Torque using X-12

[dvrasor]

ARP automotive fasteners, probably the premier
racing fastener mfg. in the country, possibly the
world strongly recomends the use of assembly
lube on fasteners but recognizes that different
lubes require different torque values. If when you
are tightening a dry fastener and you hear it
squeeking and you still think you are getting
accurate torque readings you would be wrong.

Dave Rasor

[buswarrior]

oh boy, well, here's hoping...

FWIW, from all the neat stuff I've read and the neat people I've had the honour to be in presence of....

For best practices,

We want to be sure that the threads are clean. That means wire brush, one of those smaller ones mounted in a cordless drill makes it really easy, and a spray of solvent and a rag to remove other crap.

We want to inspect the threads closely for any evidence of their being pulled or stretched. Threads not leaning out as if in a breeze, stud thinner inside where the wheel rim would be.

Good check: Does a wheel fastener run all the way in to the drum by hand? On all 10/40/60 studs?
Got some kids around? Make it a game, candy for each one to the drum? I dunno, I'm lazy and thinking out loud.... If they hang up beyond their regular travel, be afraid, be very afraid, that's where a lot of the stretch happens for over torqued studs.

Check that the mating surfaces of the rim and the drum/hub are clean, rust free, that there is no wear or elongation of the holes, and that the correct rim thickness and chamfer angles are present. Gauges for this for steel and aluminum rims are available from manufacturers.

Of particular note, paint thickness on steel rims has been found to be the cause of loosened fasteners. Both at the fasteners and between drum/rim and rim.  Home painting will leave the paint too thick, perhaps scrape it off the fastener mating surfaces, fasten the wheels, give them a squirt once they are on to seal up the metal and make them look good.

Ok, when it comes to lube, one or two drops of engine oil on the end of the stud, and a drop or two into the flange of a hub pilot system. Every manufacturer clearly states that there is to be no lube on the mating surfaces between wheel fastener and rim, no matter hub or stud pilot.

Many of us have seen those charts for degrading torque for lubricated fasteners versus dry. I have not seen a wheel manufacturer bold enough to suggest you can use those for fastening wheels.

For those of us concerned with corrosion, apply liberal amounts of stuff to the exposed threads AFTER the wheels are properly fastened. Of course, we need to clean that off for the next time with a spray of solvent.

There is a risk of losing the wheel in under torquing a wheel and there is risk in over torquing. Research suggests that lube on the threads makes unintended over torquing too easy, potentially putting the studs in jeopardy.

We want to aim for the middle, and the manufacturers and big fleets have significant liability in getting it wrong in either direction. Stick with the current best practices, and it will be hard for a busnut to go wrong.

And the thing that makes wheel maintenance easiest? Do it regularly!! Wheels that get taken off at home once a year come off easy, and go back easy. And makes greasing and inspecting everything else so much easier.

For myself, for fastening, I use the manual method, my weight out far enough on the fence pipe extension. But I've been fortunate that I have the peace of mind, and the continued youthful vigour, to have been able to pull a proper 500 ft/lb torque wrench enough times to feel comfortable that I have been achieving the same thing via simple science.

Great thread!

happy coaching!
buswarrior

[kyle4501]

There are some that firmly believe in lubing the wheel studs vs. the recommended dry installation.

I'm not a fan of dry moving contact either, but when those with the most to loose (the manufacturers) recommend a method that seems less than ideal, I dig a little to find out why.

So, with the intent of learning something -
A question for those that put lube or antisieze on their wheel studs -
What lube do you use?
What torque spec do you use?
Where did this information come from?



The cyclic loading of a wheel stud is unique on a vehicle. It goes past simple clamping (rod bolt), past thermal expansion (heads & manifold bolts), past shear (crankshaft & flywheel).
I had assumed this was part of the reason why these connections shouldn't get oiled.

Someone stated their belief that you can't get uniform results from dry threads & then admitted the use of different oils requires different torque values.
Hmmmmm,
Could it be that there is actually a larger spread in the results with oil?
I haven't ever seen an oil correction factor chart for wheel studs.
I have seen the cautions against oiling the studs.
I have seen the instructions to clean & check the studs (which many ignore).
I have seen the gauges for checking the wheel holes.


Safe travels!

[Sam 4106]

Hi Folks,
Thanks to all for your responses. I especially appreciated the one from Ed Brenner with information from the instruction manual for the X-12. I have only changed two of the four tires I need to, but I really like the X-12. My 1" drive air impact wrench will be finding a new home with another bus nut since I no longer have the strength to use it.
Thanks again for all the information, Sam 4106/MCI 8.