Use a Torch to Remove Control Arm Ball Joints

From the factory the parts are press fit. One part must have been heated and the other frozen before being pressed together. As the parts warm and cool, they become so tightly fitted together that a hydraulic press cannot press them back apart.

With the torch technique, cuts are first made so that the ball can be knocked out of place and then relief cuts are made in the bottom of the socket to relieve stress so it can be hammered out. With practice, this can be done without damaging the bore on the arm.
https://youtu.be/9RKHQHtjuTU

When did things change? I usually drive them out with an air chisel if a press is not available. Sometimes need a bit of gentle heat on the arm. I lube the new one before fitting as well.

He actually did lube it, I just didn't get that part on camera. I'm not sure when it got to the point where you couldn't push them out. He has a really cool 25 ton arbor press that I figured he would use but he said he has to cut the 4Runner ones out. I hadn't seen it done like this before so we worked together to film it.

Well if he does a lot of these and has trouble with a 25 ton press then only the gods know how they are put together. I can't see heat being used at the factory but maybe a big dead blow ram. Given that it is a bearing such a tight fit seems strange.

There is an inherent problem with this vid. IF the factory required that the ball joint be fitted THAT tight then his repair is substandard. It's not tight enough.
But then, the diameter of the arm hasn't changed substantially, and the new ball joint is (hopefully) factory standard size, then he shouldn't be able to press it in with what amounts to a G cramp.
I suspect that his 25 ton press is cactus delecti.

We actually did talk about that and it is a very good point. The new ones are definitely slightly smaller than the originals otherwise the arm would have needed to be expanded to get them in. The company making the new ball joints could have made them that way so these arms could be repaired. The new ones are press fit and are tight, they are just not as tight as the factory ones. So do they need to be as tight as the originals? It's hard to say. It is common to replace these like we did with ball joints that do press back in and in pretty much every other vehicle the originals can be pressed out fairly easily. They cannot physically come out of the arm because the large retaining clip on the bottom and the ball and socket itself is the weak point versus the socket and arm connection.

The factory parts are not larger for a tighter fit.

This bond is caused by rust. 150 years ago it was common practice in industry to chemically weld metal parts together by inducing a level of corrosion using a mild acid.

Drift keys were locked in place using this method in early steam powered machinery and water mills.

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Originally Posted by projectswithrich

We actually did talk about that and it is a very good point. The new ones are definitely slightly smaller than the originals otherwise the arm would have needed to be expanded to get them in. The company making the new ball joints could have made them that way so these arms could be repaired. The new ones are press fit and are tight, they are just not as tight as the factory ones. So do they need to be as tight as the originals? It's hard to say. It is common to replace these like we did with ball joints that do press back in and in pretty much every other vehicle the originals can be pressed out fairly easily. They cannot physically come out of the arm because the large retaining clip on the bottom and the ball and socket itself is the weak point versus the socket and arm connection.

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More than likely the entire arm is supposed to be replaced not refurbished. I'm old enough to remember when the ball joints on some vehicles were welded in.
A modern vehicle is a wonder of engineering in materials and build but are made to break. They, like all things made today have a designed finite work life.

Gotta watch using torches on those things. Stay clear everything. Cut the edge off and get the stud out quickly. I was cutting the rivets out of a control arm to remove the ball joint while I had the frame out replacing the transmission assembly. The heat transferred into the joint and it couldn’t expel the pressure fast enough resulting in a broken fusion weld and a boom so loud my ears still ring. The hot grease cup was propelled through my PPE and it imbedded itself in my eye socket. I now only have one eye, a crushed nasal cavity, and nerve damage. Be careful everyone.

Does the factory service manual sggest this method?

To be honest I never looked. I can’t imagine any factory manual suggesting torches because engineers live in a perfect world where everything is clean and rust free. I’m sure the factory instructions are to drill them out. I have drilled them out before and it’s a real pain. I’ll bet I had replaced 100 using the torch method and never had an issue. I think my accident was more of a fluke. I have started using my air hammer with a chisel and I toss a couple rags over it just in case part of the rivet wants to take flight. I discovered It’s a faster and cleaner method. Plus it saves my gas for other needs. It all really boils down to being careful and try to think of things that can go wrong before something happens. Hindsight is always 20/20, even with 1 eye. LOL.