BDS 6-Inch Lift Kit | FOX 2.0 Shocks | Leaf Springs + 3.5-Inch Axle Block | Ram 2500/3500 4WD Gas 2008 Only | SKU: 686FS

The BDS 686FS is a 6-inch lift kit with FOX 2.0 Performance Series shocks for the 2008 Ram 2500 and Ram 3500 SRW 4WD gas — 2008 only. Front lift is delivered via 2008-specific gas-tuned coil springs and geometry-correct radius arm correction brackets. Rear lift is matched via replacement leaf springs and 3.5-inch axle blocks. Every component in this kit is engineered specifically for the 2008 Ram HD gas platform — 2007 and earlier use different geometry, and 2009 and newer use a different platform entirely.

Before ordering — confirm the axle block height for your configuration. There are two 6-inch kits for the 2008 Ram 2500/3500 gas: 686FS uses a 3.5-inch rear axle block and 687FS uses a 4-inch rear axle block. The correct axle block height depends on your cab style and configuration. Text (469) 407-7538 to confirm which is correct before ordering.

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

First — year: 2008 only. Not 2007. Not 2009. Confirm your model year exactly before ordering.

Second — engine: gas-tuned coil springs. Ram 2500/3500 diesel requires a different kit — 680FS (3.5-inch axle block) or 681FS (4-inch axle block) for 2008 diesel.

Third — drivetrain: 4WD only. 2WD is not compatible.

Fourth — axle block height: 3.5-inch (this kit) or 4-inch (687FS). Confirm before ordering.

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.

Unsure of axle block height, year, or DRW status? Text (469) 407-7538 before ordering.

2008 Ram HD Gas 6-Inch Kit Variants

Tire Clearance

At 6 inches of lift on the 2008 Ram 2500/3500 gas platform, typical fitment runs 37–40-inch tires depending on wheel offset and backspacing. Confirm maximum tire diameter and wheel specifications with your wheel and tire supplier before ordering.

Installation Notes

Professional installation is required. A 6-inch lift with leaf spring replacement requires a qualified suspension shop with experience on heavy-duty truck platforms. This is not a bolt-on leveling kit. 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 truck without post-installation alignment causes accelerated tire wear, steering pull, and handling instability.

Driveline inspection is required 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 configuration — confirm with your installer before the job begins.

Rear axle block installation. 3.5-inch axle blocks must be installed per BDS specifications. Confirm U-bolt torque specs and axle centering after installation — improperly centered axle blocks cause driveline vibration and premature U-joint wear.

Torque all fasteners to BDS specification. Torque specs are included in the BDS installation instructions. Do not estimate torque values.

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 year, axle block height, engine, and configuration before ordering.

The Obsidian Take

The BDS 686FS is the correct kit for the 2008 Ram 2500 or Ram 3500 SRW 4WD gas owner who wants 6 inches of lift with FOX 2.0 damping and a 3.5-inch rear axle block. The 2008-specific gas-tuned coil springs and radius arm brackets are engineered for this platform year — they are not interchangeable with 2007 or 2009 components.

The only variable between this kit and 687FS is the rear axle block height — 3.5 inches here, 4 inches there. That difference determines rear ride height and geometry balance for your specific cab and configuration. Ordering the wrong axle block height is the most common misorder on this platform and the kit is non-returnable once installed. Text (469) 407-7538 with your cab style and configuration before the order ships.

If your Ram HD is diesel, gas-tuned springs are not the correct tune — order 680FS or 681FS for the 2008 diesel. If your Ram HD is a 2007 or earlier or 2009 or newer, this kit does not apply. If your Ram 3500 is a Dually, confirm compatibility before ordering.

2008, gas, 4WD, SRW, 3.5-inch axle block confirmed — the 686FS is the complete, year-correct solution.

Common Questions

What is the difference between 686FS and 687FS?
Both kits fit the 2008 Ram 2500/3500 SRW 4WD gas. The only difference is the rear axle block height — 686FS uses a 3.5-inch block and 687FS uses a 4-inch block. Text (469) 407-7538 to confirm which is correct for your cab style and configuration before ordering.

Why does this kit only fit 2008 and not 2007 or 2009?
The 2008 Ram HD sits at a platform transition point with different front suspension geometry than the 2007 and earlier, and a different configuration than the 2009 and newer platform. The 2008-specific coil springs and radius arm correction brackets in this kit are not compatible with adjacent model years. Confirm your year is exactly 2008 before ordering.

My Ram is a 2008 diesel — does this kit fit?
No. The gas-tuned coil springs in this kit are not correct for the diesel engine weight. For 2008 Ram 2500/3500 SRW 4WD diesel, order 680FS (3.5-inch axle block) or 681FS (4-inch axle block).

Does this fit the Ram 3500 Dually?
Ram 3500 DRW compatibility is not confirmed for this kit. Text (469) 407-7538 before ordering if your Ram 3500 is a Dually configuration.

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 load. The inspection confirms whether your driveshaft requires modification — it is not optional at this lift height.

What tire size fits at 6-inch lift?
Typical fitment on the 2008 Ram 2500/3500 gas at 6-inch lift runs 37–40-inch tires depending on wheel offset and backspacing. 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