Lugs torqued too much?

Mechanic used impact driver to tighten wheel lugs and said driver is set to 110 ft/lbs. I backed them off and torqued to 85 when I got home. Do you think studs are damaged?

 

No

 

I would be more concerned that the alloy wheels were deformed at the lug holes.

 

I’ve got steelies.

 

Metal will deform when overtorqued.

 

As long as you can torque them to spec now then I would stop thinking about it

 

Millions of vehicles drive the road daily with their lug nuts just ugga dugga’d on with an air gun. I know when I worked at a tire shop in college we never once torqued a lug but. A quick brrt brrt and send it out the door.

 

I've read somewhere in this forum that over torquing the lug nuts can possibly warp the drums.

 

That's true but,
A.) you need to drive around like that for a bit to warp your drums/rotors
B.) if they were warped you'd feel it.

 

Omg…never torqued a lug nut “to spec” in my entire life. Don’t worry about it.

 

So you don't think over torquing is a problem? Drive a ford or Dodge with overtorqued lugs and see how long the rotors last before the brakes start pulsing. Likely the only reason that's not been an issue for you yet is Toyota rotors are very good about not warping but they're not immune to the problem.

 

You're missing out.

 

There is Always a risk that the studs have gone beyond their "Yield" point and have been weakened.
I've seen studs Fail just torqueing them to 85ft/lbs. due to anti-seize or oil contamination. Torque is relative to several factors.

So the simple answer is YES! They may have the potential to have gotten damaged from over torque.
However, if you were able to torque them to 85ft/lbs and got good solid feedback from the torque wrench on each stud? They should be fine.
Good shops will run the lugs in with the impact and use a proper torque wrench to finish.

As a general rule, Impact guns are for Removing bolts/nuts/studs etc. (I would never recommend them to be used for "Final Torque")