BDS 6-Inch Lift Kit — Dodge Ram 2500 / Ram 3500 SKU: BDS681FS | Dodge Ram 2500 / Ram 3500 2008 | 4WD | Diesel | 6" Front / 4" Rear | FOX 2.0 Performance Series | Leaf Springs Rear | 4-Inch Axle

A complete 6-inch suspension lift kit engineered for the 2008 Dodge Ram 2500 and Ram 3500 diesel 4WD — configured for the 4-inch rear axle with leaf spring rear. Diesel-specific progressive rate Pro-Ride coil springs provide the 6-inch front lift. BDS-engineered lower control arms are longer than stock to rotate the axle for proper alignment, paired with a relocation mounting bracket to flatten the upper control arm angle. Forged drop pitman arm and track bar bracket correct steering geometry. The rear uses progressive rate multi-leaf springs for a 4-inch rear lift with extended U-bolts. FOX 2.0 Performance Series shocks front and rear. Clears up to 36-inch tires.

Before ordering: This kit fits the 2008 Dodge Ram 2500 and Ram 3500 diesel 4WD only. You must measure your rear axle tube diameter before ordering — this kit is configured for the 4-inch axle. Two axle diameters exist on this generation Ram and the wrong selection results in an incompatible rear kit. This kit is diesel-specific — gas engine models are not supported. If your truck's steering gear box has been replaced and the sector shaft diameter measures approximately 1-1/2 to 1-5/8 inches, you must add BDS082404 to your kit. Welding equipment, a cut-off wheel, and a grinder/sanding disc are required specialty tools — confirm your installer has these before scheduling.

Required separately (conditional):

• BDS082404 — Required if steering gear box has been replaced and sector shaft diameter is approximately 1-1/2 to 1-5/8 inches
• U-bolt 4068 — some 4-inch axle models with dual overloads may require this; confirm before ordering
• Transfer case drop kit (if driveline vibration occurs): 122605 (06–08 Diesel Auto) or 122606 (03–13 Diesel Auto with OE mount PN 52121938AA). Auto transmission only. Alternatively, T-case index kits 122801 (auto) or 122802 (manual).

Verified Fitment

Diesel only. Gas engine models are not supported. This kit covers the 2008 model year only — for 2003–2007, see BDS236FS (3-1/2 inch axle) or BDS266FS (4-inch axle); for 2009–2013, see BDS6673FS.

Component Specifications

Lift Configuration (this SKU):

Pro-Ride Coil Springs — Front:

Control Arms:

Rear Lift — Leaf Springs:

FOX 2.0 Performance Series Shocks (front and rear):

What Is and Is NOT Included

Included — Front:

• Diesel-specific progressive rate Pro-Ride coil springs (pair)
• BDS-engineered lower control arms (pair — longer than stock)
• Upper control arm relocation mounting brackets
• Forged drop pitman arm
• Track bar relocation bracket
• Sway bar links
• Bump stops
• FOX 2.0 Performance Series front shocks

Included — Rear:

• Multi-leaf progressive rate rear springs (4-inch, 4-inch axle configuration)
• Extended U-bolts
• FOX 2.0 Performance Series rear shocks

Not included (conditional — may be required):

• BDS082404 — Required if steering gear box has been replaced and sector shaft diameter is approximately 1-1/2 to 1-5/8 inches
• U-bolt 4068 — some 4-inch axle models with dual overloads may require this
• Transfer case drop kits (if driveline vibration occurs): 122605 or 122606 (auto transmission only); or T-case index kits 122801 (auto) / 122802 (manual)

