{"product_id":"caterpillar-5j-5020-seal","title":"Caterpillar 5J-5020 Seal","description":"\u003cdiv\u003e\u003cp\u003eCaterpillar 5J-5020 is a two-piece piston seal assembly for CAT hydraulic cylinders, cataloged as 5J-5020 (5J5020) and used on AD40, AD45, AD45B, AD55, AD55B, AD60, AD63, and AE40 machines. This piston seal kit provides the sealing surfaces between the cylinder bore and the piston to help contain hydraulic pressure and minimize leakage across the stroke. The two-piece design facilitates installation and replacement in tight cylinder cavities, aligning with Caterpillar service practices for the listed models. Listings across CAT parts catalogs and aftermarket suppliers describe it as a piston seal assembly (often noted as 5J-5020 or 5J5020) and, in some references, as a Seal A variant. Use of this seal is part of cylinder maintenance to restore sealing performance in heavy equipment hydraulic systems that power these CAT cylinders.\u003c\/p\u003e\u003c\/div\u003e","brand":"Caterpillar","offers":[{"title":"New Surplus No Box","offer_id":51677847519534,"sku":null,"price":73.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0940\/0818\/1038\/files\/Ebay_website_image_47e02708-867a-41a3-9cea-199769beef14.jpg?v=1769568342","url":"https:\/\/plgautomation.com\/products\/caterpillar-5j-5020-seal","provider":"PLG Automation ","version":"1.0","type":"link"}