For Kenworth Air Spring Bag – Replaces W01-358-8864 / WA01-8864C

Upgrade your truck’s suspension performance with the ROADWEST Air Spring Bag for Peterbilt & Kenworth, engineered as a heavy-duty replacement for selected OEM and aftermarket air ride systems. This suspension air spring is designed to replace popular reference numbers W01-358-8864 and WA01-8864C used on selected Peterbilt and Kenworth trucks.

Built from imported high-density rubber with multi-ply bellows and a reinforced piston, this air spring exceeds typical OEM requirements. The robust construction delivers greater durability, better load support and longer service life compared with many standard air suspension bags, helping your truck maintain the proper ride height and stability under load.

By effectively absorbing shocks and vibration, the ROADWEST air spring bag reduces harsh impacts transmitted to the frame and cab. This improves ride comfort, driver fatigue and braking stability, making it a smart choice when the original air bag is leaking, cracked or worn.

• Designed for Peterbilt & Kenworth trucks – fits suspensions using cross reference numbers W01-358-8864 and WA01-8864C (match to existing part number before purchase).
• Premium quality air ride – high-density rubber bellows and a strong piston/base design provide excellent load capacity and long service life.
• Safety & comfort – air spring bags help reduce physical collision impact on passengers, absorb vibration and support more controlled braking.
• Better driving experience – smoother ride, reduced bounce and more stable handling when loaded or empty.
• Easy installation – designed as a direct replacement when correctly matched by part number; no major modifications required in typical applications.
• Warranty-backed – includes a 1-year warranty and 100% quality assurance for added peace of mind.

Key air spring components:

• Piston – lower section of the air spring, made from aluminium, steel or composite plastic. Provides the lower mounting arrangement using threaded holes or studs.
• Girdle hoop (centre ring) – ring located between the convolutions of a convoluted-type air spring that helps maintain shape and stability.
• Bellows – the core of the air spring, consisting of multiple plies: an inner layer, two plies of cord-reinforced fabric and an outer protective layer for strength and flexibility.
• Bumper (bump stop) – solid moulded rubber fail-safe device used on many suspension applications to help protect the vehicle and suspension in the event of sudden air pressure loss.

Fitment reminder:

• This is not a universal air spring.
• Always confirm the part number on your original air bag or suspension specification before ordering.
• Only purchase if your existing air spring matches one of these numbers: W01-358-8864 or WA01-8864C.
• If you are unsure, consult your mechanic or parts manager to verify compatibility.