Why aren't all our wheels falling off/all hubs or discs warping?

[BiggusDickus]

As I have my new tires installed, and the specialist garage carefully uses a torque wrench to finish putting on my lugnuts, I think back to all the times I brought my cars to big car center / tire dealers, where there was nary a torque wrench to be seen, anywhere. So I call my brother in law, a mechanic at various Lincoln dealers for the last 30 years, and ask, how many mechanics use a torque wrench to put lug nuts on? "None". So it begs the question: If the huge majority of wheels are going onto vehicles using air impact guns, why aren't we seeing astronomical lug nut/bolt failures, or every car having warped hubs and rotors? After all, we're told how important it is to have just the right tightness, and without any added lubrication put on the threads as well.

Or does it really not make all that much of a difference in 99.9999% of the cases? In my lifetime, on the street, I've never seen a single wheel come off. I'm 61. So the amount of time I've been paying attention to other cars on the road, so that's over maybe 56 years? Zero failures seen? How many cars have I seen in that time?

I understand the reason to use a torque wrench for other areas, especially in engine building. But It sure seems that the lugs on wheels are pretty tolerant of being out of spec by a wide range.

[reelizmpro]

Given the size of the bolts/nuts, the number (typically 4 or 5 lug) and the fact they do it for a living...they probably torque by feel or have a torque setting on their power tools. With that said, I have experienced over/under torqued bolts before and have seen where wheels have came off the car online so it does happen. I was able to feel the loose bolts on the front of the car and thankfully was able to get back home to torque them to spec. I tightened them snug and forgot to go back with my torque wrench. That's why I don't like to rush when working on cars. One can do it by feel but I rest easier if all the lugs are torqued to spec. If I did it all day everyday I'd probably be able to torque by feel but it's safer to be sure. The shop I grew up in always used a torque wrench on the wheels so it just depends on the tech.

[tak7]

When I was 16 I picked up my parents car from the shop (Dodge Lancer Tarbo), after driving it like any 16 year would and shouldn't there was a big vibration in the front end. After looking I discovered the front lugs were barely on (one or two threads) so tightened them down and headed back to the shop. They admitting to forgetting to torque them (or tighten them much) and we were all thankful it wasn't worse.

[rzerob]

I have personally been driving a car when the wheel fell off because of improperly torqued lug nuts.

I borrowed my grandparents suv and was driving down a hill and I felt a horrible vibration and instantly realized what it was. I started slowing down and gently steering to the side of the road hoping I would make it in time but just as I was completely stopped the wheel fell off.

I am just glad that it happened while I was driving and not one of my grand parents. I found later that they had a flat couple of days earlier and apparently the guy never torqued them down.

Also I have turned wrenches for 10+ years in dealerships and independents and always used torque sticks on my impact gun to torque lugs unless a customer specifically requested I use a torque wrench.

[Stanley Rockafella]

This one time I was driving a rented 2011 Impala (brand new at the time) thru the mountains. There was no shoulders on these roads and everyone was driving fast (including myself). After a few turns I noticed a vibration in the steering and the back end of the car. I finally found a place to turn off where I found almost all of the lugs were starting to back off.

scary stuff.

True story!

[ThatOneEuroE30]

Why aren't all our wheels falling off/all hubs or discs warping?

From general experience most lug nuts/bolts go on at about 80-85 ft lbs or are within 10 ft lbs of it so most probably an 80ft lb torque stick for various sizes and just use that. Thats what i generally do is hit it with the torque stick. They also say that after 5-10 miles the wheels should be re torqued to ensure that they dont loosen and are sitting flat on the hub but you never ever see people come in after 10 miles to have wheels re torqued.


Btw your screen name made me lulz. Cant believe it hasnt been mentioned yet. R3v is slippin

[E30 Wagen]

When I worked at a tire shop we never used a torque wrench, just the impacts. I remember one time I forgot to tighten the lugs on a van but just before backing it out of the garage my boss noticed and stopped me. That scared the crap out of me so I pretty much always triple checked every lug from then on. I bet the reason it's rare for wheels to fall of is that an impact will likely force the lugs on so tight that it's impossible to get them off without using an impact gun. We had a few complaints from customers telling us we put them on too tight but that's better than getting a call from an irate customer telling us his wheel fell off.

[mr2peak]

The vast majority of shops use a torque limiting extension. It's a thin extension that bends once the desired torque level has been reached.

These guys

[Kershaw]

I torque my lugs by feel with my impact gun and then check it with a torque wrench. Usually 13-14 out of 16 will click immediately and the rest will be at 75ft/lbs. So not a big deal. I have been meaning to buy a set of torque sticks though.

[ThatOneEuroE30]

The vast majority of shops use a torque limiting extension. It's a thin extension that bends once the desired torque level has been reached.

These guys

Otherwise known as torque sticks

[e30crazie]

I used to work at Sams Club when I was 19 and we used the torque wrench on every car no exceptions. But the smaller shops are impact crazy and have seen them break the lugs.

[UlrichFennec]

I've always used torque sticks with my impact on wheels. Usually don't use my impact for much beyond breaking loose stubborn bolts that are rusted on when I'm doing alignments or stubborn caliper slide bolts.

I like my torque wrench and use it religiously, though. Even after using a torque stick for wheels, just in case.

[TobyB]

Most reasonably sensitive, experienced mechanics can get things torqued to within
10%. Being a sensitive guy myself, I only use the clicker on the race cars....

Haven't lost a wheel...yet...

t

[pandaboo911]

Most reasonably sensitive, experienced mechanics can get things torqued to within
10%. Being a sensitive guy myself, I only use the clicker on the race cars....

Haven't lost a wheel...yet...

t

Funny, I torque my wheels twice around each time I swap. Lost 2 wheels on track so far. Though not because of the wheel nuts.

[Exodus_2pt0]

Never used a torque wrench for the 10 years I made my living turning wrenches(on wheels). If a shop requested, I would use torque sticks.

I also didn't hammer the shit out of them.

I've seen people that should be banned from power tools all together. Some people are just mechanically numb.