BDS 4-Inch Radius Arm Lift Kit for 2025–2026 Ram 2500 4WD Diesel-BDS NX2 Nitro Series

BDS 4-Inch Radius Arm Lift Kit for 2025–2026 Ram 2500 4WD Diesel | McClain Auto Part

Product Highlights

The 2025 and 2026 Ram 2500 diesel is a new generation platform. BDS engineered this 4-inch radius arm lift kit specifically for it. Four inches in the front and two and a half inches in the rear produces a leveled stance that eliminates the factory nose-down rake. The result is the aggressive proportions that define a properly built HD truck. Thirty-five inch tires fit the standard configuration. Thirty-seven inch tires open up with the right wheel combination.

What separates this kit from a generic lift solution is the diesel-specific engineering. The Cummins diesel places significantly more weight over the front axle than a gas engine in the same truck. That weight difference demands diesel-specific coil springs, heavier radius arms, and geometry correction components sized for the actual loads this platform produces. BDS builds this kit around those requirements. Furthermore, installation does not require a transfer case indexing ring or crossmember. That simplification reduces installation complexity without compromising structural integrity.

BDS backs this kit with their No Fine Print Warranty. Break it and BDS replaces it. No questions asked. At McClain Auto Part, we carry BDS because that warranty confidence reflects the engineering quality behind the product.

What Is Included

Front Suspension Components

Diesel-specific Pro-Ride coil springs are the engineering foundation of the front suspension upgrade. A coil spring designed for a gas Ram 2500 produces incorrect ride height and ride quality under the added weight of the Cummins diesel. BDS supplies a pair of full-length progressive rate Pro-Ride coil springs from high-tensile steel with wire diameter specifically engineered for the diesel application. Progressive rate construction delivers appropriate spring rates under light loads for ride comfort. Under heavier loads the rate increases for stability. Proper wire diameter sizing consequently eliminates the risk of premature coil bind that undersized springs produce at lift height.

Heavy-duty tubular radius arms replace the factory stamped steel units. Factory stamped steel radius arms are adequate at factory ride height. At four inches of lift on a heavy diesel truck they represent a strength and geometry limitation. The BDS tubular arms mount into the factory location for a clean installation. Caster adjustment is built into the design to allow precise geometry correction at the specific lift height achieved. An OE-style rubber bushing at the frame mount provides smooth and quiet operation. This is an important distinction from polyurethane bushings that produce road noise and harshness on a daily-driven work truck.

Forged drop pitman arm corrects steering angles at the new ride height. At four inches of lift the factory pitman arm geometry produces a drag link angle that causes bump steer and degrades steering feel under load. The BDS forged drop pitman arm restores the correct drag link angle at the new height. As a result, steering feel improves and bump steer is eliminated.

Rear Suspension Components

The rear of this kit lifts 2.5 inches to level the truck front to rear. BDS engineers the rear components to correct the geometry variables that rear lift introduces on the solid axle Ram 2500 platform. Axle positioning, bump travel limits, and suspension travel geometry all receive attention as part of the complete system.

Shock Options

Four shock options are available. Each delivers a different performance profile. Select based on how the truck is used day to day rather than defaulting to the highest specification without considering the application.

BDS NX2 Nitro Series

The NX2 is the right choice for Ram 2500 diesel owners who use their truck primarily for towing, hauling, and daily driving with occasional trail use. Nitrogen charging and twin-tube construction deliver consistent damping across the conditions a work truck encounters regularly. Ten-stage velocity-sensitive valving produces controlled damping over sharp road impacts and appropriate resistance through longer suspension events. The 1-3/8-inch high-flow piston moves fluid efficiently through the valve stack. Dual-welded mounting ends add structural strength. Self-lubricating seals consequently reduce maintenance requirements over a long service life. Silver powder coat finish resists undercarriage corrosion through year-round work truck use.

FOX 2.0 Performance Series IFP

The FOX 2.0 suits Ram 2500 owners who use their truck in more demanding off-road conditions alongside regular towing and hauling. The monotube internal floating piston design runs cooler under sustained off-road use than twin-tube alternatives. The two-inch impact-extruded aluminum body dissipates heat more effectively during extended off-road sessions. The 5/8-inch hard chrome-plated heat-treated alloy steel shaft resists bending under lateral loads during off-road articulation. CNC machined 6061-T6 aluminum mounting ends reduce weight while maintaining structural integrity. Application-specific valving is tuned for this specific Ram 2500 diesel application. As a result, the FOX 2.0 works with the spring rates and geometry of this kit rather than against them.

