The driveshaft is a long tube or two separate tubes. Main points connect to the transmission at one end and the differential at the other. Universal joints stand like hinges in the center on both one-piece and two-piece driveshafts. Single-piece rear driveshafts connect with a cup-shaped fitting at the front that slides into a rear housing when the car works. In contrast, two-piece rear driveshafts link two parts together using a cylindrical yoke that unlocks the pieces as the car moves. Two-piece drive shafts forTerrain vehicles have a support bearing linking to the frame crossmember, while the 4WD front driveshaft uses a slip joint to allow changing its length. The driveshaft needs little attention, since its universal joints come pre-lubricated and don't wear out, but if problems show up, you may need to remove it from the car. We need to keep the driveshaft clean and check it for damage. Also, make sure any balancing weights are okay, and install the driveshaft back exactly as it was for the correct balance. When your car shakes or makes noises when driving, you should take it on a check drive to figure out which part needs fixing. To do the check, lift the vehicle and block the wheels so it can't move. Make sure you look at the driveshaft for dents and cracks; if you see oil leaking from either end, the seal needs replacement. When inspecting the vehicle, an assistant needs to do two checks. They rotate a wheel to check how well the universal joints work, and they look for wear or damage at the center bearing. When parked still, you can test the universal joint by trying to turn its shaft. Any movement shows it's wearing out. Four-wheel-drive owners should check the front driveshaft bolt tightness, and search for leaking fluid from the slip yoke, transfer case, and front differential connections. This reveals worn out seals in the front drive. Before moving on, check both front driveaxle joints for movement and look for any fluid dripping out from the rubber axle boots or ends. If axles leak around their flanges, the oil seal is likely broken.