Seems like I just posted an article about this…Hum, that’s right! I just did one about CV axles! CV joints in your drive axles and u-joints on your drive shaft perform pretty much the same function in that they allow a change in the angle of the shaft while still letting it transfer the torque from your transmission to your drive wheels. The symptoms of u-joint failure are very much like CV joint failure.
When U joints begin to wear, one of the first signs you’ll notice is vibration. A joint that has developed excess play can rattle at slow speeds and vibrate at highway speeds. The vibration at first might be slight and difficult to pinpoint, but it will become worse, usually within a few hundred miles.
If you suspect your U joint might be going bad, find an empty parking lot and turn the wheel all the way to the right or the left and slowly drive in a circle. Most of the time, if your U joint has worn to the point of being loose you’ll be able to hear a clicking noise with each rotation of the drive shaft. I should tell you that you’ll probably only hear the noise if the car is in gear and under a little bit of power. If you have a manual transmission, don’t push the clutch in because you won’t hear the noise.
If you have a way to jack up your car and put it on stands you can visually inspect your drive shaft. With your car safely on stands and in neutral with the parking brake off, slide under your car on your back and twist the drive shaft one way then back while watching the U joints. They should rotate with the drive shaft with no play or sloppiness.
If you are unsure about the condition of your U joints, bring your car in for inspection. If a worn U joint catastrophically fails at highway speeds, the drive shaft can rotate violently out of control and cause major damage to the under body of your vehicle. If the front U joint snaps, the one directly behind the transmission, it is possible for the drive shaft to penetrate the roadway or into a pot hole and flip your car end over end as proven in the television show called “Myth Busters.” That’s not the way you want to wind up in a You Tube video. If you suspect your U joints are going bad, play it safe and have them inspected right away.
If you have any questions, please don’t hesitate to call Your Local Mechanic, All Tune and Lube Total Car Care. Complete Auto Repair and Maintenance