Load Assist Kits

38 products

Rear sag is the first sign your suspension is working too hard. Hitch up a camper, drop a pallet in the bed or fill a van with tools, and the back end squats, the headlights point up and the steering goes light. A BOSS load assist kit fixes that with a pair of air bags for trucks that sit alongside your factory springs and carry part of the extra weight.

Each kit is built for a specific vehicle. It comes with two BOSS Extreme Series air bags, upper and lower brackets, mounting hardware, SAE J844 air line and two Schrader fill valves on a stainless panel. You set the pressure for the load: run low pressure for everyday driving and add air when you tow or haul, until the truck sits level again. Most kits bolt on.

Kits are rated around 2,500–2,600 lb per side (see each product for its exact rating). If your truck has a rear lift, choose the triple bellow version where one is offered.

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Add on-board air with a BOSS compressor and an aluminum air tank.

Common questions

Will air bags help when I tow a trailer?
Yes. That's what they're built for. Adding air lifts the rear back to level under tongue weight, which brings your headlight aim and steering feel back to normal.

Do air bags replace my springs?
No. Load assist bags work alongside the factory springs. They share the extra weight, so the springs aren't carrying it all.

Do I need a compressor?
No. Each kit has Schrader valves, so you can fill the bags from any air source that fills a tire. A compressor lets you adjust pressure on the road.