U-bolts are essential for securing leaf springs to your vehicle's axle, ensuring ride stability and load-carrying capacity. Selecting the correct U-bolt is crucial for safety and proper vehicle function, as an ill-fitting or low-quality part can compromise performance and even lead to component failure.
- Package contents: The package includes 4 sets M6 round U-bolts (including round bolts, nuts, washers and frame plates), the total length of u-bolts is 25 mm(1 inch), the inner width is 70 mm(2-3/4 inch).
- Material: This round bend U clamp is made of steel and galvanized surface, not easy to deformation, corrosion resistance and rust resistance, can be used outdoors for a long time.
- Load capacity: U-shaped bolt of steel structure, using bending molding processing technology, high hardness, good tensile strength, high bearing capacity, can be used to fix pipes, plates, practicability.
- Wide application: M6 U-bolt is used to fix or attach the locking parts to the pipe, wood, and more, suitable for the connection of ships, trailers, industrial steel structure pipes.
- U-Bolts SIZE：the square U bolts measures about M8 in diameter, about 52mm/2 inch in I.D width and about 100mm/3.9 inch in O.D length, The OD size of your project can be used to match the suitable U-bolt ID before ordering, please confirm the size before
- What's included : you will get 4 pcs of U bolts 2 inch wide, plus 4 pcs of frame plates，8 pcs of washer and 8 pcs of nuts, 1 Pcs wrench，a complete set can meet your use and replacement
- Materials : U-Bolts Made of 304 stainless steel, strong, have great performance in rust resistance, moisture resistance, and corrosion resistance
- Broad utilization : the square U bolt clamp is practical and widely applied in various fields such as industry, manufacturing, maintenance, automotive industry, garment production, etc., which are ideal for fastening pipes, wood, trailers and more
- U-Bolts SIZE：the U bolts measures about M8 in diameter, about 40mm/1.5 inch in I.D width and about 90mm/3.5 inch in O.D length, The OD size of your project can be used to match the suitable U-bolt ID before ordering, please confirm the size before
- What's included : you will get 4 pcs of U bolts 40mm wide, plus 4 pcs of frame plates，8 pcs of flat washer，8 pcs of lock washer and 8 pcs of nuts, 1 Pcs wrench，a complete set can meet your use and replacement
- Materials : U-Bolts Made of 304 stainless steel, strong, have great performance in rust resistance, moisture resistance, and corrosion resistance
- Broad utilization : the U bolt clamp is practical and widely applied in various fields such as industry, manufacturing, maintenance, automotive industry, garment production, etc., which are ideal for fastening pipes, wood, cars, sailboat trailers and more
- Heavy Load Fastening Kit: Includes 4 sets of M6 U bolts with frame plates and nuts for applications requiring stronger support
- Designed for Large Pipes and Structures: 27mm x 70mm accommodates larger diameter pipes, thick bars and structural mounting points
- Suitable for High Demand Environments: Performs well in industrial setups, outdoor installations and equipment mounting where stability is critical
- Reliable Under Vibration: Maintains secure fastening in moving or high vibration conditions such as trailers and machinery
- 4 pack of Square U-Bolt: 1/2 x 3-1/16 x 4-5/16 inch and hardware for 3x3 cross member
- U-Bolts made from heavy-duty, durable galvanized steel
- Zinc coated to prevent rusting and suitable for marine trailers and motor boats in saltwater, freshwater, coastal conditions, and utility/land trailers in icy conditions
- Includes: (4) square u-bolts, (8) hex nuts, (8) flat washers, (8) lock washers
- Size：M8 U-Bolt with inner dimensions of 1-1/2"W x 3-1/2"L and thread length of 1-3/4". Please confirm the required size before ordering to avoid delays due to mismatched specifications.
- What's Included：4 x U Bolts 1-1/2 Inch Wide, 4 x frame plates, 8 x flat washers, 8 x lock washer and 8 x nuts, 1 x wrench. All accessories are complete, no extra purchases needed, and ready for installation right out of the box.
- Materials：U-Bolts Made of 304 stainless steel, strong, have great performance in rust resistance, moisture resistance, and corrosion resistance.
