FCS Q4023 Air Suspension Spring - Rear Left

FCS Q4023 Rear Left Air Suspension Spring

The FCS Q4023 is a rear left air suspension spring for BMW models equipped with rear air leveling. It is built for direct-fit replacement use on the specified 1999-2003 BMW 5 Series applications, including BMW 525i, BMW 540i, and BMW 528i.

Use this FCS air suspension spring when servicing the rear left corner on a BMW 525i, BMW 540i, or BMW 528i with rear air leveling. The FCS Q4023 is listed for the exact vehicle and position combinations below.

Key Features

• Rear left air suspension spring for BMW rear air leveling systems
• Direct application coverage for 1999-2003 BMW 5 Series fitments
• Fits BMW 525i, BMW 540i, and BMW 528i applications listed below
• FCS part number Q4023 for catalog and service reference
• Position-specific replacement for the rear left suspension corner

Vehicle Fitment

• Fits 2001-2003 BMW 525i, rear left, with rear air leveling; FCS
• Fits 1999-2003 BMW 540i, rear left, with rear air leveling; FCS
• Fits 1999-2000 BMW 528i, rear left, with rear air leveling; FCS

What It Helps Address

• Rear suspension sag at the left rear corner
• Uneven ride height on air-leveling equipped BMW 5 Series models
• Air spring wear that affects rear suspension support
• Loss of proper rear stance on the vehicle
• Service replacement for a failed rear left air suspension spring

Installation Notes and Tips

Confirm the vehicle is equipped with rear air leveling before ordering or installation. Match the rear left position exactly, since this part is not listed for other corners. Verify the model year and trim against the fitment table for BMW 525i, BMW 540i, and BMW 528i applications. Part number Q4023 should be used as the primary catalog reference during service lookup.

Quality Assurance

FCS Q4023 is cataloged as a position-specific suspension replacement for the listed BMW applications. This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.