BDS 6-Inch Radius Arm Lift Kit | Rear Air Ride | FOX 2.0 Shocks | Ram 3500 4WD Diesel 2013–2018 | SKU: 2106FS

The BDS 2106FS is a 6-inch radius arm front lift kit with FOX 2.0 Performance Series shocks for the 2013–2018 Ram 3500 4WD diesel equipped with factory rear air ride suspension. This is the air ride-specific variant — it includes the rear brackets required to integrate with the factory air ride system and preserve the factory load-leveling function at lifted height. 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 front lift at the correct spring rate for the diesel engine weight.

This kit has four hard fitment splits before it applies to your truck.

First — rear suspension: this kit is built specifically for Ram 3500 trucks with factory rear air ride. If your Ram 3500 does NOT have factory rear air ride, order 2104FS (FOX 2.0) or 2104FPE (FOX 2.5 PE) instead. Running this kit on a non-air-ride truck installs brackets with no system to connect to.

Second — generation: the 2013–2018 Ram 3500 is the DS platform. The 2019 and newer Ram 3500 is the DT platform — order 1724FS for the DT platform with air ride.

Third — engine: diesel-tuned coil springs. Ram 3500 gas requires different spring tuning.

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

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

Component Specifications

What Is and Is NOT Included

Critical Compatibility

Four fitment confirmations required before ordering.

Not sure if your Ram 3500 has factory rear air ride? Text (469) 407-7538 before ordering.

DS vs. DT Generation + Air Ride Variant Reference — Ram 3500 Diesel

Tire Clearance

At 6 inches of front lift on the 2013–2018 Ram 3500 diesel platform, typical fitment runs 37–40-inch tires depending on wheel offset and backspacing. Tires at the larger end of this range may require trimming or additional modifications. Confirm maximum tire diameter and wheel specifications with your wheel and tire supplier before ordering.

Installation Notes

Professional installation is required — air ride experience mandatory. A 6-inch radius arm lift with factory air ride integration requires a qualified suspension shop experienced specifically with Ram air ride systems. This is not a standard lift installation — the air ride bracket integration adds complexity. Do not attempt DIY installation.

Full front-end alignment is mandatory after installation. Do not drive on public roads before alignment is completed. Running a lifted diesel truck without post-installation alignment causes accelerated tire wear, steering pull, and handling instability under tow.

Driveline inspection is mandatory at 6-inch lift. At 6 inches, inspect driveshaft angles and U-joint operating angles after installation. Driveshaft modification may be required depending on your specific truck's configuration — confirm with your installer before the job begins.

Factory air ride system verification is mandatory after installation. After the lift is installed, verify that the factory air ride load-leveling function operates correctly at lifted height. If the air ride system does not function correctly after installation, do not drive the truck — return to your installer before road use.

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 2.0 shocks to complete the manufacturer-recommended break-in period before aggressive off-road or heavy towing use.

Text (469) 407-7538 to confirm air ride configuration, generation, engine, and drivetrain before ordering.

The Obsidian Take

The BDS 2106FS is the correct kit for the 2013–2018 Ram 3500 4WD diesel owner who has factory rear air ride and wants 6 inches of front lift without sacrificing the load-leveling function that makes the air ride system worth having. The air ride-specific brackets in this kit are what separate it from the standard 2104FS and 2104FPE — without them, the factory air ride system cannot operate correctly at lifted height. If your truck tows heavy and relies on the air ride to maintain level stance under load, this is the only variant in the DS Ram 3500 lineup that preserves that capability.

If your Ram 3500 does not have factory rear air ride, this kit installs brackets with nothing to connect to — order 2104FS for FOX 2.0 or 2104FPE for FOX 2.5 PE. Both deliver the same 6-inch front lift and radius arm geometry correction on the DS platform without the air ride integration hardware.

If your Ram 3500 is a 2019 or newer DT platform with air ride, the DS kit does not apply — order 1724FS for the DT air ride application.

At 6 inches of lift with diesel towing loads and air ride integration, this installation has more complexity than a standard radius arm lift. Confirm your installer has Ram air ride experience before the job starts — the air ride system verification after installation is not optional.

DS platform, diesel, 4WD, factory air ride confirmed — the 2106FS is the complete, correctly-integrated solution for the Ram 3500 that tows as hard as it looks.

Common Questions

How do I know if my Ram 3500 has factory rear air ride?
The factory rear air ride system uses air bags at the rear axle in place of or in addition to conventional leaf springs, with a compressor that automatically levels the truck under load. Check your window sticker or build sheet for the factory air suspension option — it is typically listed as "Rear Load Leveling Air Suspension." You can also visually inspect the rear axle area for air bags. Text (469) 407-7538 if you need help confirming before ordering.

What happens if I install this kit on a Ram 3500 without air ride?
The air ride-specific brackets in this kit are designed to integrate with the factory air ride system. Installing them on a truck without air ride adds hardware with no system to connect to — the brackets serve no function and the kit is not the correct application. Order 2104FS or 2104FPE for non-air-ride DS Ram 3500.

What is the difference between 2106FS and 2104FS?
Both kits fit the 2013–2018 Ram 3500 4WD diesel and deliver 6 inches of front lift via the same BDS radius arm system. The difference is rear suspension integration — 2106FS includes air ride-specific brackets for trucks with factory rear air ride. 2104FS is for trucks without factory rear air ride. If you have air ride, 2106FS is required to preserve load-leveling function at lifted height.

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?
Front lift is delivered via the radius arm upgrade and diesel-tuned coil springs. The factory rear air ride system handles rear suspension at lifted height via the included air ride-specific integration brackets. Confirm rear ride height expectations with your installer before ordering.

What tire size fits at 6-inch lift?
Typical fitment on the 2013–2018 Ram 3500 diesel at 6-inch lift runs 37–40-inch tires depending on wheel offset and backspacing. Tires at the larger end of this range may require trimming or additional modifications. Confirm maximum tire diameter and wheel specs with your wheel and tire supplier before ordering.

What warranty does this kit carry?
BDS suspension components carry the BDS No-Fine-Print Warranty. FOX 2.0 shocks carry a FOX 1-year limited warranty.

Verified Fitment