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timmbuck2
10-20-2009, 09:47 AM
I don't want to keep the "stuck in grand junction" thread going, don't want the thread title to worry anyone. :) I want to try and figure out what is happening here, other than neglect by me in checking this on my rig after wheeling trips and before long trips.

About a 18 months ago at the 2008 wheel bearing packing party I did a complete front axle job on my 80 (I did not replace any bearings or take apart my birfs) I was late and definitely had to hurry through the 2nd half. (Please note I am NOT looking for blame or pointing fingers at ANYONE but myself. I had great mentors at the WBPP and I take 100% responsibility for any wrenching I did on my rig) Everything seemed great, then about 6 months or so later I noticed my steering was getting loose, then found a huge pile of grease/gear oil under my pass. front tire one morning. 3 of the knuckle studs were very loose, I think one was gone completely. Steering was very loose due to the steering arm being so loose. So I did another complete axle job to the pass. side, but this time I did do the trunion bearing. I put in all new studs, did not locktite them. I checked both sides at the next oil change a month or so later, and everything was fine.

Fast forward to this past weekend. With no symptoms at all, I had been driving around with only 1 stud on the passenger side and 2 on the drivers side. :eek::eek::eek: I did not check them at the last oil change. The rig is sitting at Safari Ltd. in Grand Junction with a $1500 bill to do the whole front end again, new wheel bearings and trunion bearings (said the races are toast on the pass. side, the ones with less than 12k miles on them) and everything.

My main question is how are these studs working free? What would cause this? It seems like it happens after a axle job, but what could I do to the knuckle to make these studs work themselves free?? Hugh mentions among other things the bearing preload, which at the WBPP we used the fish scale for, but when I re-did the pass. side I did it by feel.

I do take complete responsibility for not checking them and this is now going to be a regular maintenance item, but I am just trying to understand how and why it happens, and maybe prevent it from happening again on my rig or to someone else. I also am not completely convinced that my driver's side needs to be completely re-done.

Anyway, thanks for reading, and if you have an 80 PLEASE go check your knuckle studs!

leiniesred
10-20-2009, 09:55 AM
I don't have an 80, but I think my knuckles are very, very similar.

I have ARP knuckle studs. I think we go 50% more than the specified stud torque setting with the ARPs on the knuckle studs. It is hard to get them that tight, but you can.

Sure the mini guys occasionally break a knuckle, but I doubt it is due to over tightened studs. The consensus is that most knuckles break when the studs or nuts get LOOSE.

Shark Bait
10-20-2009, 09:58 AM
I had the knuckle studs work loose and shear on my 40 during Rubithon. I think if was from not re-torquing them after a while. My stupidity. But this also seems to be associated more with the 4x4 Labs hi-steer arms. Someone suggested a little tack weld on each nut after re-torquing.

nuclearlemon
10-20-2009, 10:03 AM
knuckle studs are notorious for loosening, especially as you go to larger tires, and the larger the tire, the better chance for them loosening. locktite is your friend, also checking them on a regular basis.

fwiw, i've never torqued my studs, i just loctite and crank the crap out of them and i've only had them loosen on the 40, and only once (the vehicle with the largest tires)

timmbuck2
10-20-2009, 10:13 AM
knuckle studs are notorious for loosening, especially as you go to larger tires, and the larger the tire, the better chance for them loosening. locktite is your friend, also checking them on a regular basis.

fwiw, i've never torqued my studs, i just loctite and crank the crap out of them and i've only had them loosen on the 40, and only once (the vehicle with the largest tires)

I did have 35's on there for the summer....


Hugh says this is the first time he has ever heard of them loosening and/or falling off?!

I am not sure I need to do anything to the driver's side other than new studs...

Bikeman
10-20-2009, 10:33 AM
I think loctite is useless on the studs. The oil seperation from the birf grease seeps out and lubes the threads. I check the torque every other oil change but they have never loosened up. Just think of the leverage put upon the steering arms esp. with oversized tires.

rover67
10-20-2009, 10:36 AM
I have been running 35's for about a year and a half now on my 60 which is my DD and wheeling rig. I checked the studs occasionally (like maybe three times in the past two years) before this last axle rebuild and never not found one to be loose. Torque wrench always clicked as if it were just torqued.

Just this fall I stuck on the Marlin hi steer setup with the last axle rebuild so that involved R&R ing the arms and nuts... I just stuck them back together again clean and torqued them up per the manual. A few hundred miles later i checked them and they were still fine.

I'm gonna start checking them like I do lug nuts now though...

sleeoffroad
10-20-2009, 11:03 AM
My main question is how are these studs working free? What would cause this?

Is this the truck that was in the accident when it got sideswiped on the wheel? If so, it is possible that the force on the steering arms elongated the holes in the knuckle where the studs are. This way, they will always work themselves loose. The same thing happens when the dowel pin and stud holes on the hub get elongated.

Inukshuk
07-23-2011, 01:38 PM
Good old threads never dies. Thx Timm for starting this one here and on MUD (http://forum.ih8mud.com/showthread.php?t=326101&referrerid=13105)

I just found three PS side knuckle studs loose! I have the replacements, but will hold on those till I do the tear down and rebuild (Guess what I'm doing next weekend....doh)

80 owners - take this seriously.

coax
07-23-2011, 03:02 PM
Yes indeed! One other bit of info that may be worth noting: If you switch over to the new style torx studs, its good to keep that female torx bit in the cruiser as (iirc) the new studs are not long enough to get a double-nut on to tighten a loose stud. Unless of course you removed the whole arm.:)

timmbuck2
08-04-2011, 10:53 AM
80 owners - take this seriously.

PLEASE take seriously. :) Still can't believe how "lucky" we were when this happened....

Inukshuk
08-04-2011, 09:30 PM
Last Saturday I redid that PS knuckle. The new studs are in and the torx bit is in the toolkit. Its so easy to check for tightness that it will now be part of my routine checklist.