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Discussion Starter #1
Probably due to a shoddy repair job on my front shocks (should've done it myself!), the bottom bolt of one front shock came loose. Scraped the heck out a front wheel.

Long story short, I have a damaged lower front control arm.
I can get one from a junkyard for $120.

What would it take to swap out the old control arm?

- do I need to remove the lower ball joint? I've read that that's a difficult task in itself.

- the other two corners of the control arm look simple to deal with, am I right?

I guess it comes down to whether the tools I need will cost more than the cost to outsource the job. Opinions?

Thanks!
 

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What is the damage to the lower control arm? If it is just scraped, you shouldn't consider that damage. It takes quite a bit to damage that lower arm to make it unusable.
 

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Discussion Starter #3
Hello 43sqd

I didn't want to bore everybody with the gory details, but since you asked. :)
After the shock came loose, it was left dangling from the upper mount. Every time I made a right-turn, the shock would grind against the inside of the wheel. At first I thought it was the steering box going out again (replaced about 6 years ago).

Bolted the shock back into place, but the lower bolt was very hard to turn and stopped at about 98% in. Few days ago, the lower shock mounting bolt snapped off in the control arm.

I've tried penetrating oil, easy-out's, heat, even left-hand drill bits, trying to get the damn bolt out. No luck.

An ML is too heavy to drive around on only 3 shock absorbers. :->
 

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It's unfortunate that this happened, but anytime a bolt is difficult to tighten, the bore hole must be re-tapped. Here are the directions for R&I of the lower arm.

Also make sure you get the proper bolt and washer for the shock mounting from the dealer.
 

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Just one quick safety comment. Torsion bar (spring) is under extreme tension. It holds entire weight (1/2) of vehicle. Make sure both front wheels are off the ground.
 

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Discussion Starter #6
Thanks a bunch guys!

Especially you, 43sqd. :)
The PDF's are a huge help.

Just one more question...

In your experience, do you think it's really necessary to Remove the Steering Knuckle to Remove the lower control arm?
The control arm attaches to the steering knuckle by just one ball-joint.

The removal process for the control arm looks pretty straightforward.
But pulling the steering knuckle seems much more involved and requires more special tools than the control arm alone.

I'd really like to do this myself, if at all possible!

Thanks again,
Bill
 

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I have done the control arm without removing the knuckle so I don't see a problem there.

Once this is all done I do suggest an alignment. After all that money on parts and with
the cost of good tires it is good insurance to make sure all four corners are within spec.
 

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Discussion Starter #8
Thanks Noodles! Both for the reply and the good news.

Crawled under the car last night. It does look possible, with the right tool of course, to press out the "lower supporting" ball joint from the steering knuckle.
Now to buy the control arm, special socket for screwing in the new ball joint, and a ball joint press.

Probably going to scrape a few knuckles, but I'm looking forward to it.

Needs an alignment anyway, I'll add it to the list.
Rear main oil seal is next after this repair.

Note to self: Take pictures, give back to the forum.
 

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The giant special socket is a 3/4" drive so you will need a 3/4" to 1/2" adapter unless
you have a 3/4" drive setup already.
 

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The reply I gave about doing it without taking the knuckle off may not have been good advice. The simple reason is safety and I take for granted that I have access to a lift and all the tools. I was not looking at the big picture in your case.
I would be concerned that if it is not done on a lift with all the correct tools that the PDFs 43sqd posted should be followed. The risk of serious injury is present if this going to be a DIY on the ground with jack stands. With the knuckle off it keeps it a lot safer. On a lift the vehicle is more secure and you have much more room to work parts the require high torque values. Also the angle you can approach the parts from makes it much easier and safer.
I am sorry for the confusion I may have caused.

Thanks a bunch guys!

Especially you, 43sqd. :)
The PDF's are a huge help.

Just one more question...

In your experience, do you think it's really necessary to Remove the Steering Knuckle to Remove the lower control arm?
The control arm attaches to the steering knuckle by just one ball-joint.

The removal process for the control arm looks pretty straightforward.
But pulling the steering knuckle seems much more involved and requires more special tools than the control arm alone.

I'd really like to do this myself, if at all possible!

Thanks again,
Bill
 
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