Hughes Performance has your high horsepower 4L80E solution! Our new Extreme Duty 4L80E/4L85E input shaft is rated for use with 1,500+ flywheel horsepower, and comes standard in every one of our Heavy Duty (HD) series and Extreme Duty (XD) series 4L80E transmissions. This superior new input shaft is available under part number HP2514. This premium shaft is manufactured from a billet of 300M steel. As part of the manufacturing process each HP2514 input shaft is subjected to a multi-stage heat treatment process and then finished with a unique nitriding treatment which gives the shaft its distinctive black appearance.