An F-350 doesn't get babied. Monday through Friday it's a gooseneck, a bed full of material, and a job site road nobody grades. Saturday it's the toy hauler to the desert or the camper up a forest road. The factory shocks were picked to ride well on an empty truck at a dealer test drive, and that isn't how yours spends its life. With weight on the hitch, the heavy front axle starts to porpoise over expansion joints and the rear keeps moving after the bump is gone. On a washboard road the shocks heat up and fade right when you need them most.

The 8100 ZoneControl R is built for that work. Each corner gets a 2.65" monotube with a 60mm piston and a remote reservoir, so there's more oil to soak up heat and more piston area to control a heavy axle. ZoneControl R adds a second rebound piston near full extension that catches the axle before it tops out, so one bump stays one bump. The truck settles faster, tracks straighter with a trailer behind it, and stays composed on dirt when it's loaded down.

What the Letters Mean

• 8100 ZoneControl R. 2.65" monotube with a remote reservoir and a second rebound stage near full extension. Fixed valving.
• 8100 ZoneControl R DSA. The same shock with high-speed and low-speed compression knobs. Firm it up for the fifth wheel or a full bed, and back it off for the empty run home or a fast dirt road.

Choose Your Set

• Run fixed front and rear if: the truck does the same job every week, with the same trailer and the same load, and you want to install it and forget it.
• Run DSA front and rear if: the load changes. A loaded gooseneck on Tuesday, an empty bed on Wednesday, a camper on the weekend. Or you run 35s or 37s fast on dirt.
• Run DSA front, fixed rear if: you feel it in the front end (big tires, a plow mount, or a heavy bumper and winch) while the rear already rides fine on the factory overloads.

The Real Trade-Offs

• It needs front lift. These aren't for a stock-height truck. Plan on 2-2.5" springs or spacers on a diesel (1-2.5" on gas).
• Factory wheels won't work up front. Bilstein lists the fronts as not compatible with OE wheel backspacing. Max 4.75" backspacing (8.5" wheel at zero offset); largest tire 37x12.5".
• Reservoir mounting may need drilling. If the frame has no factory hole, Bilstein's kit uses threaded inserts in new holes. The wheel well shroud may need trimming.
• Rear lift is 0-1". Made for a stock or mildly leveled rear. If you've lifted the rear more than that, call us before you order.
• Shocks don't add capacity. They control the springs you have. If the truck sags under the hitch weight you carry, that's a spring or airbag job, and these shocks will work with that setup.

Install Notes

• Fits 2017-2026 Ford F-350 Super Duty 4WD with 1-2.5" (gas) or 2-2.5" (diesel) of front lift. Rear fitment for single rear wheel vs. dually: call us to confirm.
• Trucks with the electric steering assist module use a bent reservoir plate on the driver side (included).
• Upper front stem nut: 34 ft-lb; hold the pin with a 6mm Allen. No impact guns.
• Factory DSA settings: high-speed 6 clicks from full firm, low-speed 13.
• Alignment and headlight aim after install.

Who Should Buy These

F-350 owners on a 2-2.5" level with 35s or 37s whose truck earns its keep during the week and tows the toys on the weekend, and who want it to ride like it's built for the load.

Questions about your build, your trailer, or your lift? Call us at (213) 433-3616.