Bilstein 21-030505 Suspension Strut Cartridge - Front
OE Quality 60-Day Returns
Bilstein
 B4 OE Replacement

Bilstein 21-030505 Suspension Strut Cartridge - Front

Brand Bilstein 21-030505
Position Front
Boot Included No
Finish Black paint
Internal Design Twintube
Lower Mount Type Housing
Series B4 oe replacement
Title Bilstein shock absorbers
Upper Mount Type Stem
Product line B4 OE Replacement
Fits BMW · 21 vehicles

OE replacement. Restores original ride quality while meeting or exceeding OE standards.

Twintube design. Helps maintain consistent damping for smooth, controlled handling.

Black paint finish. Adds a clean protective coating to the strut cartridge.

Cross-references KYB 364021, 31 30 1 133 438 and 31 32 1 131 071 for the same application. See all 9.

$123.00Free shipping
In stock · usually ships same day before 1pm CST
Step 1 — Confirm fitment
Free return shipping if it doesn't fit when you check fitment here first.

Select your vehicle to confirm fitment
Verify this part fits before purchasing — free returns if it doesn't
Step 2 — Quantity
Suspension Strut Cartridges are typically replaced in pairs, axle by axle.
Order total $123.00
Free shipping to the continental U.S.
Free returns within 60 days if it doesn't fit when fitment is verified.
Not what you need? See all Suspension Strut Cartridge options

Bilstein B4 OE Replacement Front Strut Cartridge

The Bilstein B4 OE Replacement suspension strut cartridge is engineered to restore original ride quality and handling on select BMW 3 Series models. Built to meet or exceed OE standards, this front cartridge is a direct-fit replacement for drivers who want factory-style performance with Bilstein quality.

  • Bilstein B4 OE Replacement series for OE-style ride restoration
  • Front suspension strut cartridge for select BMW applications
  • Twintube internal design for controlled damping response
  • Black paint finish for corrosion-resistant appearance
  • Upper mount type: stem; lower mount type: housing
  • Boot not included

Product Line Details

Bilstein B4 OE Replacement dampers are built for drivers who want to return the vehicle’s suspension behavior to original specifications. This line focuses on maintaining factory ride comfort and handling balance while using Bilstein’s established damper engineering for consistent performance on the road.

Fitment

  • Fits 1987-1993 BMW 325i, front.
  • Fits 1991-1992 BMW 318i, front.
  • Fits 1991 BMW 318is, front.
  • Fits 1987-1991 BMW 325is, front.
  • Fits 1984-1987 BMW 325e, front.
  • Fits 1986-1987 BMW 325es, front.

What This Part Helps Address

  • Excessive front-end bounce or oscillation
  • Reduced steering response from worn suspension damping
  • Uneven ride quality compared with factory behavior
  • Noisy or loose-feeling front suspension performance caused by aging struts
  • Loss of control and stability during normal driving

Installation Notes

Verify the vehicle’s front suspension configuration before ordering. This cartridge uses a stem upper mount and housing lower mount, so the existing strut assembly should be inspected for wear, damage, and proper serviceability during replacement. Part number 21-030505 is also referenced for this application, and this part cross-references KYB 364021 for the same application.

Quality Assurance

Bilstein B4 OE Replacement parts are manufactured to meet or exceed OE standards for fit and function. Part number 21-030505 is built as an OE-style replacement for restoring original suspension performance on compatible BMW 325i, 318i, 318is, 325is, 325e, and 325es front applications.

Related reading

This part fits 21 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelSubmodelBody TypePositionNotes
1993BMW325iBase—FrontB4 OE Replacement
1992BMW318iBaseConvertibleFrontB4 OE Replacement
1992BMW325iBaseConvertibleFrontB4 OE Replacement
1991BMW318iBase—FrontB4 OE Replacement
1991BMW318isBase—FrontB4 OE Replacement
1991BMW325iBase—FrontB4 OE Replacement
1991BMW325isBase—FrontB4 OE Replacement
1990BMW325iBase—FrontB4 OE Replacement
1990BMW325isBase—FrontB4 OE Replacement
1989BMW325iBase—FrontB4 OE Replacement
1989BMW325isBase—FrontB4 OE Replacement
1988BMW325iBase—FrontB4 OE Replacement
1988BMW325isBase—FrontB4 OE Replacement
1987BMW325eBase—FrontB4 OE Replacement
1987BMW325esBase—FrontB4 OE Replacement
1987BMW325iBase—FrontB4 OE Replacement
1987BMW325isBase—FrontB4 OE Replacement
1986BMW325eBase—FrontB4 OE Replacement
1986BMW325esBase—FrontB4 OE Replacement
1985BMW325eBase—FrontB4 OE Replacement
1984BMW325eBase—FrontB4 OE Replacement
Directly replaces or cross-references 9 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
KYB — 36402131 30 1 133 43831 32 1 131 07131 32 1 133 56031 32 1 135 63531 32 1 135 892100 590F4-PNE-3050-BEPNE-3050