How does transfer case work

Odd sounds are one of your car's ways of letting you know something might be wrong. It may be a minor problem like a… Read More. JavaScript is Disabled For the best experience and to ensure full functionality of this site, please enable JavaScript in your browser. Schedule Appointment. Search for:. Enter Email Confirm Email. This field is for validation purposes and should be left unchanged. Skip to content. Find a Location Locations.

Make An Appointment Appointments. What Is a Differential? What Is A Transfer Case? What Is the Purpose of a Transfer Case? Symptoms of Trouble in the Differential Front and rear differential problem symptoms can vary and need to be inspected by a technician immediately. A howl or whine during acceleration over high or low speeds. Rumbling or whirring at speeds over 20 miles per hour, but changes while turning.

Frequent clunking sound every few feet or when starting to move. Vibration that increases with speed. Transfer cases usually use ATF, but check with the manufacturer's specifications before servicing the fluid. A vacuum controlled unit requires a specified vacuum from the engine "Hg. If low vacuum is found at the case, check all the lines and reservoirs for cracks and wear.

They're also controlled manually, hydraulically, or electrically. Manual control is typically a shifter found on the floor of the vehicle. A transfer case is the center of the drivetrain of four-wheel drive and some all-wheel drive vehicles.

Mounted to the back of the transmission, it splits engine power and sends it to the front and rear axles by means of front and rear drive shafts. It also synchronizes the difference in rotation of the front and rear wheels, and may contain one or more sets of low range gears for off-road use.

Low range gears in the transfer case allow the vehicle to drive at much slower speeds while still operating within the usable power band or RPM range of the engine. This also increases the torque available at the axles. Low-range gears are used during slow-speed or extreme off-road maneuvers, such as navigating dangerous roads, rock crawling, or when pulling a heavy load. This feature is often not present on all-wheel drive vehicles.

On some vehicles, such as four-wheel drive trucks or vehicles intended for off-road use, the transfer case is controlled by the driver. The driver can engage the transfer case into either two-wheel drive or four-wheel drive mode. This is sometimes accomplished by means of a shifter, similar to that in a manual transmission. On some vehicles, the transfer case may be electronically operated by a switch or button.

Others have transfer cases that are not selectable and are permanently locked into all-wheel drive mode.