Complete Troxel Trailer Suspension Parts List: What You Need to Know

If you own a trailer equipped with a Troxel suspension system—common on many utility, boat, and horse trailers—understanding the parts list is essential for proper maintenance and repair. Troxel suspension components are known for durability, but like any mechanical system, they wear over time. This guide covers every major part you’ll find in a typical Troxel trailer suspension, from leaf springs to shackle bolts, helping you identify what needs attention and what to order.

Key Components of Troxel Trailer Suspension

1. Leaf Springs

Leaf springs are the backbone of Troxel suspensions. They absorb road shock and support the trailer’s weight. Troxel springs come in various capacities (e.g., 2,000 lb, 3,500 lb, 5,200 lb) and lengths. Common part numbers include 33-3 (for 3,500 lb) and 33-5 (for 5,200 lb). Springs are usually double-eye or slipper-end; Troxel uses double-eye on most models. Replacement springs should match the original load rating and eye-to-eye length.

2. Slipper Springs (Tandem Axle)

On tandem-axle trailers, Troxel often uses slipper springs on the rear hanger. These have a flat end that slides in a bracket rather than a fixed eye. They allow the spring to lengthen under load. Part numbers typically include an “S” suffix, such as 33-5S.

3. Equalizers

Equalizers distribute weight between front and rear axles on tandem trailers. Troxel equalizers are stamped steel with a center pivot bolt and two outer holes for spring eye connections. They come in varying widths (e.g., 11/4 inch or 11/2 inch) to match the spring bushing inner diameter. A common part number is 35-1 for standard applications.

4. U-Bolts

U-bolts secure the leaf springs to the axle. Troxel U-bolts are typically grade 5 or 8 steel, with both ends threaded. They come in diameters (e.g., 7/16 inch, 1/2 inch, 5/8 inch) and lengths to fit different axle tube sizes and spring thicknesses. Always replace U-bolts in pairs to maintain even clamping force.

5. Spring Hangers (Shackle Brackets)

Troxel suspension uses front and rear hangers to attach the springs to the trailer frame. The front hanger is usually a fixed bracket, while the rear hanger is a shackle that allows spring movement. These brackets are heavy-gauge steel and may include a grease zerk for the pivot pin. Part numbers vary by trailer width and frame size.

6. Shackle Plates (Shackle Straps)

Shackle plates connect the spring eye to the rear hanger. They consist of two plates with a pivot bushing and bolt. Troxel shackle plates are often interchangeable with other brands but should be matched to the spring width. Worn shackle bushings cause excessive play and should be replaced as a set.

7. Spring Bushings

Troxel leaf spring bushings are usually bronze or nylon. They press into the spring eyes and provide a pivot surface for the shackle or hanger pins. Over time they wear, causing noise and misalignment. Replacement bushings are available in standard sizes like 5/8 inch inner diameter.

8. Pivot Pins and Bolts

Pivot pins go through the spring bushings and hangers. Troxel uses pins with grease grooves and a grease zerk fitting for maintenance. Bolts are grade 5 or 8 and should be torqued to manufacturer specifications. A typical pin kit includes the pin, washers, and cotter pin.

9. Hardware Kits

Troxel offers hardware kits that include lock nuts, washers, and cotter pins for a complete suspension overhaul. These kits save time and ensure you have the correct fasteners. For example, part number 99-1 is a hardware kit for single-axle trailers.

10. Center Bolts (Spring Center Pins)

Center bolts align the leaf pack and locate the spring on the axle via a hole in the spring seat. They are threaded on the bottom to hold the U-bolt plate. If a center bolt breaks, the spring pack can shift. Replacement center bolts are available in lengths from 1 inch to 2 inches.

11. Spring Seat Pads

Troxel uses steel or rubber spring seat pads between the axle and leaf spring. These prevent metal-on-metal wear and cushion the ride. Some pads have a locating hole for the center bolt. Check for cracks or flattening during inspection.

12. Slipper Spring Bracket (Slider Bracket)

For slipper springs, a slider bracket is used at the rear. It has a smooth surface for the spring end to slide on. Troxel slider brackets are replaceable and should be greased to prevent galling.

How to Identify the Right Troxel Suspension Parts

Check the Trailer VIN or Axle Rating

Troxel parts are often associated with specific axle weights. Look for a tag on the trailer frame or axle tube. Alternatively, measure the spring length, width, and number of leaves. A typical 3,500 lb axled trailer uses 1-3/4 inch wide springs with 4-5 leaves.

Look for Part Numbers on Existing Components

Many Troxel parts have stamped numbers. For example, “33-5” on a spring or “35-1” on an equalizer. Write these down before ordering replacements. If numbers are worn, compare measurements with Troxel catalogs available online.

Match Bushing and Pin Sizes

Troxel uses two common bushing inner diameters: 5/8 inch and 3/4 inch. Measure the pin diameter or the I.D. of the shackle bore. Incorrect sizes cause premature wear.

Common Replacement Scenarios

Worn Springs (Sagging or Broken Leaves)

If the trailer sits low on one side or you see a broken leaf, replace the entire spring pack. Always replace both springs on an axle to maintain balance. Use Troxel brand springs or verified aftermarket equivalents with the same load rating.

Shackle Bushings Worn Out

Symptoms: loose feeling, clunking noise when turning. Replace the bushings and possibly the shackle plates if the bolt holes are elongated. Troxel shackle kits include everything needed.

U-Bolts Stretched or Corroded

U-bolts can stretch over time, especially under heavy loads. Replace them whenever you remove them for spring work. Never reuse old U-bolts. Grade 8 is recommended for heavy trailers.

Equalizer Pivot Bolt Loose or Worn

Equalizers pivot on a heavy bolt. If the bolt hole is oval, the equalizer must be replaced. Tighten the pivot bolt to spec (typically 80-100 ft-lbs on 1/2 inch bolts).

Practical Tips for Maintenance

• Grease all pivot points (shackle pins, equalizer pivot) at least once a season using a lithium-based grease.
• Inspect for rust on spring leaves; surface rust is normal, but deep pitting weakens the spring.
• Check U-bolt torque after the first 50 miles of a new installation and then annually.
• Replace suspension bolts with Torx or hex-head bolts that are easier to tighten with a torque wrench.
• Always use lock nuts (nylock or prevailing torque) on suspension fasteners.

Recommended Parts for a Full Troxel Suspension Overhaul

If you are rebuilding a tired Troxel suspension, consider this minimum parts list:

• Leaf spring pack (left and right)
• U-bolts (4 for tandem, 2 for single axle)
• Shackle kit with bushings, pins, and straps
• Equalizer (if tandem)
• Center bolts
• Spring seat pads
• Grease zerks and grease

For a tandem 3,500 lb trailer, a typical kit includes: 2 x 33-3 springs, 4 x U-bolts (7/16 x 4), 1 x 35-1 equalizer, 2 x shackle kits (SSK-1), and hardware. Always cross-check with your trailer’s specific measurements.

Final Recommendation

When replacing Troxel suspension parts, stick with genuine Troxel components or high-quality aftermarket replacements that match OEM specifications. Avoid cheap unbranded parts—they often have substandard steel and short life. Measure twice, order once. If you are unsure, consult a trailer parts specialist with your trailer’s axle weight and spring dimensions. Keeping a printed parts list with your trailer will speed up future repairs. Regular inspection and greasing will extend the life of your Troxel suspension for years of trouble-free towing.