Way over-torqued my shank/washer lug nuts - Problems?

[UCBerzerkeley]

As the title states, I have been way over-torqueing my lug nuts. I have a 95 with the shank/washer lugs. Today I used a torque wrench on the lugs for the first time at 76lbs and wow - I had been putting way more pressure previously.

Any problems I should expect or items to inspect?

 

[nicholas]

I'm positive it's happened many many times during the lifetime of my wheels under the PO's watch. Tire shops are notorious for over torquing wheels. I've even had a shop tell me that 76ft-lbs is crazy talk. I think it's less of an issue with the washer-shank style, but even still, I'm sure over-torquing can deform the holes. Some of the holes in my wheels look a little deformed, but I haven't noticed any problems with vibration etc. I'm unsure how much this has affected the structural integrity of the wheel.

 

[Paul_L]

The wheels are pretty strong, I'd be more concerned about the studs.

 

[scottm]

The studs will stretch first, distorting the threads. If the threads are all clean and the nuts still turn on hard that's a sign. Look at them carefully with the wheels off for cracks, they aren't always visible. But overall, I'd say you're safe.

 

[jlg32281]

No problem, most are over torqued.

 

[Ebag333]

If you're worried about it, replace the studs. Not difficult, and cheap insurance. Plus then you won't need to worry about snapping one off down the road. Much easier to swap them out before that happens.

 

[jlg32281]

I wouldn't worry about it at all. Even if one snaps off, you have 5 others holding on. I wouldn't replace anything until one breaks, which I suspect will be never.

 

[retrofive]

Same thing here, i goofed, and snapped a stud. Replace the stud and just have been more careful since.

 

[Tools R Us]

As the title states, I have been way over-torqueing my lug nuts. I have a 95 with the shank/washer lugs. Today I used a torque wrench on the lugs for the first time at 76lbs and wow - I had been putting way more pressure previously.

Any problems I should expect or items to inspect?

Define way over-torque. The same studs are used on the steel wheels, so 109 ft/lb isn't going to harm them and there is some margin above that before reaching yield.

There are two forms of fastener deformation: Elastic is the normal use deformation, the fastener returns to it's original size when the load is removed and can be reused almost forever, at full rated load. If the yield point/torque is exceeded, the fastener is plastic deformed. When the load is removed, the fastener remains longer than original, is permanently stretched, will never hold rated load and needs to be replaced.

The indicators I look for is the "feel" of the fastener when torqued and retorque result. The fastener should solidly torque, if it feels springy, springs/moves each time the torque wrench is clicked, it is most likely plastic deformed and should be replaced. The fastener should hold torque, when retorqued it should not move, if it continues to creep, move with each retorque attempt, it's most likely plastic deformed and should be replaced.

IMHO, plastic deformation from huge over-torque events, is one of the leading causes of wheel mounting failure. It only takes once to destroy studs, they are relatively cheap and a pretty important part, so when in doubt replace. They are often abused by inexperienced techs.

 

[Ebag333]

IMHO, plastic deformation from huge over-torque events, is one of the leading causes of wheel mounting failure. It only takes once to destroy studs, they are relatively cheap and a pretty important part, so when in doubt replace. They are often abused by inexperienced techs.

I don't know how many times I've seen tire shop guys grab the biggest impact gun they can find and drill the lug nuts on. And then hammer them on a few more times. Then maybe get a breaker bar and stand on it.