What part is this?

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I noticed a torn boot that connects the UCA to the birf. It's leaking grease. What is this part called and how easy is this to fix?
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You don't have birf's on 100's, those are front axle hubs. The other component in the picture is the upper control arm (UCA). I think that is simply called the UCA joint, but I could be wrong. I know there was a thread recently about changing the exact same joint but on the lower control arm. I'm pretty sure the upper is the same story. They got the parts from Napa and it wasn't bad, around $70/each.
 
That would be an upper ball joint....no OEM replacement for the actual joint without purchasing the whole arm...but you can just get those dust covers...about $12 each and not really difficult to replace.
 
Do you have to unbolt the knuckle to replace the boot? If it's easy, it may be a good time to simply replace regardless of torn or not. I'd rather do some PO to prevent dirt and water from getting in there than wait for it to tear.
 
Ok, thanks. I will place a call to CDan and replace both. How easy is it to replace? Easy for you Chris does not mean easy for me..
 
Craig, I have a couple of the boot rebuild kits in the garage. I don't need them and you can have them if you want. Just come get them.
 
Ok, thanks. I will place a call to CDan and replace both. How easy is it to replace? Easy for you Chris does not mean easy for me..

Took me over 10 hours to do a body lift on my truck.....NOTHING goes easy for me....especially since my truck resided in Illinois early in its life...rusty bolts suck.

you can do this though....maybe need a ball joint removal tool to get that apart...but your truck is clean so it should go well for you.
 
Mxndrnks said:
Craig, I have a couple of the boot rebuild kits in the garage. I don't need them and you can have them if you want. Just come get them.

Thanks Jonathan, I may take you up on your offer if I decide to tackle this myself.
 
While you're in there, you might want to bend that cotter pin out of the way so the point isn't pointing at your tire. If you air down enough and get that tire flexed out, it might be able to reach your inside sidewall.

That first pic is blurry, but it looks like that is what I'm seeing.
 
Very easy to replace, I just did mine. Here's a couple of key points that should help. Securely support the axle assembly before you separate the UBJ and partially install the retaining wire before you install the boot. You may want to separate the brake line and the abs sensor from the arm to minimize the chance of damage. Here's the puller I used. Good luck!
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OP: You may not need a puller to separate the taper of the ball joint from the steering knuckle. If you look at the upper portion of the steering knuckle you'll see a protruding "boss" facing outward towards the tire sidewall (see pic). About 99% of the time I can just smack this boss with a BFH and release the ball joint from the steering knuckle.

* Lift the side of the LC you are working on and properly support it with a jack stand or suitable facsimile.
*Remove the wheel/tire.
* Place a jack under the lower control arm and raise the control arm(s) about 1/2 way through their travel and leave the jack in place.
* Using a ratchet strap or similar wrap it around the steering knuckle, just below the boss, and tie to the front part of the frame or anchor point to support the steering knuckle once you separate the ball joint from the knuckle.
*Probably a good idea to remove the ABS sensor wire from the upper control arm so you don't risk stretching it when you get the UCA separated from the steering knuckle.
*Remove the cotter pin.
*Remove the slotted nut from the ball joint
*Whack, using a large heavy hammer also known as a BFH, the boss...no not that boss :lol:...on the upper steering knuckle. Might have to do this repeatedly until the shock wave of the hammer blow separates the ball joint taper from the knuckle.

R&R the ball joint boot.
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Thanks guys. I picked up the rebuild kit from MxnDrnks but decided to have my mechanic install it for $20-$30. I just don't have the time right now to mess with doing this myself. I'm sure this thread will be useful to others!

Rebuild part # from Toyota: 43324-69085
Cover upper ball joint.
 
Sorry to revive an old thread, but can you do this without a press? the FSM says to remove the whole control arm and then put the ball joint in a press to replace the boot. I haven't seen anyone say for sure you can do while its still installed though....
 
Sorry to revive an old thread, but can you do this without a press? the FSM says to remove the whole control arm and then put the ball joint in a press to replace the boot. I haven't seen anyone say for sure you can do while its still installed though....

Upper boot replacement or lower ball joint replacement?

Both can absolutely be done without pulling the arm, LBJ does require either a shop press or a ball-joint press kit. LBJ info here:
https://forum.ih8mud.com/100-series-cruisers/600278-lower-ball-joint-replacement-instructions.html
 

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