Air Spring Bag for Hendrickson Trailers - Durable Replacement Part

In this review of the Air Spring Bag for Hendrickson Axle Trailers, the bottom line is straightforward: this replacement is built for fleets and technicians who need a robust, direct-fit air spring that matches common Hendrickson part numbers. The reviewer found the kit's strongest selling point is its combination of heavy-duty construction and precise dimensions, which make installation predictable when the correct part number is confirmed. This review highlights compatibility, material quality, and practical fit details so a buyer can decide quickly whether this is the right suspension part for their trailer.

Key Features

• Compatibility: Fits common Hendrickson and aftermarket part numbers including W01-358-9978, C-28929, S-28929 and several AS/HD variants, reducing the risk of ordering the wrong item when matched to your trailer.
• Material quality: Constructed from 4.5-5.00mm high density rubber that exceeds OEM thickness expectations, offering strong resistance to wear and environmental exposure for longer service life.
• Reinforced hardware: Uses 4140 grade steel studs that are 25% stronger than comparable studs, which improves mounting durability under heavy loads and repeated cycles.
• Tested for leakage: Each spring bag is tested for maximum leakage, providing confidence in airtight performance and reducing the likelihood of premature failure.
• Clear dimensions: Published top plate width, piston width and compressed/extended heights help ensure proper fitment during replacement and simplify cross-checking with the trailer specification.

Who It's For

This air spring bag is aimed at fleet maintenance teams, independent trailer repair shops and owners of Hendrickson axle-equipped trailers who need a reliable, direct replacement for the listed part numbers. The product suits those who prefer to verify fit by dimensions and part reference before ordering to avoid downtime.

It is less appropriate for buyers who cannot confirm the exact part number or those needing custom or vehicle-specific engineered suspension solutions beyond the stated compatibility. If a precise OEM cross-reference cannot be matched, shoppers should seek guidance before purchase.

Pros & Cons

Pros

• Heavy-duty rubber construction gives improved durability over thinner alternatives.
• Reinforced 4140 grade steel studs reduce the risk of stud failure under load.
• Fully tested for leakage, which helps ensure reliable air retention in service.

Cons

• Requires careful part number and dimension verification before purchase to ensure a perfect fit.

Specifications

Brand	STILEALUS
Top Plate Width	9.00 in
Piston Width	10.16 in
Compressed Height	7.90 in
Extended Height	18.00 in
Weight	15.10 lbs
Warranty	3 Year Unlimited-mileage Quality Guarantee

Our Verdict

The Air Spring Bag for Hendrickson trailers is a practical, value-oriented replacement for users who can confirm the fit by part number or dimensions. With thicker rubber, reinforced studs and leakage testing, it offers tangible durability benefits for heavy-duty use. Purchase it when the compatibility matches, and it will serve as a dependable replacement without the premium cost of OEM-branded parts.

Frequently Asked Questions

Will this fit my Hendrickson axle?
Check the exact part number and compare the listed dimensions; it fits W01-358-9978, C-28929, S-28929 and several AS/HD variants when the specs match.

How durable is the construction?
The bag uses 4.5-5.00mm high density rubber and 4140 grade steel studs reinforced by 25% for improved durability over standard replacements.

What warranty is included?
The product includes a 3 year unlimited-mileage quality guarantee; contact the seller for warranty service or questions.