{"product_id":"bilstein-21-030512-suspension-strut-cartridge-front","title":"Bilstein 21-030512 Suspension Strut Cartridge - Front","description":"\u003ch2\u003eBilstein B4 OE Replacement Suspension Strut Cartridge Overview\u003c\/h2\u003e\u003cp\u003eThe Bilstein shock absorbers part number 21-030512 offer a reliable suspension upgrade for BMW models including the 528e, 533i, 535i, 535is, and 635CSi. Designed as a direct replacement, this suspension strut cartridge restores original ride quality and handling characteristics.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eDirect OE replacement for precise fit and function\u003c\/li\u003e\n\u003cli\u003eTwintube internal design for consistent damping performance\u003c\/li\u003e\n\u003cli\u003eBlack paint finish for corrosion resistance\u003c\/li\u003e\n\u003cli\u003eLower mount type: housing for secure installation\u003c\/li\u003e\n\u003cli\u003eUpper mount type: stem for compatibility with factory mounts\u003c\/li\u003e\n\u003cli\u003eBoot not included\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eDetailed Product Description\u003c\/h2\u003e\u003cp\u003eThe Bilstein B4 OE Replacement suspension strut cartridge (part number 21-030512) features a twintube internal design that provides reliable and consistent damping performance suitable for daily driving and maintaining factory ride comfort. The black paint finish offers protection against corrosion, extending the service life of the strut. This cartridge is engineered with a housing lower mount and a stem upper mount, ensuring compatibility with the original mounting points on BMW 528e, 533i, 535i, 535is, and 635CSi models. The absence of a boot means the strut is designed to work with existing protective components on the vehicle.\u003c\/p\u003e\u003ch2\u003eAbout the B4 OE Replacement Product Line\u003c\/h2\u003e\u003cp\u003eThe Bilstein B4 OE Replacement line is designed to meet or exceed original equipment specifications, providing a cost-effective solution for restoring suspension performance. This product line focuses on delivering reliable damping and ride comfort by replicating the original shock absorber design, making it suitable for drivers seeking to maintain factory handling characteristics without upgrading to performance variants.\u003c\/p\u003e\u003ch2\u003eCommon Applications and Issues Addressed\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eRestores factory ride comfort and handling on BMW 528e, 533i, 535i, 535is, and 635CSi\u003c\/li\u003e\n\u003cli\u003eReplaces worn or leaking suspension struts\u003c\/li\u003e\n\u003cli\u003eEliminates excessive body roll and instability\u003c\/li\u003e\n\u003cli\u003eImproves vehicle control and braking response\u003c\/li\u003e\n\u003cli\u003eReduces noise and vibration from damaged shocks\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eInstallation Notes and Tips\u003c\/h2\u003e\u003cp\u003eInstallation of the Bilstein 21-030512 suspension strut cartridge requires removal of the original strut assembly. Ensure the vehicle is securely lifted and supported before beginning work. Since the boot is not included, inspect existing protective components and replace if necessary to prevent premature wear. Proper torque specifications should be followed for both upper stem and lower housing mounts to maintain safety and performance.\u003c\/p\u003e\u003ch2\u003eQuality Assurance and Warranty\u003c\/h2\u003e\u003cp\u003eBilstein B4 OE Replacement shock absorbers are manufactured to meet strict quality standards, ensuring durability and consistent performance. While specific warranty details are not provided here, Bilstein products typically come with a limited warranty covering defects in materials and workmanship. Refer to official Bilstein documentation for exact warranty terms.\u003c\/p\u003e","brand":"Bilstein","offers":[{"title":"Default Title","offer_id":51953730191541,"sku":"BBGL-21-030512","price":98.21,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0628\/1442\/1173\/files\/B5_21030512_Fro.jpg?v=1775061573","url":"https:\/\/www.partcatalog.com\/products\/bilstein-21-030512-suspension-strut-cartridge-front","provider":"PartCatalog","version":"1.0","type":"link"}