Peterbilt 352 Torque Rods & U-Bolts

Frequently Asked Questions About Peterbilt 352 Torque Rods & U-Bolts

What are the correct torque rod lengths for my Peterbilt 352, and how do I measure them?

Torque rod lengths for Peterbilt 352 models typically range from 21 to 30 inches, measured center-to-center between the bushing holes. To measure correctly, remove the existing rod and measure from the center of one bushing hole to the center of the other. Common lengths include 24-inch for front suspension and 28-inch for rear applications. Always verify your specific model year and suspension configuration, as cab-over models may require different lengths than conventional models.

What's the difference between standard and heavy-duty torque rods, and which do I need?

Standard torque rods are suitable for most highway and regional hauling applications, typically rated for 40,000-50,000 lb suspensions. Heavy-duty torque rods feature thicker tubing walls, reinforced ends, and upgraded bushings designed for 52,000-70,000 lb suspensions or severe-duty applications like logging, construction, or heavy hauling. If your Peterbilt 352 regularly carries maximum loads or operates off-road, heavy-duty rods provide better durability and reduced maintenance intervals.

What size U-bolts fit Peterbilt 352 axles, and are they side-specific?

Peterbilt 352 U-bolts vary based on axle manufacturer and capacity. Common sizes include 3-inch round for standard axles and 3.5-inch for heavy-duty applications. Square U-bolts typically measure 2.75 to 3.25 inches. Thread diameters range from 5/8-inch to 7/8-inch. U-bolts are not side-specific but must match your spring pack width, which typically ranges from 3 to 4 inches. Always confirm your axle model and spring specifications before ordering.

How difficult is the installation, and what special tools are required?

Torque rod replacement requires basic hand tools plus a torque wrench capable of 300-450 ft-lbs for proper bushing installation. Plan 2-3 hours per axle for an experienced mechanic. The most challenging aspect is removing seized bushings, which may require a hydraulic press or bushing removal tool. U-bolt installation is straightforward but requires proper torque sequencing: tighten in a cross pattern to 200-300 ft-lbs depending on size. Always replace U-bolts in complete sets to ensure even clamping force.

Are aftermarket torque rods and U-bolts as reliable as OEM parts?

Quality aftermarket torque rods and U-bolts from reputable manufacturers often match or exceed OEM specifications while costing 30-50% less. Look for parts that meet SAE J133 standards for torque rods and Grade 8 specifications for U-bolts. Premium aftermarket options feature improved bushing compounds, enhanced corrosion resistance, and greaseable designs not always found in OEM parts. Avoid economy-grade imports that may use inferior steel or improper heat treatment, as these can fail prematurely under heavy loads.