Bad ball joint?

[IndyIan]

Can a bad ball joint feel and look perfectly good off the car? The boot wasn't torn and I couldn't feel any looseness by hand at all. Also it swivelled smoothly through the whole range of motion.
Does the rubber boot pull the ball tight into the socket enough that you couldn't feel play by hand?
I have a bad feeling my regular shop decided it was time to make some real money off me, and they said it needed both sides done. Normally I don't ask to see the parts, but I decided too on this one. Both joints seemed like new to me but I didn't shake the wheel while it was on the lift, and the mechanic said they were loose when they did that. My [censored] meter was reading high when he said that.

 

[Trav]

If its worn out you will know it. No looseness or play in any direction especially up and down and smooth operation is a sign of a good joint.
New joints are only very tight for the first few thousand miles then they break in and feel as you describe.

The boot does not pull it tight enough that you couldn't feel the play. Follow the manufacturers spec if there is one published for the serviceable amount of play allowed.
IIRC Ford had 1/32 allowed and some stations were failing the trucks during inspection anyway, there was a service bulletin a few years ago about this.

 

[Gabe]

I don't think you can tell if a modern ball joints are bad simply by wiggling it with your hand. There has to be a load on the ball joint to correctly check it.

You could take a look at your tires. A bad ball joint(among other things) will normally cause uneven tire wear.

 

[RF Overlord]

Upper or lower?

You don't test lower balljoints by shaking the wheel. The traditional way to check is to jack up the wheel by the lower control arm, then put a pry bar under the tire and pry up. You should feel no play and have no clicks or clunks.

Look at it this way...whether they were bad or not, you should never have to do balljoints on that car again...

 

[eljefino]

What car is this? A lower ball joint where the spring is on the lower control arm is tested by the pry method RF overload describes. An unloaded lower... on a macpherson strut, etc, gets tested with the tire shake and maybe prying between the LCA and knuckle.

Sometimes they recommend doing both at the same time just to save money on alignment, keep you from coming back in 5000 miles, etc. But they should be clear on needs vs wants.

 

[IndyIan]

It was the lower joints on the Tracker, it has mac struts up front.
Now that I think about it though, its got the springs between the control arm and the frame so the ball joints actually transfer the whole weight of the vehicle to the hub.
So normally they have like 800lbs of tension on them, and probably a couple hundred even when its on the lift, so maybe thats a factor for a hand test off the vehicle?
The shop owner is a mechanic, but wasn't there on Friday afternoon, so I'll stop in and have a chat with him on Monday. Maybe his techs were getting "creative" in his absence...

Also the whole control arm needs to be changed to get new ball joints, so it was $480 just for the parts... On the phone he said both needed to be done, so initially I didn't even question it.

 

[RF Overlord]

Originally Posted By: eljefino
An unloaded lower... on a macpherson strut, etc, gets tested with the tire shake and maybe prying between the LCA and knuckle.
Thanks for clarifying that...

 

[Trav]

Originally Posted By: Gabe
I don't think you can tell if a modern ball joints are bad simply by wiggling it with your hand. There has to be a load on the ball joint to correctly check it.

You could take a look at your tires. A bad ball joint(among other things) will normally cause uneven tire wear.


Once its out of the vehicle the loaded/unloaded methods of testing are a moot point.
you can certainly determine it condition by hand off the car.

Loaded joints can sometimes appear to be okay because you need to overcome the load of the spring/torsion bar to feel the play but again this is only applicable when its mounted in the vehicle.

 

[IndyIan]

Originally Posted By: Trav
Originally Posted By: Gabe
I don't think you can tell if a modern ball joints are bad simply by wiggling it with your hand. There has to be a load on the ball joint to correctly check it.

You could take a look at your tires. A bad ball joint(among other things) will normally cause uneven tire wear.


Once its out of the vehicle the loaded/unloaded methods of testing are a moot point.
you can certainly determine it condition by hand off the car.

Loaded joints can sometimes appear to be okay because you need to overcome the load of the spring/torsion bar to feel the play but again this is only applicable when its mounted in the vehicle.

Thanks for your help, it will be an interesting visit to the garage on Monday. I bet the control arms have disappeared over the weekend, stupid me didn't take them.

 

[Pavlov]

My Diamante workshop manual tells me the only accurate test is to disconnect the ball joint, put the nut back on, and use a torque wrench to see what force is needed to get the shaft turning in the body of the joint. Replaced some that were below spec, and it cured a steering wobble and wander.

 

[Trav]

Originally Posted By: Pavlov
My Diamante workshop manual tells me the only accurate test is to disconnect the ball joint, put the nut back on, and use a torque wrench to see what force is needed to get the shaft turning in the body of the joint. Replaced some that were below spec, and it cured a steering wobble and wander.


It may be the only accurate way to determine it on that vehicle but it certainly does not apply to all vehicles or all joints.
The amount of inch pound needed would be very low and could easily be skewed by the grease being used (in a greasable joint) or even what temperature you were doing the test at.

It sound like they are just looking to measure resistance but that would fail almost every Ford pick up (and a few others) sold in the last 30 years which allowed up to 1/32 play.
Some greaesable type joints have a wear indicator, the grease nipple flange will recede into the housing as wear increases.

Like i said earlier the only way to really tell unless its obviously screwed is to follow the manufacturers spec if they publish it.

 

[IndyIan]

Originally Posted By: Trav

Like i said earlier the only way to really tell unless its obviously screwed is to follow the manufacturers spec if they publish it.

I found the Suzuki service manual online. The test they have to detect a bad ball joint is:
With the joint unattached to the the hub, look for torn boots, move the joint through out its range. If its smooth its good, if its grindy, its not.
So by that criteria both were still good.
The Tracker does drive alot better, but they also replaced the LF wheel bearing which had been noisy for quite a while, and did an alignment, along with replacing the front sway bar bushings. So those fixes might have been all the improvement.

 

[Trav]

Quote:
The Tracker does drive alot better, but they also replaced the LF wheel bearing which had been noisy for quite a while, and did an alignment, along with replacing the front sway bar bushings. So those fixes might have been all the improvement.

Changing those parts would make a big improvement. I wonder how you check for ball joint wear by prying up and down on the wheel when the wheel bearing is shot?

 

[951Indy]

What Trav said. Odds are the bearing replacement took care of any play they detected, but "while we're in here....".

On the plus side, you know the ball joints and control arm bushings are new.