BMW X5 X6 Front Lower Rearward Control Arm Set 31126851691 31126851692 13-19

Replacing both control arms together with genuine BMW parts offers several compelling advantages: Safety and performance:
(1) Control arms wear at similar rates—if one has failed, the other is typically close behind, especially on high-mileage vehicles,
(2) Matched genuine pair ensures identical suspension geometry on both sides for balanced handling, braking, and stability,
(3) Eliminates subtle handling imbalances that can occur when mixing worn and new components. Financial advantages:
(1) One alignment vs. two—mandatory wheel alignment costs $150-250 each time; replacing both sides now saves that cost later,
(2) One labor charge—replacing both arms in one service session saves 1-2 hours of labor charges vs. two separate visits,
(3) Overall savings—total cost of two separate services (parts + labor + alignment x2) significantly exceeds the cost of one comprehensive service. BMW technician recommendation: Most BMW-certified technicians strongly advise replacing both sides simultaneously on vehicles with 80,000+ miles. The genuine parts investment plus single service event is significantly more economical than two separate repair visits within a 6-12 month period

This is a critical verification step before ordering. These systems require different control arm specifications and this part will NOT fit those vehicles correctly. How to check:
(1) iDrive menu—Navigate to Vehicle Settings > Driving Experience > look for "Electronic Damper Control" or "Dynamic Drive" settings,
(2) Build sheet—Check your vehicle's original build sheet (obtainable from BMW dealer with VIN) for option codes: S223A (Electronic Damper Control), S2VH (Dynamic Driving Package),
(3) Physical inspection—Vehicles with electronic drive dynamics have additional wiring harnesses and sensors visible at the control arm area,
(4) BMW dealer VIN lookup—Most reliable method: provide your VIN to a BMW dealer parts department who can confirm exact correct part numbers,
(5) Door jamb sticker—May list option codes that indicate these systems. If equipped: You need different part numbers designed for electronically controlled suspension. Installing incorrect control arms on these vehicles compromises the suspension system function and safety. If uncertain: Always verify with BMW dealer using VIN before ordering—this 2-minute step prevents costly mistakes

BMW periodically updates part numbers through their supersession system when manufacturing improvements are made. What supersession means: The original part number may have been updated to an improved version. When you order through BMW dealer or authorized genuine parts supplier, you should receive the latest current version regardless of which historical part number you reference. How to verify current numbers:
(1) BMW dealer parts lookup—Provide original part numbers 31126851691/692 and request confirmation of current active numbers,
(2) TecDoc or ETK lookup—BMW's electronic parts catalog (ETK) shows current active and superseded numbers,
(3) Authorized BMW parts suppliers—Will automatically supply the latest version. Important: Whether you receive parts labeled 31126851691/692 or a superseded number, the fit and function will be identical or improved for your F15/F85/F16/F86 chassis. Recommendation: When ordering, reference both the original part numbers AND your VIN/chassis code to ensure receiving the most current correct genuine parts for your specific vehicle.

While your vehicle is on the lift with front suspension disassembled for both control arm replacements, this is the ideal time for comprehensive front suspension inspection. Strongly recommended inspection items:
(1) Upper control arms—Check for bushing wear, cracks, or play; if worn, replace simultaneously to avoid repeat labor charges,
(2) Ball joints—Inspect for play, torn boots, or wear; often integral with control arm but worth confirming,
(3) Stabilizer bar links (sway bar links)—Check for worn bushings or broken links; inexpensive to replace while already disassembled,
(4) Tie rod ends—Inspect inner and outer for play or worn boots; alignment is required regardless so this is ideal timing,
(5) Wheel bearings—Inspect for play or noise while wheel is off vehicle,
(6) Brake components—With wheels removed, inspect pads, rotors, and calipers on both sides. Cost-efficiency strategy: Addressing all identified worn suspension components in one service session saves significant labor costs versus multiple separate services. BMW dealer recommendation: Request a comprehensive suspension inspection report when having control arms replaced. Identifying and addressing all worn components simultaneously—with one alignment covering everything—is the most economical and efficient approach for high-mileage F15/F16 vehicles.