When you're working around tight spots in the field and the transmission starts weeping fluid, that little O-ring in the input housing is often the culprit. This essential seal keeps transmission fluid where it belongs—protecting internal gears and maintaining proper hydraulic pressure. When hydraulic filters get clogged or bypass, contaminated fluid starts circulating through your system, leading to sluggish operation, seal damage, and eventually complete hydraulic failure when you need your equipment most. This direct replacement O-ring gets your system sealed up right. What You're Getting Precision-sized 1/16" x 4" O-ring designed for transmission input housing sealing Quality rubber compound that resists transmission fluid breakdown and temperature extremes Exact factory specifications for proper fit and long-lasting performance Inexpensive fix that prevents expensive transmission repairs down the road Built for Real Farm Work The Massey Ferguson 300 series tractors were among the most successful agricultural machines of the 1980s and 1990s, dominating European farms with their exceptional power-to-weight ratio and reliability. These versatile tractors excelled in diverse farming operations including grain production, dairy farming, mixed agriculture, and specialty crop cultivation. The 362-375 models were perfect for medium-scale operations, while the powerful 390-399 series handled intensive cultivation, heavy plowing, and large-scale harvesting operations. This O-ring maintains critical sealing in the transmission input housing that keeps these workhorses running. Made to Last Each seal in this kit is specifically sized and made from fuel-resistant materials designed to handle the pressure and chemical exposure inside your transmission. The rubber compound stays flexible through temperature swings and resists the chemicals found in modern transmission fluids, giving you reliable sealing season after season. Good to Know Access to the input housing typically requires partial transmission disassembly, so it's worth replacing this seal whenever you're doing transmission work. Clean all mating surfaces thoroughly and inspect for wear that could cause future leaks. Any old gasket material or dirt guarantees a comeback leak. While you're in there, check the input shaft for wear and verify proper fluid levels after reassembly.