{"product_id":"th400-heavy-duty-forward-drum-300m-input-shaft","title":"TH400 Extreme Duty Forward Drum \u0026 300M Input Shaft 35-Spline","description":"\u003ctable id=\"II\"\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand:\u003c\/td\u003e\n\u003ctd\u003eSpeedmaster\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Number:\u003c\/td\u003e\n\u003ctd\u003ePCE623.1028.01\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Type:\u003c\/td\u003e\n\u003ctd\u003eAutomatic Transmission Drum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Drum Material:\u003c\/td\u003e\n\u003ctd\u003eHigh-strength chromoly steel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSprag Assembly Included:\u003c\/td\u003e\n\u003ctd\u003eNo\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eQuantity:\u003c\/td\u003e\n\u003ctd\u003eSold as a kit.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003eTake your GM TH400 transmission to the next level with this premium heavy duty forward drum and 300M input shaft combo. Engineered for high-power street, strip, or off-road use, this kit addresses the critical failure points of stock components with a focus on strength, precision, and reduced rotating mass. Heavy Duty Forward DrumConstructed from high-strength chromoly steel – providing exceptional durability without the weaknesses of cast iron or aluminum. Lightweight design – 3 lbs lighter than stock and nearly the same weight as an aluminum drum, without compromising strength. Oversized 28-tooth shaft-to-drum spline – significantly stronger than the factory design, addressing a common failure point. Enhanced clutch engagement – features dual clutch splines (28 vs. 14) for better support of clutch separators. Precision-machined lightening holes – reduce rotating mass and align with input speed sensors in aftermarket cases. Optimized design – includes ribbing and internal diameter reduction at the middle seal area for further weight savings. High-RPM checkball capsule included – prevents pressure drop at 5500+ RPM for consistent clutch performance. No middle seal required – compatible with clutch volume spacer kits if fill\/drain time needs adjustment.   300M Extreme Duty Input Shaft Made from ultra-tough 300M steel – heat-treated for exceptional resistance to twist and fracture under extreme torque. 1-1\/8\" diameter, 35-spline design – the strongest configuration that fits within a stock-style stator tube. 35% stronger than standard 1\" shafts – built for serious racing and high-horsepower abuse. Compatible with aftermarket drums using 28-tooth internal spline – ensures secure engagement with heavy duty drum.   Installation Notes: Input shaft requires a 35-spline turbine hub in the torque converter. Must be used with a large-diameter stator support tube.","brand":"Speedmaster","offers":[{"title":"Default Title","offer_id":44903269662885,"sku":"PCE623.1028.01","price":1250.0,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0582\/7896\/9509\/files\/PCE623.1028.01.png?v=1778350479","url":"https:\/\/musclecarhq.com.au\/products\/th400-heavy-duty-forward-drum-300m-input-shaft","provider":"Muscle Car HQ","version":"1.0","type":"link"}