Rough Country Square U-Bolt Kit for 2.5" Axles — 2.5" x 8.5" Inside, 9/16" Thread, Set of 4, Black e-coat

Rough Country's Universal Square U‑Bolt Kit is a heavy‑duty set of four square U‑bolts designed to secure 2.5" axle tubes, with 9/16" threads and a black e‑coated finish for long‑lasting corrosion resistance.

If your suspension hardware is corroded, bent, or you’re installing lift blocks, this universal kit provides stout replacement U‑bolts that match many common truck and trailer configurations. Each U‑bolt is formed from high‑strength steel and finished with a black e‑coat to defend against road salt, moisture, and grime. The set arrives complete with nuts and washers so you can finish an axle rebuild or lift installation without sourcing additional parts.

Will these U‑bolts fit my axle and lift setup?

These square U‑bolts have an inside width of 2.5 inches and an inside length of 8.5 inches, making them suitable for many leaf‑spring suspension and lift block arrangements that use that axle tube diameter. The 9/16" threaded ends accept common grade nuts and hardware for strong clamping force. Measure your axle tube and required leg length to confirm fit before ordering.

• Inside dimensions: 2.5" W x 8.5" L
• Thread size: 9/16" suitable for standard hex nuts
• Square leg shape for secure clamp against leaf springs or blocks
• Set includes 4 U‑bolts plus nuts and washers for a complete install

How durable are these U‑bolts for daily driving and off‑road use?

Constructed from high‑strength steel, these U‑bolts are engineered to resist bending and maintain clamping pressure under load. The black e‑coated finish adds a protective layer that slows rusting and chemical attack from road salt and mud. For extreme off‑road or heavy towing cycles, regular inspection and proper torqueing are still recommended.

• High‑strength steel core for load bearing and reliability
• Black e‑coat finish defends against corrosion and surface wear
• Designed to hold leaf springs and blocks securely under stress
• Works well for both street driving and light to moderate off‑road use

What comes in the kit and is installation straightforward?

The kit ships with four square U‑bolts, matching nuts, and washers so you have everything necessary to clamp axle to spring pack or lift block. Installation is typical for U‑bolt replacement—raise and support the vehicle, remove old hardware, align springs/blocks, fit U‑bolts, then torque to the vehicle or component manufacturer’s specification. No specialty parts are required beyond standard hand tools and a torque wrench.

• Included: 4 square U‑bolts with nuts and washers—ready to install
• Requires: jack stands, basic hand tools, torque wrench for final tightening
• Installation tip: tighten gradually and re‑check torque after initial road use
• Compatible with many common axle, spring, and block combinations

Who is this for? This Rough Country Universal Square U‑Bolt Kit is aimed at truck owners, trailer builders, and DIY mechanics who need reliable replacement hardware for axle clamps, leaf‑spring setups, or lift block installs. If you want heavy‑duty U‑bolts that arrive with the nuts and washers included and offer extra corrosion protection, this set is a practical, ready‑to‑install option for routine suspension work and moderate off‑road use.