ContiTech AS9978 Air Spring Replaces S-28929 W01-358-9978

Shipping Information - Fast & Reliable

We ship Monday through Friday, excluding national holidays. Orders placed by 12:00 PM Central usually ship the same day, and later orders often still make it out the same afternoon. Parts coming from a secondary warehouse may ship the next business day. We'll get it to you as fast as we can.

30-Day Returns

Most products can be returned within 30 days of delivery. Items must be new, unused, and in the original packaging. A 20% restocking fee applies, and return shipping is paid by the customer. Original shipping charges and low order fees are not refunded. Special order parts cannot be returned.

Have questions? We're here to help and want the process to go smoothly.

Helpful Links:

Help Desk | Request a Return | Shipping, Returns and Exchanges Policies | Low Order Fee Policy

Continental Air Springs for Truck Applications

The weight of a truck, and therefore the axle load, fluctuates greatly depending on the payload. In order to provide the best possible solution to meet the resulting suspension requirements, virtually all commercial vehicle manufacturers make use of air springs. Air-suspended trucks with level control system provide constant chassis height and road clearance, regardless of the loading weight.

Constant and low natural frequency between tare and full load can only be achieved using air springs. This ensures effective cargo protection, even on poor road surfaces, excellent comfort and health protection for the truck driver and safe driving conditions. In addition, truck air springs enable the vehicle body to be raised and lowered for loading and unloading operations via manually operated chassis height control units.This enables easy truck height adjustment for trailer king pin connection, swap body handling or loading ramps

Continental truck air springs provide substantial performance benefits:

• High degree of comfort and can be installed in small spaces
• Fuel economy and payload increase thanks to their lightweight design
• Robustness across an extended operating temperature range

Continental Air Springs for Trailer / Semitrailer Applications

Air suspension on trailers provides protection for both payload and trailer body, including mounted equipment.

Trailer air springs further contribute to reduced road wear thanks to their low natural frequency, reduced unsprung axle mass and reduced wheel load fluctuations. This aspect is of growing importance as traffic volume is increasing.

As a rule, each axle has two air springs. In multi-axle combinations, one axle is frequently provided with an axle-lifting device to reduce tire wear on empty runs or when the vehicle is only partially loaded. Convoluted air springs are normally used for raising and lowering lift axles.

Continental trailer air springs are designed with a specific focus on the following aspects:

• Optimum cost-effectiveness achieved through the selection of specific materials and components in line with the application requirements
• Robust solutions incorporating a high degree of functionality