How much vertical movement in a ball joint is too much

cliffish

TJ Expert
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Joined
Oct 22, 2017
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5,317
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St James, NY, United States
I am using a pipe under the tire lifting up to see if the ball joint is bad, how much up/down movement is too much? the DS moves a little bit enough to hear it click. I can try and post up a video unless the answer is no movement is acceptable. Also would you do both sides at the same time?
 
Ball joint or U-Joint? Either way. Any play is to much.
You're going to be replacing a lot of ball joints then. I find that generally a new set will develop a small amount 1/16" or less vertical play in a surprisingly short number of miles. Any lateral play in any direction is bad for the upper. Vertical play of a small amount has to be acceptable or we will be swapping ball joints every 10 thousand miles or so.
 
I am trying to test this by myself, so I was using the pipe from the front to lift. I read a post from Blaine on another forum and the trick is to see any lateral play on the top ball joint, so I need to put the pipe from the side to tilt in the top of the tire. I don't think I can get the wife in the 28 deg. garage at almost 11 pm to play with a video now.
 
I'd sure like to find any reference from the factory to verify what we see. It would make this so much easier.
I was told this by the dealer back when my ‘96 XJ was only a couple of years old and I took it in to have the BJ’s replaced under warranty. He put a dial indicator on it and showed me it had .024 play and was well within the .060 allowance.
I assume there’s no reference in the FSM about it? I don’t have one to check.
 
I was told this by the dealer back when my ‘96 XJ was only a couple of years old and I took it in to have the BJ’s replaced under warranty. He put a dial indicator on it and showed me it had .024 play and was well within the .060 allowance.
I assume there’s no reference in the FSM about it? I don’t have one to check.
I've asked everyone I know connected with the dealer, dealer parts, dealer mechanics and none have offered up any documentation to verify. I know from working on ambulances that some vertical is in spec. We replaced all of the ball joints in the fleet before the yearly DOT inspection. The inspectors promptly failed all of them due to the new Ford OEM parts having a small amount of vertical play. The owner had to get a letter from Ford Corporate and submit it to the DOT inspectors to get them passed. It is hard for me to imagine that Jeep ball joints would be much different especially when we see the same thing after a few miles. I've also queried companies that manufacture and supply them what the allowable tolerance is and have yet to get an answer.
 
I replaced mine when I discovered 1/8" of vertical play on the driver side bj's. Passenger side was still tight. After 167K miles and most of those miles on larger than stock tires, I don't think the factory Spicers owed me anything.
 
Mine probably have the originals with a 104500 on the clock. Basically zero movement on p/s, but enough to hear a click on the d/s. I do hear a popping sound on slow acceleration that I am chasing down.
 
Mine probably have the originals with a 104500 on the clock. Basically zero movement on p/s, but enough to hear a click on the d/s. I do hear a popping sound on slow acceleration that I am chasing down.
Generally, the weight of the front end holds the lower ball on top of the lower pin in the socket. It would be very difficult to get that to click without removing all the weight off the axle. This is a lower, upside down.
83753
 
Generally, the weight of the front end holds the lower ball on top of the lower pin in the socket. It would be very difficult to get that to click without removing all the weight off the axle. This is a lower, upside down.
View attachment 83753
I am not itching to do this job or buy the BJ press and associated adapters, just going to make sure it at least close to spec. I will try again this eve with a helper (wife) while I have the TJ on the lift and in the garage.
 
I am not itching to do this job or buy the BJ press and associated adapters, just going to make sure it at least close to spec. I will try again this eve with a helper (wife) while I have the TJ on the lift and in the garage.

You can rent lots of these tools that you may not use frequently. I did my ball joints and front U joints right after I got the jeep. It was a learning experience I dont hope to do again.
 
You can rent lots of these tools that you may not use frequently. I did my ball joints and front U joints right after I got the jeep. It was a learning experience I dont hope to do again.
🤣
Welded a truss for the mid arm and some other stuff on a front axle a couple days ago. Didn't feel like holding wet rags on the upper balljoint to not melt the race in it. Whipped out the ball joint press and popped the uppers out in about 5 minutes for both sides. All about perspective. ;) While that was drying, we assembled the u-joints in a set of Revolutions.
 
🤣
Welded a truss for the mid arm and some other stuff on a front axle a couple days ago. Didn't feel like holding wet rags on the upper balljoint to not melt the race in it. Whipped out the ball joint press and popped the uppers out in about 5 minutes for both sides. All about perspective. ;) While that was drying, we assembled the u-joints in a set of Revolutions.
Yeah but you have probably done it more than once, which is what my count is up to now lol
 
Yeah but you have probably done it more than once, which is what my count is up to now lol
Thus the "all about perspective" part. Way more than once, 100's of times. That and I've modified the various cups that come with the kits to be easier to use since I use the press upside down from the way it is designed to be used.
 
Did the pipe lift from the sides, zero lateral movement on top ball joint, calling this done. It would have turned into a "while I am in there weekend" and I would have kept moving into the diff replacing everything. Too many other projects on the TJ, Corvette and getting my TR6 ready for sale.