Is this a bad u-joint?

Khill0111

New Member
Original poster
Joined
Dec 20, 2019
Messages
10
Location
Jackson Ga
I have what sounds like may be a bad u joint, at about 10 to 30 miles an hour what sounds like griding metal begins and it is only while moving, suspect bad u joint but no vibration and need another opinion
 
A ujoint normally sounds off when either a direction change (forward and back) or during shifting when the momentum changes (again forward and back). Most obvious when starting to move from a stop. Once under load they are held in position by the torque on the d.s. If it is making that kind of noise it is ready to let go. Slide underneath and give the d.s. a few twists back and forth. There should be NO movement at the Ujoints.
 
You have ujoints in your driveshafts, and in your front axle shafts.

If there is any rotational play, I'd consider it worn enough to replace it.

What you're describing though, sounds more like a wheel bearing to me. Ujoints generally sound pulse like.

Jack up the front end and support it by the axle. Spin the tire and look for play in the ujoint inside the knuckle right behind the brakes. If there's play it's bad. Then, looking towards the wheel from the side of the Jeep, grab the tire and try to tip it up and down. If it wiggles, it's probably your wheel bearing. Could be a ball joint, but the sound your describing would lead me to believe otherwise.