Critical Compatibility

• Rear axle measurement required — 4-inch axle configuration: This kit is built for the 4-inch axle. Two rear axle diameters exist on this generation Ram. Measure your rear axle tube before ordering. The wrong axle selection results in an incompatible rear kit.
• 4-inch axle dual overload note: Some 4-inch axle models equipped with dual overloads will require U-bolt 4068. Confirm your rear axle configuration before ordering.
• Diesel only: Diesel-specific Pro-Ride coil springs are included. Gas engine models are not supported.
• 2008 model year only: This kit is specific to the 2008 Dodge Ram 2500 and Ram 3500. For 2003–2007, see BDS236FS or BDS266FS. For 2009–2013, see BDS6673FS.
• Steering gear box sector shaft check: If the steering gear box has been replaced and the sector shaft diameter measures approximately 1-1/2 to 1-5/8 inches, BDS082404 must be added. Inspect your sector shaft before ordering.
• Transfer case drop kits: Not included and not required for standard installation. If driveline vibration occurs, 122605 (06–08 Diesel Auto) or 122606 (03–13 Diesel Auto with OE mount PN 52121938AA) apply for the 2008 model year. Auto transmission only. T-case index kits 122801 (auto) or 122802 (manual) are also available.
• 6.7L Diesel and dual rear shock kit: If also installing dual rear shock kit 122009, exhaust modification is required on 6.7L diesel models for that specific accessory.
• Welding and grinding required: Cut-off wheel or equivalent, grinder/sanding disc, and welding equipment are listed as required specialty tools. Confirm installer capability before scheduling.
• ADAS recalibration: Required after installation. All recalibration costs are the owner's responsibility.
• Tire fitment: Clears up to 36 x 12.50-inch tires. Minor trimming may be required.

Installation Notes

Professional installation is strongly recommended. This kit is rated Moderate with an estimated installation time of 8 hours. Specialty tools required: cut-off wheel or equivalent, grinder/sanding disc, pitman arm puller, and welding equipment. Confirm your installer has all required tools before scheduling.

Verify before beginning:

• Rear axle tube diameter confirmed as 4-inch
• Dual overload check (may require U-bolt 4068)
• Steering gear box replacement and sector shaft diameter check (if replaced, measure — if 1-1/2 to 1-5/8 inches, add BDS082404)
• Transmission and transfer case type (relevant to T-case drop kit selection if needed)
• Installer has welding equipment, cut-off wheel, and grinder
• ADAS recalibration appointment scheduled

Professional alignment is required after installation. Refer to the current BDS Suspension installation instructions for SKU BDS681FS for complete procedures, torque specifications, and component-specific instructions.

The Obsidian Take

The BDS681FS is the 4-inch axle companion to BDS680FS for the 2008 Dodge Ram 2500/3500 diesel — same platform, same lift heights, same FOX 2.0 shocks, same 8-hour installation estimate, same specialty tool requirements. The only substantive difference is the rear axle diameter. Measure before ordering. If you have the 4-inch axle with dual overloads, also confirm whether U-bolt 4068 is required — that's the one additional check specific to the 4-inch axle over the 3-1/2 inch variant. Everything else carries over identically from BDS680FS.

This Product Is For You If

• You own a 2008 Dodge Ram 2500 or Ram 3500 diesel 4WD with a confirmed 4-inch rear axle.
• Your truck's steering gear box is factory original, or if replaced, the sector shaft is not in the 1-1/2 to 1-5/8 inch range (or you will add BDS082404).
• You want the leaf spring rear option for reduced axle wrap, improved stability, and maintained factory payload ratings.
• You want 6 inches of front lift and 4 inches of rear lift with FOX 2.0 Performance Series shocks.
• You want up to 36-inch tire clearance.
• Your installer has welding equipment, a cut-off wheel, and a grinder.

This Product Is Not For You If

• You have not measured your rear axle tube diameter — wrong axle selection produces an incompatible kit.
• Your rear axle is a 3-1/2 inch axle — see SKU BDS680FS.
• Your truck has a replaced steering gear box with a sector shaft diameter of approximately 1-1/2 to 1-5/8 inches and you have not added BDS082404.
• Your Ram has a gas engine.
• Your Ram is not a 2008 model year — see BDS236FS/BDS266FS for 2003–2007; see BDS6673FS for 2009–2013.
• Your installer does not have welding equipment or a cut-off wheel.
• You want the block rear option — see the block kit variant.
• You want NX2 Nitro Series shocks — see the NX2 variant.
• You want FOX 2.5 Performance Elite Series shocks — see the FOX 2.5 variant.