FOX 2.5 Performance Elite Series

The FOX 2.5 Performance Elite is the adjustable performance option for Ram 2500 owners who demand maximum off-road capability. It allows tuning of damping to match varying terrain, load, and speed conditions.

The 2.5-inch impact-extruded aluminum body delivers increased oil volume for better heat management during sustained high-speed off-road use. The external reservoir separates shock oil from high-pressure nitrogen. This separation prevents oil aeration during hard use and consequently maintains consistent damping performance across extended off-road sessions. The 7/8-inch hard chrome-plated heat-treated alloy steel shaft provides significantly more resistance to bending under the lateral loads that aggressive articulation produces on a heavy diesel truck. The DSC dual speed compression adjuster allows low-speed compression tuning without tools. The FOX 2.5 Performance Elite is fully serviceable for a lifetime of use. FOX backs it with a one-year manufacturer warranty.

FOX 2.5 Performance Series HTO

The FOX 2.5 HTO adds Hydraulic Top Out technology to the 2.5-inch performance platform. HTO delivers position-sensitive rebound damping control during the final stage of shock extension. This technology improves suspension composure during high-speed off-road use where the suspension extends rapidly. Controlled damping at the top of the stroke prevents the harsh feedback that uncontrolled extension produces. The result is a smoother and more controlled feel both on and off the pavement compared to standard rebound valving.

The 2.5-inch impact-extruded aluminum body and 5/8-inch hard chrome-plated shaft provide the structural foundation. The fully serviceable design supports a lifetime of use. FOX backs this shock with a one-year manufacturer warranty. For Ram 2500 owners who prioritize controlled suspension feel across a range of conditions rather than maximum adjustability, the HTO is consequently the right choice over the DSC-equipped Elite.

Recommended Tire and Wheel Combinations

This kit supports tire fitment up to 37 inches on the 2025 and 2026 Ram 2500 diesel 4WD. BDS recommends the following combinations based on application testing. Trimming may be required.

The 37-inch combination requires the specific 5.625-inch backspace to clear correctly with this kit. Deviating from these backspace specifications increases the risk of tire contact at the inner fender or steering components during full articulation on a loaded diesel truck.

Installation Note

This kit does not require a transfer case indexing ring or crossmember. Installation is therefore more straightforward than comparable lift kits that require these additional components. Experienced DIY installers with proper equipment handle this installation at home. A professional shop installation is recommended for owners who want professional alignment work completed alongside the lift to confirm proper caster and geometry settings after the radius arms go in.

BDS No Fine Print Warranty

BDS backs this kit with their No Fine Print Warranty. Break a component and BDS replaces it. No questions asked. This warranty reflects the engineering confidence behind the product. It also provides Ram 2500 owners with protection that most lift kit manufacturers do not offer at any price point.

Why McClain Auto Part Carries This Kit

We have supplied Ram truck owners from Cleveland since 2009. The products we carry reflect what we would put on our own trucks. BDS earns a place in our inventory on the Ram 2500 diesel platform because they engineer diesel-specific lift kits rather than adapting gas-application hardware to a heavier truck. The diesel-specific Pro-Ride springs, tubular radius arms, forged pitman arm, and No Fine Print Warranty in this kit reflect genuine engineering commitment to this application. For owners of 2025 and 2026 Ram 2500 diesel trucks who want a 4-inch lift that drives well, tows properly, and holds up to serious work truck use, this is the kit we recommend.

Before You Order

Confirm your model year as 2025 or 2026, drivetrain as 4WD, and engine as diesel before ordering. Select your shock option based on how the truck is used. NX2 for daily driving and moderate trail use. FOX 2.0 for more demanding off-road conditions. FOX 2.5 Performance Elite for maximum adjustable performance. FOX 2.5 HTO for controlled suspension feel with position-sensitive rebound technology.

Contact our Cleveland team with your year, drivetrain, engine, and shock preference. We confirm compatibility and current pricing before anything ships.

McClain Auto Part. Cleveland, Ohio. Ram truck parts and suspension components shipped nationwide. In business since 2009.