20505399 Air Spring | 1R12-405 / 1R12-595 | Newstar S-22540 | S&S Truck Replacement

20505399 Air Spring | 1R12-405 / 1R12-595 | Newstar S-22540 | S&S Truck Replacement

Product Summary

20505399 is a heavy-duty air spring assembly commonly used in Volvo and Mack truck rear suspension systems. This unit is a high-quality aftermarket replacement manufactured by S&S Truck under Newstar part number S-22540. It cross-references Firestone air spring models 1R12-405 and 1R12-595 and is engineered to maintain proper ride height, load support, and suspension performance in demanding on-road applications.

Specs & Features

• Part Number: 20505399
• Alternate Part Numbers: 1R12-405, 1R12-595, W01-358-8829, FS8829, S-22540
• Top Plate Mount: (2) Studs
• Bottom Plate Mount: (1) Stud
• Extended Height: Approx. 22"
• Condition: New Aftermarket Replacement
• Manufacturer: S&S Truck / Newstar
• Application: Volvo and Mack rear air suspension systems

What’s Included

• (1) Air Spring – S-22540 / 20505399

Fitment Notes

This air spring cross-references multiple OEM and aftermarket part numbers. Confirm fitment by mount configuration, dimensions, and suspension application prior to installation.

Commonly used on select Volvo VN and VNL models, as well as Mack truck platforms utilizing this air spring size.

Image Disclaimer

Images may show the actual item or a representative equivalent. Packaging may vary depending on stock.

Warranty Policy

This aftermarket replacement part is sold as-is with no warranty expressed or implied. Please verify compatibility before purchase.

Location

Ships from our warehouse in Ohio.

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