It's normal for lug nuts to get loose over time, so it's a good idea to check them — especially any time a wheel has been off the car, like when a car is brand new. Here, I provide an instructional video that shows the procedure, and below that there's much more information for people who don't have a torque wrench and/or haven't done this before.
First of all, it's best to check torque when the car hasn't been driven recently. I always let it sit overnight first.
The reason is that driving and braking causes heat to build up in the wheels. Heat causes expansion, and the wheel/hub connection is tighter under those conditions, but you want to do this procedure when it's cool and in its loosest state.
I showed in the video what socket I'm using on these lug nuts — as well as some useful information about protecting the carbon ceramic brake rotors — but I didn't mention the correct lug nut torque. You can see in the following photo from the owner's manual that for C8 Corvettes it's 140 lb ft.
When I purchased my torque wrench, I was careful to choose one where 140 would be in the middle of its range. In this case, my torque wrench's range is 50-250, so 140 is pretty much right in the middle. I don't have proof, but to me it stands to reason that the closer you get to the extremes of the wrench's range, the less accurate it will be.
Did anyone notice anything strange about those three photos?
They don't use the same terminology regarding lb-ft vs ft-lbs. You can search around for more information, if it interests you, but those two units of measure are for two entirely different things. In this case, GM got it right, and the manufacturer of the torque wrench got it wrong!
Speaking of getting things wrong... before anyone chimes in to say that lug nuts must be loosened first and then tightened and re-torqued, I acknowledge that's probably the most accurate way, but it would take a lot more work and also require me to buy a new tool (a breaker bar, since your torque wrench shouldn't be used to loosen a nut). After speaking with an aerospace engineer who's intimately familiar with this subject, I'm comfortable with the way I do it, but your mileage may vary.
I will also say that if you remove any of your wheels yourself, when you put them back on, you should tighten the lug nuts in two stages, first to 50%, and then to 100% of the recommended value (per the aerospace engineer). That's a very small extra step to take when you've already removed the wheel for some other purpose and well worth doing, and don't forget to protect those carbon ceramic brake rotors with the included guards. Damaging one of them would be an EXPENSIVE mistake!
Always return your torque wrench to its lowest setting when you're done to prevent damage to the internal spring, and do not adjust the wrench below its lowest setting. For some reason, even though my wrench is advertised as 50-250, the scale on the wrench itself actually goes down to 20 lb-ft, and the instruction manual that comes with it indicates that, as well... one more thing the people who wrote the text for the torque wrench package got wrong.
Having my own torque wrench gives me peace of mind by allowing me to ensure that my lug nuts are secure before I go out and drive my Corvette the way it's meant to be driven!
The day I made this video, we got 7" of the wettest, heaviest snow all season, and even though I know lots of people don't watch YouTube videos to the end, I showed what my driveway looked like before I went out to clear it — which was very difficult! Also, the new ERay emblem with the eyes cut out gets a close-up moment in the spotlight. ;-)
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