When is the last time you checked your steering arm knuckle stud torques?

[Bud_Dude]

So while crawling around in an internet rabbit hole researching something completely different today, I forget where I even started now... Oh yeah... I was the 'Pin 7 Center Diff Mod'... I stumbled onto the subject of Steering Arm Knuckle Studs.

Out of curiosity and once it cooled down outside here, I slid under the truck and found that I got about half a turn out of each of the four accessible stud nuts with my torque wrench set to about 75 ft-lbs, though some say 80+ lbs is appropriate. So they were loose... The problem now is accessing the two outer nuts closest to the brake dust shield. Anyone know a trick to accessing and torquing the nuts closest to the brake dust shield without tearing down the whole damn birf to remove said shield? Just pry and bend it out of the way with the wheel off?

From my reading this is an offroad field repair just waiting to happen and not a fun one... So I wonder how many of us have actually checked this from time to time? We've seen all manner of other carnage and malfunctions offroad, I wonder if a broken knuckle stud has impacted anyone yet...

• Broken Knuckle studs with >35s & How to prevent it - https://forum.ih8mud.com/threads/broken-knuckle-studs-with-35s-how-to-prevent-it.951678/
• How to Properly Install Toyota Steering Arm Knuckle Studs - https://www.roundforge.com/articles/how-install-maintain-toyota-steering-arm-knuckle-studs/

I'm now thinking it might be wise to do an inexpensive knuckle stud upgrade on my truck for this simple yet so critical component. Then I'll have eight spare studs and nuts for field fixes in the future...

• Get the Strongest Toyota Knuckle Studs - https://www.roundforge.com/articles/upgrade-toyota-knuckle-studs/

 

[badsamaritan]

In opted for the newer style studs when converting to disc on the 40, I got the Toyota PN from Beno and ordered them. I considered the ARP ones but I liked the idea of the torx head at the top of the stud.

If anyone is about to do this, I have some extra OEM cone washers from mine. I ordered extra on accident.

 

[Outsane]

You can also get wits end nut huggers from @NLXTACY

80 Series Nut Hugger- Toyota Solid Axle Knuckle

80 Series Nut Hugger- Toyota Solid Axle Knuckle (SAK-1)

absolute-wits-end.com

 

[Bud_Dude]

You can also get wits end nut huggers from @NLXTACY

80 Series Nut Hugger- Toyota Solid Axle Knuckle

80 Series Nut Hugger- Toyota Solid Axle Knuckle (SAK-1)

absolute-wits-end.com

Thanks, I saw those during my web crawl, it seems that like castle nuts and safety wires, these will keep the bolts from unscrewing but won't necessarily ensure the bolts remain at the recommended torque, ensuring the adequate compressive force and friction between the steering arm and knuckle. The main failure mode appears to be that when the bolts become loose and the friction between the steering arm and knuckle is reduced the steering forces can potentially shear the bolts. There are lots of recommendations for cleaning the knuckle stud threads during stud replacement and putting in new or stronger bolts along with Red Loctite (2620), then using the Loctite on the nuts as well when torquing. Understanding that Red Loctite when properly used with clean metal can make for very difficult disassembly if and when that time comes, possibly requiring substantial heat to get things back apart. The pros and cons of the options probably makes for an interesting study for a mechanical engineer, but I'm an electronics nerd...

 

[bicycleagent003]

I check those steering arm nuts before and after each wheeling trip, or at least I try to. Getting a torque wrench on the inner nuts is no issue. As for the outer, up against the brake dust shield, I haven't figured out a way to get a socket in there. So, I just use a 12 point box wrench, and then put another wrench on the open end of that one, and put some serious pressure on it. I realize I am not getting a measured torque setting on the outer nuts, but I am making sure they are darn tight. And if I break one (I don't think I'm putting that much force on it, but I am pulling hard, and things can let go), I'll just go in and replace the stud. I'd rather do that repair than have a catastrophic failure on the highway.
YMMV.

 

[Dissent]

Does anyone know what knuckle side thread size and pitch are? Looking to pickup a tap to keep on board.

 

[Loober]

M12x1.5, the nut side is m12x1.25