{"product_id":"3m-urethane-seam-sealer-08367-black-310-ml-cartridge-flexible-paintable-automotive-sealant","title":"3M Urethane Seam Sealer 08367 — Black 310 mL Cartridge, Flexible Paintable Automotive Sealant","description":"\u003cp\u003e\u003cstrong\u003e3M Urethane Seam Sealer 08367 is a single-component, black urethane sealant in a 310 mL cartridge formulated to bond to metal and painted surfaces while remaining permanently flexible.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eBuilt for automotive and RV bodywork, this high-solids urethane seam sealer fills gaps, resists shrinking and cracking, and cures to a durable, paintable finish. Unlike solvent-based products, the moisture-curing chemistry of 3M 08367 tolerates heat and humidity, adheres to bare or primed metal, and can be tooled to a featheredge or brushed smooth. Typical handling characteristics include a 10-minute working window, tack-free surface in 30–45 minutes, and full cure in 24 hours, making it a practical option for repair shops and DIY restorers.\u003c\/p\u003e\n\n\u003ch3\u003eHow will this seam sealer perform on bare or painted metal?\u003c\/h3\u003e\n\u003cp\u003eThe 3M urethane formula was developed to adhere strongly to a range of automotive substrates, including bare metal, primed panels, and factory paint. Its single-component composition simplifies application without mixing, and the cured material remains flexible to accommodate panel movement.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eAdheres to bare, primed, and painted metal surfaces\u003c\/li\u003e\n  \u003cli\u003eSingle-component — no primers or activators required for typical applications\u003c\/li\u003e\n  \u003cli\u003ePermanent flexibility reduces risk of cracks on vibrating panels\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat are the working and cure times for practical workshop use?\u003c\/h3\u003e\n\u003cp\u003e3M 08367 offers a short working window and fast surface readiness for paint, which helps speed throughput. Expect approximately ten minutes of toolable work time, a tack-free surface after 30–45 minutes, and full cure within about 24 hours under normal shop conditions.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eWork time: ~10 minutes for tooling and smoothing\u003c\/li\u003e\n  \u003cli\u003eTack-free and paintable: 30–45 minutes\u003c\/li\u003e\n  \u003cli\u003eFull cure: approximately 24 hours depending on temperature and humidity\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCan I use this sealer to fill large gaps and finish it to a smooth surface?\u003c\/h3\u003e\n\u003cp\u003eYes — the product's high solids and thick consistency are intended to fill sizable seams and joints without sagging. It can be smoothed to a feathered edge or brushed for a neat transition, then painted over once the tack-free stage is reached.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eThick, non-sagging formula fills larger voids\u003c\/li\u003e\n  \u003cli\u003eToolable to featheredge or finished with a brush\u003c\/li\u003e\n  \u003cli\u003eNon-shrinking and non-cracking after cure\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy choose a moisture-curing urethane over solvent-based seam sealers?\u003c\/h3\u003e\n\u003cp\u003eMoisture-curing urethanes like 3M 08367 cure from the surface inward using ambient humidity, which improves performance in hot or humid environments and produces a more flexible joint. Compared with older solvent-based products, urethane sealers resist drying-related shrinkage and maintain elasticity over time.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eMoisture-curing for consistent performance in varied climates\u003c\/li\u003e\n  \u003cli\u003eGreater long-term flexibility than solvent-based alternatives\u003c\/li\u003e\n  \u003cli\u003eReduced risk of cracking or separation on moving panels\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho this product is for: 3M Urethane Seam Sealer 08367 is aimed at professional collision repair shops, custom vehicle builders, RV technicians, and experienced DIYers who need a durable, paintable seam sealer that bonds to metal and painted surfaces. Choose this cartridge when you require a non-shrinking, moisture-curing urethane that can be tooled to a smooth finish, and when predictable working and cure times help keep projects on schedule.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is 3M 08367 paintable immediately after application?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: The surface becomes tack-free and paintable in about 30–45 minutes; full cure is around 24 hours.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Will this sealer crack or shrink over time?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: No—this moisture-curing urethane is formulated to be non-shrinking and remain flexible to resist cracking.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"3M","offers":[{"title":"Default Title","offer_id":48086192783518,"sku":"B00A9ZR8HO","price":49.92,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/3m-seam-sealer-08367-front-cartridge.jpg?v=1785889288","url":"https:\/\/northtrailauto.ca\/products\/3m-urethane-seam-sealer-08367-black-310-ml-cartridge-flexible-paintable-automotive-sealant","provider":"North Trail Auto","version":"1.0","type":"link"}