A universal joint, U joint, is a joint in a rigid rod that allows the rod to 'bend' in any direction, and is commonly used in shafts that transmit rotary motion. U joints are a vital link in your vehicle's driveline. If these joints fail, you could be left stranded. Fortunately this can be prevented through periodic maintenance and/or replacement. A bad U-joint can most commonly be detected by a metallic clunking sound when the vehicle is placed in gear. This indicates play in the U-joint and should be investigated as soon as possible. Other symptoms of a failing U-joint are vibrations from the drive shaft, noticeable especially between 25 and 35 mph; shudder on acceleration and/or squeaking noises. If you experience any of these symptoms A plus transmission can help. You do need an appointment for this service. We can replace U-joints in your vehicle while you Waite.
U-joints are usually found at either end of a driveshaft. Their purpose is to transfer engine power and torque from the transmission to the differential and drive wheels as the suspension travels. As the driveshaft spins it has to do so as the suspension moves up and down. The universal joint allows the driveshaft to put a positive spin on engine power and handle the twist of torque regardless of whether the road is smooth, or rough.
All that spinning under power eventually causes even the toughest u-joint to wear out. The heart of a u-joint is an of x-shaped cross. The cross spins around in the driveshaft yoke thanks to four caps that sit on top of the tips of the cross. Inside each of these caps are tiny needle bearings and high temperature grease. Through the miracle of gravity and centrifugal force, the grease travels from inside the cross as the u-joint spins, and keeps these needle bearings happy and alive as they spin along.
Over time the grease can spin out permanently. Wear can set in, causing the needle bearings to eat into the hardened steel of the cross. Symptoms of worn u-joints include clunking when you put the vehicle in gear, or vibration that matches transmission output speeds. At best, a worn u-joint causes vibration and clunky operation. At worst, a suddenly broken u-joint can cause an accident.