Air Spring W01-358-9781 – 1T15ZR-6 / 1R12-603

The W01-358-9781 air spring is a rolling-lobe suspension air bag used on many Freightliner and trailer suspensions. Built with a heavy-duty 1T15ZR-6 style bellows, 9" top plate and 10.6" piston, it delivers stable ride height, excellent load support and long service life in harsh Canadian conditions. Ideal for on-highway tractors and air-ride trailers seeking OEM-level performance at an aftermarket price.

Specifications:
o Firestone number: W01-358-9781
o Bellows: 1T15ZR-6 (or 1T15 X-Series replacement)
o Type: Rolling lobe air spring
o Extended height: 23.0 in (approx. 584 mm)
o Compressed height: 8.75 in (222 mm)
o Top plate diameter: 9.0 in (229 mm)
o Piston width: ≈10.6 in (270 mm)
o Typical weight: ~13.2 lb (6.0 kg)