The Bilstein 24-185981 is a rear shock from the B6 4600 series, a monotube damper with a 46mm body meant to replace the factory unit on 4WD Ford Super Duty trucks. It comes in the brand's yellow coating with a blue straight boot. A monotube layout keeps the damping fluid and gas in one cylinder, which helps resist fade on long grades, repeated bumps, and hard use, where a stock or cheap twin-tube damper tends to fall off.
Buy this shock when you want better body control and a more planted rear end without giving up the factory ride. It is aimed at owners searching for a Bilstein B6 4600 rear shock for a 4x4 F-250, a 24-185981 monotube replacement, or a towing-capable rear damper upgrade. Because the part is sold individually, plan to replace the rear pair together so both sides damp the same way. Confirm your exact model year and trim, including the 2004 F-250 XL 4WD, against the manufacturer's fitment guide before ordering, since listings for this part number do not agree on the starting year. Installation is a bolt-on rear job, so a standard shop lift and basic hand tools cover it, but check the manufacturer's torque specs before final assembly.
