BDS 6-Inch Radius Arm Lift Kit | FOX 2.5 Performance Elite | Ram 3500 4WD Diesel 2019–2026 | With Overload Leaf | 6-Bolt | SKU: 1683FPE

The BDS 1683FPE is a 6-inch radius arm front lift kit with FOX 2.5 Performance Elite external reservoir shocks for the 2019–2026 Ram 3500 4WD diesel with factory rear overload leaf springs and a 6-bolt front axle. Heavy-duty BDS radius arms replace the factory arms, correcting caster at lift height and reducing bushing bind. Diesel-tuned front coil springs deliver 6 inches of lift at the correct spring rate for the Ram 3500 diesel's front-end weight. FOX 2.5 PE external reservoir shocks deliver advanced valving and heat-managed damping for sustained towing and off-road performance at lifted height.

This kit has five hard fitment confirmations before it applies to your truck.

First — rear suspension: this kit is calibrated for Ram 3500 trucks with factory rear overload leaf springs. If your Ram 3500 does NOT have factory rear overload leaf springs, order 1682FPE — the overload and non-overload kits are not interchangeable.

Second — axle: 6-bolt front axle required. Confirm your front axle bolt pattern before ordering.

Third — engine: diesel-tuned coil springs. Ram 3500 gas requires a different kit — gas and diesel springs are not interchangeable.

Fourth — generation: 2019–2026 only. The 2018 and earlier Ram 3500 is a different platform and is not compatible.

Fifth — drivetrain: 4WD only. Ram 3500 2WD is not compatible.

Text (469) 407-7538 to confirm all five before the order ships.

Component Specifications

What Is and Is NOT Included

Critical Compatibility

Five fitment confirmations required before ordering.

Not sure about overload leaf configuration or axle bolt count? Text (469) 407-7538 before ordering.

With Overload Leaf vs. No Overload Leaf — Which Kit Do You Need?

How to confirm your rear spring configuration: Visually inspect the rear axle leaf spring pack. An overload pack has an additional leaf that sits above the main pack and contacts the axle only under heavy load — visible as an extra leaf that does not contact the axle at rest. Common on higher trim levels and work truck configurations. Text (469) 407-7538 with your VIN to confirm before ordering.

How to confirm your front axle bolt count: Count the lug bolts on your front axle flange. This kit requires a 6-bolt configuration. Text (469) 407-7538 with your VIN if you need confirmation before ordering.

Radius Arm Upgrade at 6-Inch Lift — Why It Matters

At 6 inches of lift on the Ram 3500 diesel platform, factory radius arms reach the outer limits of their designed geometry — caster deviation accelerates, bushing bind under articulation increases, and axle centering degrades without correction. The BDS heavy-duty radius arms are engineered specifically for 6-inch lift height on the diesel platform, correcting caster, reducing bind, and supporting the axle loads a Ram 3500 diesel work truck actually carries.

Installation Notes

Professional installation is required. A 6-inch radius arm lift on a diesel platform requires a qualified suspension shop with experience on heavy-duty truck platforms. Do not attempt DIY installation.

Full front-end alignment is mandatory after installation. Do not drive on public roads before alignment is completed. At 6-inch lift on the diesel platform, correct alignment is critical for tire wear and steering geometry under towing load.

Driveline inspection is mandatory at 6-inch lift. At 6 inches, driveshaft angles change significantly from factory. Inspect U-joint operating angles after installation and confirm they are within acceptable range before towing. Driveshaft modification may be required depending on your specific configuration — confirm with your installer before the job begins.

External reservoir routing. Follow BDS and FOX installation instructions for reservoir placement. Avoid pinch points, heat sources, and moving components during routing. Improper reservoir placement can damage the reservoir line and void the FOX warranty.

Overload leaf and axle confirmation is mandatory before ordering. This kit is non-returnable once installed. Confirm both your rear spring configuration and front axle bolt pattern before the order ships. Text (469) 407-7538 if you need help confirming either.

Torque all fasteners to BDS specification. Torque specs are included in the BDS installation instructions. Do not estimate torque values on a diesel-weight platform.

FOX shock break-in period. Allow FOX 2.5 PE shocks to complete the manufacturer-recommended break-in period before aggressive off-road or heavy towing use.

Text (469) 407-7538 to confirm rear spring configuration, axle bolt count, engine, and drivetrain before ordering.

The Obsidian Take

The BDS 1683FPE is the correct kit for the 2019–2026 Ram 3500 4WD diesel owner with factory rear overload leaf springs and a 6-bolt front axle who wants 6 inches of front lift with premium FOX 2.5 PE damping. The radius arm upgrade corrects the geometry that 6 inches of lift demands on the diesel platform — caster correction, bushing bind reduction, and axle centering — while the FOX 2.5 PE external reservoir handles the sustained damping demands of a diesel work truck under towing load. The reservoir is what separates the 2.5 PE from a standard shock body in this application: consistent performance on repeat towing runs and rough terrain, where a standard shock begins to fade.

If your Ram 3500 does not have factory rear overload leaf springs, order 1682FPE — the overload and non-overload kits are calibrated differently for the rear suspension configuration and are not interchangeable. Ordering the wrong variant affects geometry and ride quality under the exact loads this truck is built to carry.

If your Ram 3500 is gas, diesel-tuned springs are not correct for the lighter gas engine weight — a different kit is required. If it is a 2018 or earlier, the platform is different and this kit does not apply.

Five prerequisites confirmed — overload leaf, 6-bolt axle, diesel, 4WD, 2019–2026 — the 1683FPE is the complete, correctly-specified 6-inch solution for the Ram 3500 diesel work truck that tows hard and needs every component of its front-end geometry correct when it does.

Common Questions

How do I confirm my Ram 3500 has factory rear overload leaf springs?
Visually inspect the rear axle leaf spring pack. An overload pack includes an additional leaf that sits above the main pack and contacts the axle only under heavy load. Common on higher trim levels and work truck configurations. Text (469) 407-7538 with your VIN and we will confirm before your order ships.

How do I confirm my Ram 3500 has a 6-bolt front axle?
Count the lug bolts on your front axle flange — 6-bolt configuration required. Text (469) 407-7538 with your VIN if you need confirmation before ordering.

What is the difference between 1683FPE and 1682FPE?
Both kits fit the 2019–2026 Ram 3500 4WD diesel with a 6-bolt front axle and deliver 6 inches of front lift with the same BDS radius arms, diesel-tuned springs, FOX 2.5 PE shocks, and track bar correction bracket. The difference is rear spring calibration — 1683FPE is for trucks with factory rear overload leaf springs and 1682FPE is for trucks without. They are not interchangeable.

What is the driveline inspection for and can I skip it?
At 6 inches of lift, driveshaft angles change significantly from factory. U-joints operating outside their designed angle range wear rapidly and can fail under heavy diesel towing load. The inspection confirms whether your driveshaft requires modification. On a diesel towing platform at 6-inch lift, this is not optional.

Does this kit lift the rear of the truck?
This kit addresses front lift via the radius arm upgrade. Rear lift components are not included. Confirm rear lift requirements with your installer before ordering if needed.

Is this a DIY install?
No. A 6-inch radius arm lift on a diesel platform requires a qualified suspension shop. Professional installation is required.

What warranty does this kit carry?
BDS suspension components carry the BDS No-Fine-Print Warranty. FOX 2.5 PE shocks carry a FOX 1-year limited warranty.

Verified Fitment