How much ball joint play is acceptable / normal / safe?

[Dillon]

Happy Saturday to All,

Like all of us who have these cars, half a century old, mine could use a front end rebuild if not done already. My car has a 63kmi on the clock so it is probably not as bad as most originals its age but it is still 50 year old rubber wear components. I’ve been thinking next winter would be a good time to tackle that job I read is no day in the park.

Anyway, the car is slated to be in my daughter’s wedding to be held a few hundred miles away. Aside from detailing the car I did want to look it over to be assured it was ready for the trip and presentation. A tie rod end boot is torn so I’ll replace that. Everything else up front seemed solid ….until I got to the ball joints.

Checking the ball joints, I lifted the car from under the LCA and yanked the tire from all directions. All seemed tight. I wedged a pry bar under the tire, lifted, and the spindle separated upward from the LCA a good 1/8 inch….maybe slightly more. I checked all four ball joints and got about the same vertical, up and down, movement. But no horizon, side to side, movement at all.

I told a respected friend about this and he said”all ball joints need to be changed immediately”. He said there should be absolutely no noticeable up/down vertical movement in a ball joint at all. Unsafe. So I read a little bit and back in the day some ball joint up/down vertical movement is normal with some vehicles.

What do you think? Is this normal? Do at least the ball joints need to be replaced before the road trip and wedding? Father of the bride needs to arrive with the car on time and bride and groom need to safely drive away in the car.

Thanks so much in advance for your response.

 

[traintech55]

Well Dillon, one thing I have learned in 45 years of working on cars is you cannot predict when a part will fail. You could get the time you want out of it, or you could hit a pothole and it break right then and their.
My advice, don't take a chance on your family, or lovely car, get them fixed A.S.A.P.

 

[Newport 66]

NONE!

 

[CBODY67]

The test you describe used to be very common AND sold lots of lower ball joints in places they were NOT needed. When the tire is on the ground, all "play" in the joint is basically taken up, so "no play" per se when the car's weight is on the tire. There IS a spec for the dimension you saw, in the factory service manual. With lower ball joints, I'd personally be much more concerned with LATERAL "play" than vertical movement.

From my experience, unless you've driven on rough roads all of the car's 63K miles, with normal grease jobs every so often, the lower ball joints probably are in better condition than you might suspect. They don't normally deteriorate with age.

With an older vehicle, what deteriorates is the rubber bushings in the suspension, not the ball joints. The rubber pivot bushing in the lower control arm, where the torsion bar interfaces with that lower pivot can settle out with age and is not something that's normally visible as the upper control arm pivots are. Few know it's even there, but when it ages and settles-out, it can affect alignment, by observation.

The rear spring front and shakle bushings can also deteriorate and "sag", which can affect how the car drives, too. So that's something to look at, too. If the rear eye bushings don't "settle alike", it can effectively make the car "dog track" as the axle isn't square to the wheelbase. Many alignment machines have a "Set-back" measurement which is the amount the rear wheels aren't square with the front wheels.

There used top be a hand-held gauge to check lower ball joints with. Not sure if anybody has one any more. I know you're seeking to avert failure, which is great, so that's why you need to find that spec in the service manual and go from there.

On ALL of the Chryslers we've had, many with more than 100K on them, with normal maintenance, they've all got their original joints in them, some from when we bought them new. But in the '70s, it seemed that many alignment shops sold lbjs on most Chryslers that came in using the test you described. So, check the specs and go from there. Your money and peace of mind.

Just some thoughts,
CBODY67

 

[mrfury68]

When I got my Pennsylvania State Inspection License back in '84 there was a spec chart for all allowable play in ball joints. Chrysler Corp. vehicles had the most tolerance of any other manufacturer. The instructor even remarked how he had seen many Mopar ball joints needlessly replaced. We used a dial indicator to measure the movement and recorded the measurement. Working in a neighborhood service station (remember those) I got to work on all makes and models. Being the Mopar guy I was, I soon realized that Chrysler had a bigger, "beefier" ball joint and other suspension components than GM or Ford. When I rebuilt the suspension on my Fury about 10 years ago it had around 118K miles on the odometer. The ball joints and tie rods still would have passed a safety inspection. Being I was restoring the front end bushings and had accumulated the front end components over the period of a few years I replaced the ball joints, tie rods, etc. Along with a reman steering gear and new shocks the old Fury cruises so nice, especially on the open road.

 

[Davea Lux]

Mopar ball joints sit in a tapered socket inside the joint assembly. As the joint wears, it drops lower into the socket and the lateral play is compensated for. As long as the joint does not move laterally when you test it, it should be within specs and be nothing to worry about. As noted above, a lot of Mopar joints have up and down free play which is normal and a lot of fast buck artists will try to sell you new joints when you do not need them. The FSM gives specs on what level of up and down motion on the joints is acceptable

Dave

 

[mr. fix it]

here is what I found...

The first is for the 66 Polara/Monaco

The second is for the 73 Newport.

View attachment 180788

View attachment 180785

 

[CBODY67]

Thanks for posting!

 

[odcics2]

Back in 1972, I had a 68 Charger with 43,000 miles on it. Previous owner apparently didn't grease the ball joints enough! Had some slop and changed all 4 out.
Night and day difference in handling with fresh joints!!
So, maybe they weren't going to fail, but tightening up the front end REALLY helped...
Much more stable at 100 mph on the freeway!
Who doesn't like a solid feeling car?

 

[Davea Lux]

Back in 1972, I had a 68 Charger with 43,000 miles on it. Previous owner apparently didn't grease the ball joints enough! Had some slop and changed all 4 out.
Night and day difference in handling with fresh joints!!
So, maybe they weren't going to fail, but tightening up the front end REALLY helped...
Much more stable at 100 mph on the freeway!
Who doesn't like a solid feeling car?

One of the things that used to happen to a lot of front end components in the late sixties and early seventies was that Mopar sent their vehicles from the factory with "semi-permanent" front end lubrication and no grease fittings. Service personnel were
supposed to install fittings at 36k and re-grease the front end. As a practical matter, a lot of front end components failed because they did not have sufficient lubrication from the factory. A secondary issue was that a lot of gas station jockeys thought that since there were no fittings, they did not have to worry about greasing the front end. We used to install fittings on the high mileage fleet vehicles and police cruisers as part of the dealer prep. We found that this saved us a lot of warranty claims down the road.

Dave

 

[odcics2]

Good point. I remember changing plugs out and installing all 8 fittings, back in the day, but I have had so many MoPars, I'm not sure which ones they were!

 

[garyh]

If your going to Replace all your bushings, why not replace the Ball Joints They are Very Available. Your going to have the control arms off for the bushings anyway . Try to get New ball joints Made in USA. Look on Ebay for NORS.