Bilstein B3 40-231990 Rear Left Air Spring Bag/Bellow (Nearside UK, LH N/S) for BMW 5 Series E39 Touring Estate Wagon 1996-2004 – Self-Levelling/Leveling SLS Air Ride Suspension Pneumatic Spring OE-Quality Direct Fit Replacement

Bilstein B3 40-231990 Left Rear Pneumatic Spring for BMW E39 5 Series Touring

Restore the correct stance and smoothness of your E39 estate with the Bilstein B3 40-231990 left rear air ride spring. This UK nearside rear pneumatic bellows is a like-for-like replacement for the factory self levelling rear spring on BMW 5 Series Touring models from 1996 to 2004. If the back end sags, drops overnight, sits uneven, or the compressor runs constantly, this quality Bilstein unit is the proven cure.

We run these B3 springs on our own cars and have installed them for countless customers. Feedback is consistently positive for ride comfort, stability when loaded, and dependable level control. It fits properly, seals correctly and brings the car back to the height and composure you expect from a BMW.

Key benefits

• Exact-fit left rear air spring for E39 Touring with rear level control
• Brings back correct ride height and consistent handling
• Quiet, reliable operation with stable counter-pressure in the bellows
• Excellent comfort on motorways and B-roads, empty or fully loaded
• Ideal fix for leaks, perished rubber, cracks or sagging at the back
• Matches vehicles with standard or sport chassis settings
• Designed to work with the original compressor and level sensors

Fitment details

Position: Rear axle left - UK passenger side
Design: Air spring bellows - pneumatic suspension bag
Vehicle: BMW 5 Series E39 Touring estate - with rear self levelling system

Model and year coverage

BMW 5 Series Touring E39 09/1996 to 06/2004, including:

• Petrol: 520i, 523i, 525i, 528i, 530i, 540i
• Diesel: 520d, 525d, 525tds, 530d

Note: For estate Touring models only. Not suitable for E39 Saloon.

Part numbers

Part number: BILSTEIN-40-231990 / 40-231990
EAN: 4025258739768
UPC: 651860741031

Opposite side

Need the right-hand rear as well for a matched pair? Order the corresponding rear offside spring: Bilstein 40-232003.

Why Bilstein for your E39 Touring

• OE-quality construction for durability and long service life
• Consistent height control under passengers, luggage or towing
• Direct replacement that retains genuine BMW driving feel

Symptoms this solves

• Rear end low on one side - rear left dropping
• Vehicle sinks overnight - car sits down when parked
• Air compressor running too often or too long
• Harsh ride, uneven stance, suspension warning messages

Installation

Professional fitting recommended. For supply and install, contact MJ Modifications, Warwickshire. Request a fitting quote at info@mjmodifications.co.uk. For best results, replace rear air springs in pairs.

Compatibility check before dispatch

We can confirm suitability before shipping. Provide your UK registration or the last 7 characters of your VIN at checkout and we will verify fitment for your specific E39 Touring.

Search-friendly terms

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