A Transfer Case is a fundamental part of the 4-wheel drive system on your 2001-2004 GM 2500HD/3500HD. Bolted to the back of the transmission, a transfer case has two driveshafts connected to it that run to each axle. It is responsible for transferring power to the front wheels and rear wheels in 4-wheel drive systems. 4-wheel high will maintain the same gear ratio as 2-wheel drive and is for high-speed situations such as driving on dirt or snow-covered roads. Contained inside the transfer case is a set of gears and chains that are engaged or disengaged depending on the drive mode selected. 4-wheel low is for low-speed situations where maximum torque is required such as driving up a steep rocky hill or pulling out a stuck vehicle.
The Transfer Case is designed to be used in off-road or low-traction situations and is not recommended to be used on dry pavement where wheel slip is not possible. Wheel slip is possible in loose terrain, alleviating any binding that can occur on dry pavement. Since transfer cases lock the front and rear axle together, the wheels are unable to spin at different speeds making turning and cornering on dry pavement difficult. Shop XDP's large selection of Transfer Case products from the top brands such as Merchant Automotive, PPE, Sun Coast Converters, and Dorman. Transfer Cases generally are very strong from the factory and do not require internal upgrade unless the vehicle is used for extreme off-roading or racing. External upgrades such as transfer case braces are offered for certain applications that add structural rigidity to prevent damage from high torque loads and twisting.
