasion resistance
• Carburized and heat-processed steel cross for high fatigue strength
• MICRO SHIELD coating for long-term rust and corrosion protection

Can I grease this U-joint while it’s installed on the vehicle?

Yes—MOOG designed the 377 to be greasable so you can top up lubricant without disassembly. The radial bearing cup design spreads grease 360° for even coverage, maintaining smooth operation and prolonging life.

• Grease fitting compatible with standard grease guns
• Radial cup design for complete lubricant distribution
• Nitrile seals retain grease and block dirt ingress

Which vehicles and fitment details should I confirm before buying?

This U-joint covers a range of domestic and some foreign nameplates and specific model years; always verify fit using your vehicle’s year, make, model, engine and trim. Refer to compatibility notes and the confirmed-fit tool on your retailer’s listing before ordering.

• Fits select Jeep, Dodge and Fargo models across listed years
• Check the seller’s confirmed-fit tool and any “i” notes for exceptions
• Measure existing U-joint and compare part specifications when unsure

What protective features keep contaminants out and grease in?

MOOG combined nitrile seals with a durable coating and precise machining to minimize contamination and maximize grease retention. These seals and the coating help the U-joint resist under-vehicle debris and moisture that cause premature failure.

• Nitrile seals for superior grease retention and debris exclusion
• MICRO SHIELD coating reduces corrosion in wet environments
• Precision-ground surfaces to reduce leakage paths and wear

Who is this for: The MOOG 377 greasable Super Strength U-joint is aimed at do-it-yourself mechanics, professional technicians and owners of compatible Jeep, Dodge or Fargo vehicles who need a durable, serviceable driveshaft joint. It’s especially suited to drivers who tow, carry heavy loads or operate in harsh conditions and want a U-joint that can be maintained without removal.