AIR TRAC SPRING 75-125

Description Part Number: 75-125 2 Leaf Spring; OEM No. 03-02432 ; Width = 4 ; (A)= 24-3/4 ; (B)=4-3/8; (D)= 2-9/16; 23K lb Capacity Product Overview The Air Trac spring (75-125) is part of the rear suspension system, working alongside air bags and suspension hardware to support load and control axle movement. It’s built to handle constant stress from weight, road conditions, and torque. Over time, these springs wear out, lose strength, or develop cracks. This replacement brings the suspension back to a stable, working condition. What the Part Does This spring helps control the axle position and supports the overall suspension system. While air bags handle ride height and cushioning, the spring provides structure and stability, especially under load. It keeps the axle properly located, reduces unwanted movement, and helps the suspension react predictably when the truck is loaded, braking, or going over uneven roads. Common Problems This Part Solves When an Air Trac spring starts wearing out, the truck doesn’t handle the same. You might notice the rear end feeling loose, unstable under load, or shifting more than it should. Other signs include uneven ride height, abnormal tire wear, or clunking noises coming from the suspension. In some cases, cracked or weakened springs can throw off alignment and put extra stress on nearby components like torque rods and bushings. Why Replacement Matters When the axle isn’t held firmly in place, it changes how the truck handles under load and during braking. Replacing the spring keeps the suspension geometry where it should be and helps prevent additional wear on air bags, mounts, and linkage components. It’s one of those parts where waiting too long usually leads to more parts needing replacement. Compatibility and Fitment This Air Trac spring replaces part number 75-125 and is designed for specific suspension setups. Always match the part number and confirm your suspension configuration before ordering. These are not one-size-fits-all components. Installation and Service Notes You have to support the axle, remove the old spring, and install the new one with proper torque on all mounting hardware. This is not a quick roadside job. You need proper equipment and safety steps are important here. While replacing the spring, inspect air bags, torque rods, bushings, mounts, etc. Suspension parts wear together and catching issues early saves time later. Use Case This part is used in suspension rebuilds, ride quality complaints, or when dealing with alignment and handling issues. Common for fleet trucks running heavy loads or high mileage where suspension wear is expected. About Us We’re a family-owned group of Peterbilt dealerships dedicated to getting you the parts you need quickly and affordably. Whether you’re looking for Paccar OEM parts, reliable aftermarket replacements, or popular upgrades like seats and filters, we make it easy to keep your truck running and on the road. If you don’t see what you need online, just give us a call or send an email — chances are we can get it. We pride ourselves on fast service, fair prices, and being a partner you can depend on when downtime isn’t an option   FAQs Q1: How do I know if the Air Trac spring is worn out? A: Look for handling changes first: loose rear end, uneven ride height or unusual tire wear. You may also hear clunking or see visible wear or cracking on the spring itself. Q2: Should springs be replaced in pairs? A: In many cases, yes. If one side is worn, the other side has likely seen similar use. Replacing both helps keep the suspension balanced. Q3: Is this something I can install myself? A: It depends on your setup and tools. Suspension work requires proper support equipment and safety precautions. Most people handle this in a shop environment. Q4: Will this fix ride height issues? A: If the issue is related to spring fatigue or structural support, yes. If it’s air system-related, like leaking air bags or valves, those will need attention too.