knuckle stud torque

[yooper]

I'm installing FJ60 knuckles and birfs on my '76 FJ55. I bought new knuckle studs, the kind with the Torx head, and am about ready to install them. I will chase the threads with a tap and use red Locktite. Question:

What is the torque specification for the studs? I can't find it in my FJ55 or FJ62 FSM's. I'm not talking about the torque for the nuts after the steering arm or bearing cap are on, but for installing the studs themselves into the knuckle.


thanks!

 

[Waggoner5]

Thats a good question. I would lock tight and torque to 50 lbs if you can get that. I would be afraid to torque them more in a blind hole. I am not all that sure that torquing them is even necessary at all. I have used that stud in all 3 of my wagons and put them in until tight and stopped there. I have not had a failure with doing it that way. Now the nuts that go on the studs is another story. I torque mine at 80lbs. Slightly more that Toyota reccomends. I have had 1 failure but it was because I did not recheck the nuts after 2 days of wheeling.

 

[yooper]

...I am not all that sure that torquing them is even necessary at all...

I suspect that is the answer. Probably why there is no spec in the FSM. 50 ft-lbs was my ballpark feeling as well.

thanks!

 

[Cruiserdrew]

Good project Yooper. I did the same on my '76 FJ40, and have replaced the studs in my FJ60. I did the 40 first and didn't have a torque spec. I just put them in tight and torqued the nuts. They would loosen just a bit off road usually after 1-2 days of 4 wheeling. I then took it apart and found it is much easier to snug down the studs with the knuckle installed. Since then, none have loosened despite a 4 day run on Dusy-Ershim and another run through the Rubicon.

My FJ60 I waited to snug the studs untill after the knuckle was installed. Those have never had to be re-torqued and I've checked them several times. I did not use locktite. There are pros and cons of the locktite approach, in that if you do break one off, it will be difficult to retrieve the locktited broken piece. I have heard people with tons of experience reccomend both ways.

 

[yooper]

I can't find my 1/2" to 3/8" adapter for my torque wrench, and I don't have 1/2" drive 9mm socket, so I ended up just putting them it pretty darn tight with the 3/8" ratchet and red locktite. Seemed to work okay, with one knuckle fully installed on the truck so far. I put the knuckles in a vise to put the studs in, so it was as easy at having it on the truck. I may go back and retighten them with the torque wrench later - I'm thinking that even if there is no spec, at least all 8 studs should probably be evenly tight.

I could go both ways on the locktite myself. Yes, it would be hard to remove a broken stud that's locktite treated, but my feeling is that they generally break when they become loose, so if it doesn't get loose it should be much less likely to break in the first place. I guess I'll find out!

thanks guys!

 

[nuclearlemon]

just out of curiosity, has anyone replaced the studs before they've broken? would it be advantageous? i broke one, one's a tad buggered, so i was just thinking of replacing all four while i've got it apart.

 

[Cruiserdrew]

just out of curiosity, has anyone replaced the studs before they've broken?

Yep Ige-Every time. The 40, 60 and 80 are all running on the upgraded studs. As I build my 71, it's getting the chrome moly ones due to the added stress of the high steer.

 

[euclid]

What's the magic word you say to the dealer to get the torx head knuckle studs? Or do you just get them when you order replacements?

 

[Bomar]

We recommend using Locktight on the lower threads when installing knuckle studs. Studs should be tightened to 20-25 ft-lbs in the knuckles. Stud nuts should be tightened to 80 - 100 ft-lbs.

From Trail Gear site.

 

[euclid]

What's the magic word you say to the dealer to get the torx head knuckle studs? Or do you just get them when you order replacements?

Seriously, what's the source for the torx knuckle studs?

 

[VETTE60]

Seriously, what's the source for the torx knuckle studs?

they have them in both torx and 6point. the torx are stock strength and the 6 points are stronger,
they are ARP's and you can get them from trail gear. not cheap, but stronger

here: http://trail-gear.com/knuckle-studs.html

 

[Cruiserdrew]

Seriously, what's the source for the torx knuckle studs?

Dealer item-Cruiserdan gets them for me.

I've also seen them for sale on Marlin Crawler's website.

 

[Hamachi]

I just bought some 60 studs from the dealer. The threads that go in the knuckle have green stuff on them. Do you guys know what this green stuff is? I thought it was a form of locktite.

 

[OGBeno]

I just bought some 60 studs from the dealer. The threads that go in the knuckle have green stuff on them. Do you guys know what this green stuff is? I thought it was a form of locktite.

Correct. This is the updated part number that integrates thread sealant.

 

[Hamachi]

Correct. This is the updated part number that integrates thread sealant.

So no need to use red locktite?

 

[OGBeno]

So no need to use red locktite?

No.

 

[Hamachi]

No.

Cool. Thx for your help.