BILSTEIN shock absorber (24-277310) restores factory damping characteristics by controlling spring oscillation on both compression and rebound strokes, recovering steering precision and reducing body roll. Damping configuration — for OE number: A 639 326 21 00, for OE number: 639 326 21 00, Fitting Position: Rear Axle, Shock Absorber Type: Aluminium — is tuned to the original suspension geometry so spring rates and ride height are unaffected, preserving the manufacturer's comfort and handling balance. Mounting dimensions, piston diameter, and stroke length replicate the OEM unit on MERCEDES-BENZ, MERCEDES-BENZ (FJDA) applications, allowing a straight-swap installation without drilling or bracket modification. Supersedes manufacturer part numbers: 203203, 2320G, 311 646, 311 647 and 14 more. BILSTEIN dampers are gas-pressure charged, zero-leakage tested on a servo-hydraulic rig, and carry a 2-year unlimited-mileage warranty against manufacturing defects. Shock absorbers gradually lose damping force over time and should be inspected at 50,000 miles and replaced by 80,000–100,000 miles — even if they are not visibly leaking, internal valve wear reduces their effectiveness. Warning signs include excessive body roll in corners, nose-dive under braking, rear-end squat during acceleration, uneven tyre wear, and a bouncy or floaty ride — a simple bounce test (push down on each corner and release) can reveal weak dampers. Shock absorber replacement is an intermediate DIY task that requires spring compressors (for strut-type assemblies), a torque wrench, and penetrating oil for corroded fasteners — allow 2–3 hours per axle. When selecting shock absorbers, match the damper type (twin-tube, monotube, or gas-pressurised) to the original specification — upgrading to a different type can alter ride height and handling characteristics. Always replace shock absorbers in pairs (both sides of the same axle) to maintain balanced handling, and have the wheel alignment checked afterwards — worn dampers often allow geometry to drift out of specification. Every part is dispatched with tracked delivery and a 14-day money-back guarantee with hassle-free returns.

BILSTEIN, founded in 1873 in Ennepetal, Germany, is a premium manufacturer of monotube shock absorbers and suspension components, part of thyssenkrupp. BILSTEIN specialises in high-performance gas-pressure shock absorbers, coilovers, lift kits, and electronic damping systems. As the OE suspension supplier to BMW, Mercedes-AMG, Porsche, and Ford Performance, BILSTEIN represents the highest tier of damping technology. From professional motorsport to luxury touring, BILSTEIN delivers superior handling, comfort, and durability that discerning drivers and performance enthusiasts demand.