Peterbilt 386 Air Springs & Level Valves

Frequently Asked Questions About Peterbilt 386 Air Springs & Level Valves

What do air springs and level valves actually do on my Peterbilt 386?

Air springs (air bags) support the weight of the cab or suspension and absorb road shock by inflating and deflating with compressed air. Level valves (also called height control valves) automatically regulate how much air enters or exits the air springs to keep the cab or axle riding at the correct height as load conditions change. Together, these components help maintain a smooth, stable ride and consistent ride height under varying loads.

How do I know if I need to replace my air spring, level valve, or both?

Common signs of a failing air spring include visible cracks, bulges, leaks, or a sagging cab or suspension that does not return to normal ride height. A bad level valve often causes the cab or axle to sit too high, too low, or to bounce excessively, even if the air spring itself is in good condition. If you are unsure which part is causing the issue, a shop can perform an air leak and linkage test to pinpoint whether the spring, the valve, or the linkage between them needs attention.

Will these air springs and level valves fit my specific Peterbilt 386?

Fitment can vary based on your truck's build date, cab suspension type, and axle configuration, since Peterbilt used different air spring and valve setups across production years. Always check the part number and specifications listed on the product page against your truck's OEM part number or VIN before ordering to confirm a correct match.

Are these air springs and level valves OEM parts or aftermarket replacements?

Our Peterbilt 386 air springs and level valves include both OEM and quality aftermarket options, and each product listing specifies which type you are purchasing. Aftermarket parts are built to match OEM fit, form, and function, giving you a reliable alternative that is often more budget-friendly than going through the dealer.

Can I install a new air spring or level valve myself, or should I have a professional do it?

Many experienced technicians and owner-operators with the right tools can replace an air spring or level valve themselves, especially if they have done similar suspension or air system work before. That said, these components are tied directly to ride height, cab stability, and air system pressure, so if you are not comfortable working with air lines and linkage adjustments, it is worth having a qualified truck repair shop handle the installation to ensure everything is set up and adjusted correctly.