Knuckle/knuckle arm - That's not good (1 Viewer)

[DRTDuck]

While I was cleaning the garage yesterday, I looked back at the truck one time and noticed a big glob of grease on the inside of the front USPS tire. That's not good, I thought.

Upon inspection I noticed a gap between the knuckle and knuckle arm and that all four nuts/studs that attach the knuckle to knuckle arm were loose! Well actually three were loose, because the outside front stud is missing, that is obviously were the glob of grease came from.

Perhaps this loosness is what has been squeaking when I turn left for the last couple of months.

Don't know how missed that gap over the last few months when I have been under there, but I suppose depending how the truck was sitting, it may not have shown.

So, another item to check on your regular PM schedule, nuts at 71 ft/lbs.

Will go the local dealer today to get a stud and nut, then pump so more grease in!

 

[Driley]

Greasy DS

The USDS on my 94 LC is kind of greasy. I plan on doing the front axle service in the next month of so, but am concerned with the grease loss. I am ordering the FSM next week. I would like to put some grease in there until I can tear it apart. Where is the grease fitting? I just changed out the front brakes 2 weeks ago and looked around a little, but did not really think about adding grease to it until I had the wheel back on.

Thanks,
Riley

 

[Rich]

You first have to tighten the studs. And then the nuts. Or the cycle will repeat.

 

[stayalert]

Where is the grease fitting?

no fitting. square plug. were I you I would pump grease in for short term but do full axle serive soon there after....

 

[DRTDuck]

Rich-

Thanks, yeah I tightend the studs then the nuts.


Stay-

I did a full axle service about 18 months ago, do you think I need to do it again? The grease that came out does not appear to be contaminated by oil, so in theory, I'll just be putting in what came out?

 

[snowwolf]

Well I had the same thing, when I tried to tighten mine, three out of the four had broken!!! I was very lucky, I had to remove the whole housing and remove the broken studs, I fitted the new type of studs with the torx type head so you can really tighten the studs into the housing, think the torque setting was about 85ft lbs I even used metal lock compound on the threads too, the new studs 8 in all plus the cone washers and flat washers and nuts are quite expensive, well here in the UK they are. best to do this sort of thing properly as you will loose all steering if they fail!!!!!

 

[Cruiserdrew]

Snow Wolf is right on. Those torx top studs should be a mandatory part of the knuckle rebuild process. They can really be torqued into the housing, making this sort of failure much less common. The studs themselves are not that expensive. Maybe Cruiserdan should make new studs a part of the "rebuild kit".

 

[Curran]

Snow Wolf is right on. Those torx top studs should be a mandatory part of the knuckle rebuild process. They can really be torqued into the housing, making this sort of failure much less common. The studs themselves are not that expensive. Maybe Cruiserdan should make new studs a part of the "rebuild kit".

Sage words. Those bolts are the #1 item I check after any trail run.

 

[snowwolf]

I still check them quite often, I highway drive at 80mph quite often and the thought of no steering is frightening, the black oily grease around the knuckle is one of the symptoms you get, as it does not keep the central to the seal that holds the axle oil in the diff, so it can pass the seal and contaminate the birf grease which makes it runny and ends up outside the knuckle, if you have the oily mess on the studs be sure to stick a spanner on them to check they are tight, my studs were still in the knuckle and looked ok, but as soon as I put a spanner on them, three out the four just fell out!!!

 

[wildsmith]

Will go the local dealer today to get a stud and nut, then pump so more grease in!

I replaced studs / tightened things up but they kept coming loose and eventually the holes in the knuckle became oval shaped

The only way I could fix them permanently was to remove the knuckle and clean the threads properly in a parts washer, then use a thread lock compound on the new style studs.

I think once grease gets onto the threads it's a lost cause.

Jon.

 

[yellowchaosfj80]

THIS is great! I just had the same thing on my rig. The DS was loseing grease and there was oil in the mix! I saw the 4 bolts had backed out ... did the reseals and snuged it all up . ....... But it looks like I'm knot alone in this ... What are these new Bolts you mentioned! thanks CRAIG!

 

[snowwolf]

Wildsmith is right in what he has mentioned, to do the job properly and avoid having to do it again and to avoid a bad accident, it's best to completely remove the knuckle and wash out thoroughly, I used liquid metal to lock my new studs in, I used that because I can get it free at work, very expensive if purchased, but threadlock will suffice.

 

[e9999]

last time I looked, my studs appeared to have a round head, IIRC. Not hex and saw no screwdriver slot. How do you tighten these? just with 2 nuts together?

 

[Cruiserdrew]

What are these new Bolts you mentioned! thanks CRAIG!

I stole the pic of the stud and associated hardware from Marlin's website. The updated stud has the torx. You need 8 for an 80 or 16 for a 60.

E9999-If you are going to the trouble of taking off the nut and cone washer to tighten it up, just replace the stud.

There is variable advice about locktite. I have seen the studs break several times on the Rubicon. Mudrak broke 2 sets last year, and a minitruck guy the year before. Pat Takash had a set break after Rubicon while he was on the way home. The point is, if the studs are locktited down, I don't see you having a prayer of getting the broken stubs out on a trail run. If you carry a spare pair of knuckles (I do in my 40 just for this reason) it's no big deal, but a spare pair of 80 knuckles would be $$$. I would reccomend you put a socket on the nuts every night while offroad. It's part of my end of the day routine.

 

[yellowchaosfj80]

Thanks Cruiserdrew .... thats great and I well keep an eye on them!

 

[riverliver]

My granny used to tell us boys( you little pistol packers get outside right now and try not to break nothing!)

 

[turbocruiser]

I stole the pic of the stud and associated hardware from Marlin's website. The updated stud has the torx. You need 8 for an 80 or 16 for a 60.

E9999-If you are going to the trouble of taking off the nut and cone washer to tighten it up, just replace the stud.

There is variable advice about locktite. I have seen the studs break several times on the Rubicon. Mudrak broke 2 sets last year, and a minitruck guy the year before. Pat Takash had a set break after Rubicon while he was on the way home. The point is, if the studs are locktited down, I don't see you having a prayer of getting the broken stubs out on a trail run. If you carry a spare pair of knuckles (I do in my 40 just for this reason) it's no big deal, but a spare pair of 80 knuckles would be $$$. I would reccomend you put a socket on the nuts every night while offroad. It's part of my end of the day routine.

I'm glad I just read, or re-read, this...I am in the process of replacing the studs right now, I think I'll just put them in without the locktite although if it indeed broke right at the knuckle its gonna be a bitch to get it out regardless of the locktite and if it broke like where the threads stop then with or without the locktite, you can prolly get it out with some strong visegrips. Anyways, I think I'm gonna go dry!

Ohh, yea, anyone know what to torque the studs to, is it the same 71 lbs as the nuts? Thanks.

 

[cruiserdan]

There is no torque spec on the studs. I imagine that if you tried to go to 70 lbs on that torx end you might break something.

 

[turbocruiser]

There is no torque spec on the studs. I imagine that if you tried to go to 70 lbs on that torx end you might break something.

Okay, but AFAIK the nuts on those studs torque to 70 right? I wont goto 70 on the studs but I gotta have some specific number Dan, you know OCD works that way!!! What would you torque them to just out of curiosity?

 

[cruiserdan]

I don't really know and I have been thinking about it for a few minutes. The socket is kinda small and I imagine that anything over 35 lbs or so may break it or mess up the end of the stud.

You see when you tighten up a nut or bolt the stress is spread over the face of the nut or head of the bolt. With a stud all you are going up against is the tapered end where the threads end. I can't see that taper taking the full-on torque.