4.5" Lift Stage 4 Suspension System Kit w/ Radius Arms

Features:

• 4.5" front lift for diesel Super Duty trucks
• Dual-rate coils balance comfort and control
• Radius arms increase strength and steering clearance
• No drop brackets needed for arm installation
• Remote reservoir shocks resist heat and fade
• Up to 50% more front wheel travel
• Adjustable track bar improves axle alignment
• Dual stabilizers reduce tire shake and feedback
• 5" heavy-duty rear blocks handle towing loads
• Stainless braided brake lines resist wear and heat
• Shocks are fully rebuildable and re-tunable
• Covered by ICON lifetime component warranty

Build Your Truck To Handle More Than Pavement

If your Super Duty looks tough but still feels limited off the lot, the ICON K65903R 4.5" Stage 4 Suspension System is your next move. This kit isn’t just about adding lift, it’s about unlocking a whole new level of control, comfort, and confidence whether you’re pulling trailers, hitting remote job sites, or pushing into backcountry terrain. The ride quality is noticeably smoother on the road thanks to ICON’s dual-rate front coils, and when the terrain gets rough, the secondary spring rate kicks in to keep you from bottoming out. Paired with ICON’s 2.5 remote reservoir shocks, the system controls heat buildup on long hauls or off-road climbs, giving you consistent damping across varied conditions. The fabricated radius arms don’t just look stout, they deliver real strength, better ground clearance, and improved caster geometry without needing drop brackets. With increased wheel travel and tighter steering control from dual stabilizers, you’ll feel a more planted, capable truck beneath you. It’s the kind of upgrade that makes your truck feel less like a factory build and more like a purpose-built machine.

Suspension Geometry And Control Built For Real Loads

This Stage 4 system is engineered to meet the demands of serious towing, off-roading, and heavy-duty use across the 2023-2025 Super Duty diesel platform. Up front, ICON’s dual-rate coil springs are tuned for diesel weight, with a soft initial response for comfort and a firmer second stage to maintain control when loaded or compressed. The fabricated radius arms include built-in caster cams, which help retain proper alignment and steering response after the lift, while eliminating the need for bulky drop brackets. The adjustable track bar works alongside the drop bracket to center the axle, reduce bump steer, and eliminate the flex and play that comes with factory bushings. ICON’s 2.5 Aluminum Series shocks feature remote reservoirs that increase oil capacity and cooling surface area, reducing the risk of fade over long durations or under repeated stress. Rear lift comes from heavy-duty 5-inch fabricated blocks and extended U-bolts, built to handle serious towing and hauling without flex or fatigue. Stainless steel braided brake lines, sway bar drop brackets, and bump stop spacers round out the system, delivering a complete, high-performance suspension solution with long-term durability in mind.

Fits: 2023, 2024, 2025 Ford F250/F350 Super Duty DIESEL

Notes:

• Only for 4WD diesel F‑250 / F‑350 trucks
• Includes fabricated radius arms with caster adjustment
• No drop brackets needed in front section
• Remote reservoirs aid shock cooling under heavy use
• Track bar drop bracket corrects bump steer geometry
• Adjustable track bar allows axle centering and tuning
• Rear lift via heavy-duty 5" blocks and U‑bolts
• Stainless braided front brake lines included
• Components are CNC, laser cut, and brake formed
• Shocks and stabilizers are rebuildable and tunable
• Lifetime warranty on springs and fabricated parts