Specifications
- Brand
- FOX
- Part #
- 981-02-393
- UPC
- 714686857499

Fox 4.0 Factory Series 18in P/B Res. 5-Tube Bypass Shock (3 Comp/2 Reb) 1-1/8in. Shaft (32/70) - Blk
$2279.95
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FOX 4.0 External Bypass Shock. Race-winning technology for extreme off-road performance.
Key Features
- Fits custom off-road applications requiring advanced suspension control.
- Features a 4.0-inch diameter body and 18-inch stroke for significant travel.
- External bypass design with 3 compression and 2 rebound adjustment tubes for fine-tuned damping.
- Durable zinc-plated seamless alloy body resists corrosion and withstands harsh conditions.
- Features a strong 1-1/8 inch 17-4 H900 stainless steel shaft for reliability.
- Uses FOX Racing Oil, formulated for ultimate performance and consistent damping.
⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more
Product Details
When you're pushing your vehicle to its limits on rough terrain, whether it's flying over desert whoops or navigating challenging rock climbs, having suspension that can keep up is critical. This FOX 4.0 Factory Series bypass shock is built to handle that kind of punishment, offering advanced damping control to match your driving style and the terrain you're tackling.
This shock features a 4.0-inch diameter body and an 18-inch stroke, giving it the capacity to absorb large impacts. The external bypass design allows for precise tuning of compression and rebound damping with its 3 compression and 2 rebound adjustment tubes, meaning you can fine-tune how the suspension reacts to bumps and G-forces. It's built with a durable zinc-plated seamless alloy body and a 1-1/8 inch 17-4 H900 stainless steel shaft, known for its strength and corrosion resistance. The black anodized CNC-machined aluminum components not only look sharp but are also built to last. Inside, it uses FOX Racing Oil, developed for ultimate performance, ensuring consistent damping even under heavy use. This shock is also rebuildable and serviceable, so you can maintain its performance over time.
This is a serious piece of suspension hardware for those who demand the best. It's designed to be a direct replacement for many custom off-road applications where enhanced damping and adjustability are key. Consider how you plan to tune your suspension; the external bypass adjusters allow for significant changes to how the vehicle handles, so take your time to dial it in for your specific needs.
Specifications
- Brand
- FOX
- Manufacturer Part #
- 981-02-393
- UPC
- 714686857499
Frequently Asked Questions
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Fox 4.0 Factory Series 18in P/B Res. 5-Tube Bypass Shock (3 Comp/2 Reb) 1-1/8in. Shaft (32/70) - Blk
