We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Unity rear right air spring, black rubber bellows with metal end caps

Unity

Unity Rear Right Air Spring 15-525402

SKU CH-D7J0-RQPSD

Replaces the rear right air spring on 1999-2003 BMW 525i, 528i and 540i models

  • Restores factory ride height on 1999-2003 BMW 5-Series
  • 50+ years of aftermarket suspension manufacturing experience
  • Elite Suspension Line air spring for air-ride systems
  • Direct replacement for rear right position on 525i, 528i, 540i
  • New Unity part number 15-525402 ensures correct fit

Unity Rear Right Air Spring 15-525402

This new replacement air spring restores the rear right corner of the air suspension system on compatible BMW models. It is built for owners of the 2001 to 2003 BMW 525i, 1999 to 2000 BMW 528i, and 1999 to 2003 BMW 540i who need to regain factory ride quality. The part is designed for a trouble-free installation that returns the vehicle to a safe and comfortable air ride.

Replaces worn or leaking original air springs

Vehicles showing sagging ride height, compressor over-cycling, or harshness over bumps benefit from this direct-fit unit. The upgrade is worth it when the original rubber bellows have cracked or the internal piston seal has failed, causing the corner to drop overnight. It restores proper load levelling without requiring conversion to coil springs or modification of the air lines.

Maintains consistent pressure under continuous

The air spring is engineered to withstand repeated inflation and deflation as the suspension reacts to changing loads and road surfaces. It resists heat buildup and abrasion during extended highway runs or frequent stop-and-go traffic, preserving ride height stability over time. The construction supports long-lasting reliability through daily suspension actuation.

Highlights

  • Restores factory ride height on 1999-2003 BMW 5-Series
  • 50+ years of aftermarket suspension manufacturing experience
  • Elite Suspension Line air spring for air-ride systems
  • Direct replacement for rear right position on 525i, 528i, 540i
  • New Unity part number 15-525402 ensures correct fit

Specifications

BrandUNITY

Questions about this item

Will this 15-525402 air spring fit the rear right corner of my 2001 BMW 525i without modification?

Yes, it is listed as a direct replacement for the 2001-2003 BMW 525i rear right air suspension position

What is the correct procedure for installing this Unity air spring on a 1999 BMW 528i, and which step is most often missed?

Depressurise the system, remove the old unit, fit the new spring, reconnect the air line, then re-pressurise and check for leaks; the step most often missed is fully depressurising before disconnecting the old line

What maintenance does the 15-525402 rear right air spring need on a 2003 BMW 540i to maximise service life?

Inspect the rubber bellows for cracks or leaks during each major service; replace immediately if air loss or uneven ride height appears

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.