- Wide Applications：Suitable for securing pipes, wood and steel. Compatible with RV bumpers, boats, outdoor brackets, industrial equipment and more.
- Size：M10 Square U-Bolt with inner dimensions of 1-1/2"W x 3-3/8"L and thread length of 2-1/2". Please confirm the required size before ordering to avoid delays due to mismatched specifications
- What's Included：2 x U Bolts 1-1/2 Inch Wide, 2 x frame plates, 4 x flat washers, 4 x lock washer and 4 x nuts, 1 x wrench. All accessories are complete, no extra purchases needed, and ready for installation right out of the box
- Materials：U-Bolts Made of 304 stainless steel, strong, have great performance in rust resistance, moisture resistance, and corrosion resistance
- Wide Applications：Suitable for securing pipes, wood and steel. Compatible with RV bumpers, boats, outdoor brackets, industrial equipment and more
- Max Safe Load: 3500 lbs.
- Size: 3/8" Dia, 2-1/2" Thread Length, more sizes refers to pictures.
- Easy to Install: Comes with all hardware, easy to install.
- Durable: Made of marine stainless steel, resistant to rust and corrosion.
- Feature: The square U bolts threads are 3/8 " in diameter, 3" in width, and 7 "in length, suitable for 3 x 3" square objects, and can be used to secure pipes, plates, and planks; Please check the dimensions before ordering
- Premium Quality: Made of stainless steel, these U-bolts have excellent load-bearing, strong and durable, reliable and durable, rust resistant and corrosion resistant, also suitable for rainy and humid environment
- U Shape Design: This design can lock the connector fixed on the square object, will not be locked because the surface area of the locked object contact is too small and cause to locking failure; You can also cut square bolts in half to use as a 90-degree...
- Complete Set: Includes 4 U bolts, 4 frame plates and 8 nuts to meet your use needs, the attached nuts and frame plates are a good complement to make the installation process simple and clear; Use lubricants to prevent wear when installing
- Size：M10 Square U-Bolt with inner dimensions of 4"W x 6"L and thread length of 3". Please confirm the required size before ordering to avoid delays due to mismatched specifications
- What's Included：2 x U Bolts 4 Inch Wide, 2 x frame plates, 4 x flat washers, 4 x lock washer and 4 x nuts, 1 x wrench. All accessories are complete, no extra purchases needed, and ready for installation right out of the box
- Materials：U-Bolts Made of 304 stainless steel, strong, have great performance in rust resistance, moisture resistance, and corrosion resistance
- Wide Applications：Suitable for securing pipes, wood and steel. Compatible with RV bumpers, boats, outdoor brackets, industrial equipment and more
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Last update on 2026-10-17 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best U-Bolts
Understanding U-Bolt Types
U-bolts come in various shapes and sizes to accommodate different axle and spring configurations. The most common types include round U-bolts, which have a curved bend, and square U-bolts, featuring a sharper, 90-degree bend. There are also 'read-eye' or 'ribbed' U-bolts, which have specific features for enhanced grip. Knowing the shape of your existing U-bolts or the required profile for your vehicle is the first step in selection.
Key Measurement Considerations
Accurate measurements are paramount when purchasing U-bolts. You'll need to determine the inside width (the distance between the legs) and the inside length (from the bottom of the bend to the top of the legs). Additionally, note the diameter of the U-bolt material itself, often specified in fractions of an inch. Always double-check these measurements against your vehicle's specifications or the old parts before ordering.
Material and Finish
U-bolts are typically made from high-strength steel to withstand significant stress and vibration. Look for options made from hardened steel for maximum durability. The finish is also important for corrosion resistance. Common finishes include zinc plating, black oxide, or raw steel. Zinc plating offers good protection against rust in most environments, while black oxide provides a durable, non-reflective finish. For heavily exposed or corrosive conditions, consider stainless steel options.
Hardware and Kits
U-bolts are usually sold individually or as part of a kit. Kits often include the necessary nuts and washers, which are essential for proper installation and load distribution. Ensure that any included hardware is also made of high-quality materials that match or exceed the strength of the U-bolt. If buying U-bolts individually, confirm you have the correct size and type of nuts and washers separately.
