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Hendrickson · Suspension & Steering
S-21800
In stock · ships from Knoxville
This is a Hendrickson rolling-lobe trailer air spring, often referred to as an '8709' bag.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 4 applications
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All confirmed applications for this part number.
Other applications
Other applications
Fits several Hendrickson trailer air-ride suspensions. Always confirm your suspension model before ordering.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 8 of 8.
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It replaces the factory air spring on many Hendrickson trailer suspension systems, providing variable-rate cushioning between the axle and frame. The rubber bellows and plastic piston work together to carry the vertical load and absorb road shock, helping protect the trailer and cargo. You replace it when the rubber is cracked, the bag leaks air, or the suspension won’t hold height, usually after years of service or if a failure causes uneven ride height.
Part Number: S-21800
AIR BAG (8709)
Unit: ea
Vendor: Aurora Parts & Accessories
Dealer: Post Onsite
Compatibility, alternatives, and more
Parts commonly needed alongside suspension & steering
