Adj. CA's Need lock nut?

[HaleYes]

What's the general opinion on weather or not a lock nut is needed on the adj. threads of CA's? Both ends are mounted, it's not going to lengthen/shorten on it's own...right? Over time if a lock nut isn't used, I suppose it could waller-out the threads..right? I need to decide if I need to find some lock nuts or not on my newley aquired CA's. They did not come with them.

TIA guys.


Haleyes

[Mr.OverKill]

imho no you dont need them because all they really do is keep them from having a 1/10,000 of an inch play ( or something like that ) and the wear would be minimal

just my .02

[rstarch345]

It depends on whose you have. Rough Country CA's don't use or need them.

[Kejtar]

I think it might depend on what ends are used: if you're using bushings then you might be able to get away. If you're using something like RE superflex joint on one end I think you want a lock nut so that it stays in a particular orientation while static: otherwise the joint might just get all crooked and wedged in the mount.

[HaleYes]

Rusty's uppers and lowers, so there OEM bushings.

[CRASH]

You must use lock nuts on any sort of threaded part, with the exception of an Acme thread.

Threading that is not preloaded with some form of tension device will not only have a tendancy to move parallel to the loading, but also perpendicular to it. Because of the play inherent in all threaded parts, the stress is pulling the threading in and out, but also causing a binding load. This will quickly wear the treads, and has the potential to actually split the treaded sleeve if loaded heavily and repeatedly.

[HaleYes]

You must use lock nuts on any sort of threaded part, with the exception of an Acme thread.


Rusty's are ACME thread. Why are ACME threads the exception? Would it be a bad thing to use a lock nut on ACME threads?

Thanks for the info.:wave:

[ChiXJeff]

Crash managed to eloquently state what I've been trying to put into words for the last couple of hours.

The difference is in the thread profile. Standard bolt threads have (relatively) sharp corners. Acme threads are more square, and have a flat top.

There's a bunch of info available on the 'net (Google can help) and a good machinist's handbook should shed some light on the matter.

As far as personal experience goes, I've got RE adjustable arms on mine. I didn't realize that a jam nut had come loose, and that's what was making a clunk. By the time I'd figured it out, it'd jammed itself firmly together. Normally, I'd say this wasn't a problem, but I was trying to adjust wheelbase at the time.

[ZPD]

You must use lock nuts on any sort of threaded part, with the exception of an Acme thread.

Threading that is not preloaded with some form of tension device will not only have a tendancy to move parallel to the loading, but also perpendicular to it. Because of the play inherent in all threaded parts, the stress is pulling the threading in and out, but also causing a binding load. This will quickly wear the treads, and has the potential to actually split the treaded sleeve if loaded heavily and repeatedly.
x2

Although I at one time had rusty's UCA and I used a locknut because I was tired of the clunking.

[tealcherokee]

if you put a lock nut on rustys junk arms, er uhh...control arms, because they dont use a flex joint, the arm would bind one way, and undo the lock nut the other

[stupidfast]

rustys claims that you flex better w/o the lock nut becasue the twisting of the threads adds to the flexing. it all sounds half assed to me. and they cant stop saying that if you dont run the lock nut then you need to grease it like crazy. i think its all crap. and i dont think that rustys runs acme threads.. as far as i know.

[HaleYes]

and i dont think that rustys runs acme threads.. as far as i know.

The lower adjustable control arms are fabricated of .250 thick 2 inch DOM tubing and have a formed mandrel bend to offer more flex and articulation. 1.5 ACME threads are used to give strength, adjustably and to offer a twist type articulation. Factory OEM bushings are installed and are powder coated in a glossy black finish. Our adjustable arms give about 4 inches of adjustment. We highly recommend using a lithium grease in our control arms and be sure to pack it full!

[ZPD]

I used his UCA in my long arms (radius style) so no twisting was needed. It did have acme thread and it did clunk all the time due to the large backlash.

[Randy_66]

Why are ACME threads the exception? Would it be a bad thing to use a lock nut on ACME threads?:wave:

[HaleYes]

I've got a clunk now. Hard to tell where it is comming from too. It's pretty loud as well. It may very well be the CA's, but I'm not sure yet. It seems to only happen when I'm turning and going up/down a slight grade. It's just one clunk. Does this sound like symptoms of a CA clunk?

[BigBlueXj]

i run rustys la kit fortunatly i greased th shit out of them since day one and they havent gotten sloppy even after 40,000 hard miles. however they can wear and clunk, id also check the sway bar bushings they can make some killer clunking noises when bad.

[seanR]

I've got a clunk now. Hard to tell where it is comming from too. It's pretty loud as well. It may very well be the CA's, but I'm not sure yet. It seems to only happen when I'm turning and going up/down a slight grade. It's just one clunk. Does this sound like symptoms of a CA clunk?
You didn't put nuts on them did you? :twak:

[BigBlueXj]

no mine r still good, but i do replace my sway bar bushings every year, looking into an anti rock set up

[jcamp1221]

I installed new Rusty's upper and lower ACA's and had loud clunking on both side depending on what side hit something. I installed locknuts with acme threads on the lowers only and the clunking is gone.

[HaleYes]

You didn't put nuts on them did you? :twak:

No, I did not.

[mikecooper]

I had rustys adj uppers and lowers until i got my tnt kit, and those bastards clunked after about 3 months. I greased them at least once a month if not more. Since ive had my tnt kit on i havent a single clunk. When i was under the jeep and pressed up or down on the ca's i could see movement. When i called rustys he said to ship them back and they would fix or replace them but it wasnt worth my time so i gave them away and bought a tnt kit.