If you've ever gotten stuck in your 2017-2019 GM 2500HD/3500HD and needed 4-wheel drive, then a transfer case is what helped get you out. There are usually two different gear ratio options with a Transfer Case, 4-wheel low and 4-wheel high. 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. The Transfer Case mounts to the back of the transmission and is what the front and rear drive shafts connect to. It is responsible for transferring power to the front wheels and rear wheels in 4-wheel drive systems. 4-wheel high is used in high-speed settings such as dirt or snow, whereas 4-wheel low is used in low-speed settings like steep rocky hills where maximum wheel torque is required.
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. Shop XDP's large selection of Transfer Case products from the top brands such as Merchant Automotive, PPE, Sun Coast Converters, and Dorman. A Transfer Case typically does not require internal upgrades or modification unless the vehicle will be used for extreme off-roading or racing applications. In some applications an external brace can be added to increase the structural rigidity of the transfer case to prevent damage from high torque loads or twisting. When you shift the Transfer Case into 4-wheel drive, it locks the front and rear axles together so that they spin at the same speed.
