Peterbilt 359 Leaf Springs, Hangers & Acc.

Frequently Asked Questions About Peterbilt 359 Leaf Springs, Hangers & Acc.

What years do these leaf springs fit, and are they compatible with both long hood and short hood 359 models?

Our Peterbilt 359 leaf springs are designed to fit models from 1967 through 1987. They are compatible with both long hood (127" BBC) and short hood (119" BBC) configurations. However, spring pack thickness and arch measurements can vary depending on your truck's original suspension setup and any modifications. We recommend checking your current spring measurements or contacting us with your OEM for exact fitment verification.

What's the difference between 2-inch and 3-inch wide leaf springs, and which one do I need?

The width refers to the individual leaf blade width in your spring pack. Most Peterbilt 359s came with 3-inch wide springs from the factory, which provide better load distribution and durability for heavy-duty applications. The 2-inch springs are typically found on lighter spec trucks or older models. To determine which you need, measure the width of your current spring leaves or check the stamping on your existing spring pack. Using the wrong width can cause alignment issues and premature bushing wear.

Do I need to replace the hangers and bushings when installing new leaf springs?

While not always mandatory, we strongly recommend replacing hangers, shackles, and bushings when installing new leaf springs. Worn hangers can cause improper spring alignment, leading to irregular tire wear and handling issues. Old rubber bushings often compress or deteriorate, negating the benefits of new springs. A complete refresh typically includes front hangers, rear shackles, pivot bolts, and polyurethane or rubber bushings. This ensures proper suspension geometry and maximizes the lifespan of your new springs.

What tools and equipment do I need for installation, and how long does it typically take?

Essential tools include a heavy-duty floor jack (minimum 20-ton capacity), jack stands rated for commercial trucks, impact wrench, torque wrench capable of 450-500 ft-lbs, spring compressor or C-clamps, and basic hand tools. You'll also need penetrating oil for rusty bolts and anti-seize for reassembly. Professional installation typically takes 4-6 hours per axle, while DIY installations often require 6-10 hours depending on rust and accessibility. Always support the frame properly and never work under a truck supported only by jacks.

How do I know if I need standard or heavy-duty leaf springs for my application?

Standard leaf springs are suitable for highway tractors and general freight hauling, typically featuring 10-12 leaves in the pack. Heavy-duty springs have 13-16 leaves and are designed for vocational applications like dump trucks, heavy haul, or off-road use. Check your door jamb sticker for the original spring capacity rating, or count the leaves in your current spring pack. Consider your typical load weight and operating conditions - if you frequently haul at or near maximum capacity, heavy-duty springs will provide better stability and longevity without sacrificing too much ride quality when empty.