Upper control arm striking shock phenomenon
 

Most of us have read about the condition in which a worn out shock no longer limits wheel travel and the UCA strikes it and can puncture the metal and airbag....

...anyone ever hear of this happening with stock sized tires?

My 2006 has way worn out shocks. We were on a beat up forest service road Saturday when I realized just how bad....but no striking of the UCA.

Theory: LR designed for this, and only the additional unsprung weight of a larger tire causes the interference.

Thoughts???

So your saying that a worn shock when fully compressed allows the control arm to contact the Spring body?

Never heard of this, links to previous discussion?

You haven't? That's surprising! I will go back and try to find links when I have more time. Long story short though, yes that's exactly what happens. Without the shock limiting wheel travel, and possibly with heavier tires as I now theorize, the UCA hits the outside of the shock, eventually can puncture it, and put a hole in the airbag at which point you are FUBAR. You'll be at bump stops and no way to hold air in that corner without some kind of patch.

It happened to me, off-road....and I was running 275/65s. Snapped my swaybar end link, too. Happened to another gent on one of the message boards, SAME thing, swaybar link snapped. In my case I caught it before the bag could get struck; got it back up, pulled EAS fuses and took it real easy on my way out of the forest.

Are you sure the sway bar link isn’t getting snapped and puncturing the bag?

You can bottom out shocks on stock tires to. Now if we were going on adding armor which would be weight carried by the suspension that might make more sense to me. Or if you were saying that the added weight of the larger tire when the suspension is completely unloaded ie wheel coming off the ground is causing the shock or sway bar link to snap that could also be possible. Though that damage could be done by any size tire

I googled and found your two posts that was it.

I’m beginning to think you have something against oversized tires:laugh:

Hahahaha....dude, I HAVE oversized tires! :)

"Or if you were saying that the added weight of the larger tire when the suspension is completely unloaded ie wheel coming off the ground is causing the shock or sway bar link to snap that could also be possible."

Yes, THIS.

I am absolutely certain it was the UCA and not the end link. I don't think it's the SIZE of the tires that could lead to this, it's the WEIGHT. Agree that shocks can bottom out regardless. It's just a theory, because it happened to me in my '05 with the 32s but then last weekend in my '06 I was bottoming out, I could hear the shocks hitting their limit...and no contact with the UCA.

I'm really struggling to see how geometry changes with a few extra pounds. I could maybe see with worn bushings and larger tires on wheel spacers? Lots of stuff is pretty close with stock tires, let alone modifications. But the limits including bump stops shouldn't change unless someone is beyond the damage point.

Also never heard of this, and I won't speak for others, but given that, I don't think it's "well known" as you put it. Maybe stop jumping the LR3 like the multiple videos of new Raptor's on Youtube? I can see that being a problem for any vehicle.:) Not saying you did, that was a joke.:)

Found footage oh Houm-wa on the trail





:laugh:

Fair points...
 

I guess I considered it well known because at the time it was a heavily discussed topic. The geometry doesn't change with heavier tires, but I think they are more than a few pounds heavier and that could cause the extra deflection when the travel is not being limited (as well?) By the inards of the shock.

My observation is that it happened to two of us in almost the same manner and we both had overweight (just for you Army) tires....not a statistically significant sampling, I know...but it's curious to me.

Well I arguably have the heaviest tires in the discussion and even with getting the front off the ground I have had not contact. Just more proof big tires and the coil conversion is the best option :wave:




:laugh:

Coilers...
 

....would not be subject to this phenomenon.