Product Family Reference

Common Questions

What is the difference between BDS681FS and BDS680FS?
The only difference is rear axle configuration. BDS681FS is for the 4-inch axle. BDS680FS is for the 3-1/2 inch axle. All other components, lift heights, shock option, specialty tool requirements, and installation time are identical. Measure your rear axle tube before ordering.

I have a 4-inch axle with dual overloads — do I need a different U-bolt?
Some 4-inch axle models with dual overloads require U-bolt 4068. Inspect your rear axle and spring configuration and confirm with BDS or your installer before ordering.

Does this kit fit 2007 or 2009 Ram models?
No. This kit is specific to the 2008 model year only. For 2003–2007, see BDS236FS or BDS266FS. For 2009–2013, see BDS6673FS.

What if I have driveline vibration after installation?
For the 2008 model year, the applicable transfer case drop kits are 122605 (06–08 Diesel Auto) or 122606 (03–13 Diesel Auto with OE mount PN 52121938AA). Both are auto transmission only. T-case index kits 122801 (auto) or 122802 (manual) are also available.

What is the sector shaft check?
If the steering gear box has been replaced and the sector shaft diameter measures approximately 1-1/2 to 1-5/8 inches, BDS082404 must be added to the kit. Inspect your sector shaft before ordering.

Does this kit fit the gas Ram?
No. The Pro-Ride coil springs are diesel-specific.

Does ADAS need to be recalibrated after installation?
Yes. All ADAS sensors require professional recalibration after installation. All recalibration costs are the owner's responsibility.

Manufacturer Data Disclaimer

Fitment, specification, included-component, and installation data for this kit are sourced from BDS Suspension manufacturer documentation and OFAS-verified product data current as of publication. Manufacturer specifications and included components are subject to change without notice; confirm current documentation for this SKU at the time of purchase.

Required Legal, Warning, Fitment, and Return Notices

ADAS Recalibration Warning: This kit alters vehicle ride height and suspension geometry. All advanced driver assistance system (ADAS) sensors require professional recalibration after installation. Schedule recalibration at an authorized dealer or certified ADAS service center. All recalibration costs are the owner's responsibility.

Installation Warning: Professional installation is strongly recommended. Welding equipment, a cut-off wheel or equivalent, and a grinder/sanding disc are required specialty tools. Confirm installer capability before scheduling. A professional wheel alignment is required after installation.

Rear Axle Warning: Two rear axle tube diameters exist on this generation Ram. Measure your rear axle tube before ordering. Ordering the wrong axle configuration produces an incompatible rear kit.

Steering Gear Box Warning: If the steering gear box has been replaced and the sector shaft diameter measures approximately 1-1/2 to 1-5/8 inches, BDS082404 must be added to this kit. Inspect your sector shaft before ordering.

Tire Fitment Notice: Up to 36 x 12.50-inch tires are supported. Trimming may be required. Buyer is responsible for verifying tire and wheel clearance for their specific vehicle and build.

California Proposition 65 Warning: This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.

Return Policy: All returns require prior authorization from Obsidian Forged Auto Supply — do not ship any product back without a Return Merchandise Authorization (RMA). To request an RMA, contact OFAS at Support@obsidianforgedautosupply.com or 469-407-7538 (Monday–Friday 9am–5pm CST, Saturday 9am–3pm CST) with your order number, product SKU, return reason, and photos. Return requests must be submitted within 90 days of delivery. To qualify, the product must be new, unused, uninstalled, complete with all hardware and included components, and in original manufacturer packaging. Do not write on, tape to, or place shipping labels directly on the manufacturer's product box. Return shipping is the customer's responsibility in all cases. Non-defective returns may be subject to a 15% restocking fee. No restocking fee applies when OFAS shipped the wrong item or the return is due to a verified defect or approved damage claim. Some products — including special-order, electrical, and installed items — may be non-returnable. Return eligibility is also subject to applicable manufacturer and supplier return requirements. Approved refunds are issued to the original payment method within approximately 10 business days of the warehouse receiving and processing the returned product. For damaged, missing, or incorrect shipments, contact OFAS within 48 hours of delivery, retain all packaging, and do not install the product.