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Torque · Suspension & Steering
TR9978
In stock · ships from Knoxville
This is a heavy-duty trailer air spring, also known as an air bag, used in the suspension system of semi-trailers.
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Other applications
Other applications
Cross-references indicate use on Hendrickson trailer suspensions (S28929, C28929, etc.) and other common trailer air-ride systems. This is a heavy-duty trailer application; verify correct bracket and height match before ordering.
Part data verified against 4 catalog sources
Numbers this part supersedes or interchanges with. Showing 11 of 11.
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It replaces the traditional steel spring, using compressed air to support the load and cushion the vehicle from road shock. When inflated, it maintains a consistent ride height regardless of how heavy the trailer is loaded, which improves stability and protects cargo. You would typically replace this when your existing air spring is leaking, cracked, or no longer holding air, causing the trailer to sag or ride roughly.
Part Number: TR9978
AIR SPRING
Unit: ea
Vendor: Torque
Dealer: KP Services Crossville
Compatibility, alternatives, and more
Parts commonly needed alongside suspension & steering
