Lug nut torque

[bill61]

No, think of the lubricant acting as a pillow layer. Have to overcome that with more torque to retain the same clamping force as if the threads were dry.

I work in aircraft manufacturing and we have separate standard torque tables for both dry and lubricated threads. In all cases, lubricated threads have higher torque values for a given fastener.

I worked aerospace my whole career but never worked with anything but dry bolt torques. But your reasoning isn’t making sense to me. The lubricated bolt would rotate easier, thus applying more clamping power at the same torque load (in my mind). Kinda like this search says…

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[Hootbro]

I worked aerospace my whole career but never worked with anything but dry bolt torques. But your reasoning isn’t making sense to me. The lubricated bolt would rotate easier, thus applying more clamping power at the same torque load (in my mind). Kinda like this search says…

You are right, I got it reversed on the risk of over torque with lubricated threads as the torque reading of the torque wrench comes into play and can actually over torque going by standard values of dry threads.

As to lubricated threads, it is rare but we have a few instances of setting torque and torque to yield but that is called out in the drawing as applicable. 99% is dry torque. I just knew going off the top of my head we had tables showing different values for dry and lube and also depends on lube used.

 

[Lost1wing]

I lived in Chicago in my early years. I would put antiseize on my lug nuts and use the same torque required if dry. I moved to Georgia and tried this method on a new Crown Victoria. I tried reaching the proper torque but it was seeming like I was stripping the threads. The lug nuts never got tight. I pulled the nuts off but I couldn't see any damage to the lug nuts or the studs. I marked the studs thinking that they were spinning. Nope! The nuts were expanding over the stud threads. I cleaned the threadsof all antiseize and tried it again. All lug nuts torqued just fine. Since it was a new car, I brought it to the attention of the dealer. I actually showed them how I could just turn it forever without it tightening. The tech came out and showed me that his torque wrench did the same thing. He also said that it is to be a dry torque but that it should also torque with grease or oil on the threads. Then he showed me how he can torque the lug nuts with antiseize by speeding up the rotational force of the torque wrench. He then did the same without the antiseize. Next he under torqued the nuts by 10 pounds. The loosening torque was the same as the loosening torque of a properly torqued lugnut. I walked away at 23years of age confused at what I just saw. The old man tech that came out pretty much just said if you hit the torque value any where near what is called out don't sweat it.

He replaced 20 lug nuts for me and cleaned the studs.

 

[Badunit]

... internet has been out since last night, AC is flooding the filter area, other stuff on the fritz all at once and I've been dealing with Safelite STILL not paying us and not saying why (then find out there was a form involved I never got - but did they ask me about it? No!) Crazy here today!

I understand that. Been busy doing repairs and maintenance on several family vehicles of different makes and models, trying to catch up with farm stuff after a week of hard rain and soggy fields, multiple large trees blew down in the wind and rain and I have to saw them up and haul them off, and every time I turn around something else needs my immediate attention.

 

[Lost1wing]

I understand that. Been busy doing repairs and maintenance on several family vehicles of different makes and models, trying to catch up with farm stuff after a week of hard rain and soggy fields, multiple large trees blew down in the wind and rain and I have to saw them up and haul them off, and every time I turn around something else needs my immediate attention.

Same boat here... where's that torque wrench? Ahh forget that! For now, get them tight and retorque at the nect C-check.

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