Ball joint discussion
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Elder User
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From: Seattle
Ball joint discussion
I guess if this is in the wrong spot you'll all move me but here goes....
Can someone describe the purpose of the ball joints on a vehicle. My Ranger has upper and lower ball joints, occasionally they need replacement.
1) Why do they need replacement? What is the ball joint doing?
2) What are you replacing? It seems like it would be the end piece of the tie rod or similar item - not some small object you could replace without replacing the whole assembly.
3) Some ball joints have grease fittings, why are those better, longer lasting?
My overall impression of the ball joint is the end-piece of the tie-rod. I don't see how you can "replace" the joint without replacing the whole thing, without replacing the whole tie rod in effect.
Can someone describe the purpose of the ball joints on a vehicle. My Ranger has upper and lower ball joints, occasionally they need replacement.
1) Why do they need replacement? What is the ball joint doing?
2) What are you replacing? It seems like it would be the end piece of the tie rod or similar item - not some small object you could replace without replacing the whole assembly.
3) Some ball joints have grease fittings, why are those better, longer lasting?
My overall impression of the ball joint is the end-piece of the tie-rod. I don't see how you can "replace" the joint without replacing the whole thing, without replacing the whole tie rod in effect.
Elder User
Joined: Sep 2006
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From: Alma Arkansas
A ball joint on a "A arm" type suspension does bacically the same thing your hip joint does it goes up down AND rotates as well. Ball joints and tie rod ends are completely diffrent parts.
You usually have two ball joints located at each end of the controll arms, They in turn hold the Spindle, brake ,wheel in place while allowing the suspension to move up and down and the wheels to steer.
The reason ball joints wear is the entire weight of the front of the vehicle is supported by the two lower ball joints. Although now days the factory ball joints "should" last pracitaclly the entire life of the vehicle.
The factory sealed type ball joints are probably better than any aftermarket "greaseable" type provided they stay sealed.
You usually have two ball joints located at each end of the controll arms, They in turn hold the Spindle, brake ,wheel in place while allowing the suspension to move up and down and the wheels to steer.
The reason ball joints wear is the entire weight of the front of the vehicle is supported by the two lower ball joints. Although now days the factory ball joints "should" last pracitaclly the entire life of the vehicle.
The factory sealed type ball joints are probably better than any aftermarket "greaseable" type provided they stay sealed.
Senior User
Joined: Aug 2006
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From: St. Paul, MN
A ball joint is just like the name implies. It's a ball that fits into a socket that allow 360* of rotation. A tie rod does have a ball type joint on the end, when it goes bad you replace the whole tie rod. The ball joints which you refer to connect the steering knuckle to the control arm. They are the joints that allow the wheel to turn. It's the same type of joint as on the end of a tie rod. They go bad becaue every time your wheels turn your ball joints turn. Inside the joint is a metal ball surrounded by a metal "bearing" with a thin layer of grease in between. As they age the grease gets displaced and you've got metal rubbing on metal everytime the wheels turn. Once metal wears away you've got "play" in the joint because it's no longer a tight fit around the ball.
The reason some don't have grease fittings is that the manufacturer feels it creates a sealed design in which grease can never leak out. Over time the rubber boots crack and deteriorate and grease leaks out. Most quality aftermarket brands like Moog or Spicer put grease fittings on just about all of there ball joints.
The reason some don't have grease fittings is that the manufacturer feels it creates a sealed design in which grease can never leak out. Over time the rubber boots crack and deteriorate and grease leaks out. Most quality aftermarket brands like Moog or Spicer put grease fittings on just about all of there ball joints.
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From: Seattle
I took a look at some, although not mine it particular. So basically the ball joint is more of an insert that goes in the control arm that the spindle rides on.
So things like ball joint presses are used to push the insert out of the control arm. Now it's making sense, the pickle fork is used to lift the control arm off the spindle - which is inevitably practically welded to it from all those miles and bumps.
So things like ball joint presses are used to push the insert out of the control arm. Now it's making sense, the pickle fork is used to lift the control arm off the spindle - which is inevitably practically welded to it from all those miles and bumps.
Elder User
Joined: Sep 2006
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From: Alma Arkansas
Originally Posted by eigenvector
I took a look at some, although not mine it particular. So basically the ball joint is more of an insert that goes in the control arm that the spindle rides on.
So things like ball joint presses are used to push the insert out of the control arm. Now it's making sense, the pickle fork is used to lift the control arm off the spindle - which is inevitably practically welded to it from all those miles and bumps.
So things like ball joint presses are used to push the insert out of the control arm. Now it's making sense, the pickle fork is used to lift the control arm off the spindle - which is inevitably practically welded to it from all those miles and bumps.
Posting Legend
Joined: Sep 2001
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The greasable ball joints are not immune to wear either. Often dirt gets pumped into the joint along with the grease which wears the joint. The boots also crack and fail allowing water and dirt to enter the joint.
