I do a lot of my own automotive maintenance, but some jobs require taking it to a professional.  I have a local guy that does great work, but doesn't do things like alignments, etc.   I recently replaced a tie rod on my truck after finding the ball joint was shot.  Took it to the dealership to get the alignment done.  They found another bad ball joint so I said go ahead and fix it while you have it.

Get the truck back and I notice a pretty loud grinding noise from the right front.   I get under the truck and see the rotor dust shield is bent all to heck and rubbing against the rotor, which is already wearing a groove into the rotor.   So I decide rather than take it back to have them fix it (they didn't care enough to do it right the first time), I'll just remove the wheel and bend it away form the rotor and go on with life.   I charge up the 35 gallon air compressor and proceed to start removing the lug nuts.  My 1/2 impact won't even touch them, even when cranked up to 120PSI.   Normally it has no problem buzzing them right off after I've worked on the truck.   So out comes the lug wrench and I decide to do it the hard way.

About 1/2 of the lugs on each side required me to jump up and down on the end of the lug wrench to break them free.  Do the math but I'm just shy of 200lbs and the wrench is probably something like 18".  The others I could get by hand with a two handed grip and basically assuming a dead lift position and pulling up on the wrench with both hands to get them to budge.  It wasn't an "easy" pull either...it took a pretty good grunt to get them to budge and when they did it made the typical screeching noise of a nut/bolt that was extremely tight.  I'm estimating these were well north of 300lb-ft, and the spec is 120 to 140 lb-ft.

I know what they did, the typical "good n tight" job you get anytime you go to a larger shop where the mechanics are trying to shave some time so they can get another job or two done in a day.   Probably a 3/4" impact at full air pressure and hammer home for a while.

This pisses me off for two reasons.  1), It is way too tight and I could tell the threads on the studs are now deformed.  I'm concerned that the threads have yielded and I may eventually twist one off. 2)  If the truck was to have a flat on the side of the road, it could have been extremely difficult to make the change in an emergency, especially if my wife was driving, who knows how to change her own tire.

Is it that hard to look in the manual and torque to spec?   The concerning thing is this is a 3/4 ton truck with 8 lug hubs, so pretty stout stuff that is likely more able to take that abuse.  If this was a car I'd say it would have absolutely stripped or broken the lugs.

Could be worse.

Ask Ron White.

Quantity over quality work environment

No one was ever sued over lug nuts being over-tightened. They will sue the shit out of you for under-tightening them.

Seems like another good reason then to torque to spec vs. just let them hammer with an impact.  Heck, I'd even be ok if they went to 120% of spec to ensure they weren't "loose."

Most shops require torque sticks to be used.  I'd let the dealership know about this.

Just a guess but your truck probably specs the torque 120-150 ft lbs.

Putting the wheels on a bit too tight won't get you fired.

The opposite of that might.

Cheaper to replace a stud and a lug nut, then all the damage, potential injuries/deaths from a wheel falling off...

That makes sense until you think about it for 5 seconds.

Tighten to the manual-specified torque value.  Now the job is done right and you've got a good CYA story.

If they want to sue someone, they can go after the manufacturer.That's realistically whom they'd sue anyways, since they have the largest bank account.

I’ve only seen one guy use a torque wrench on wheels. I’ve had them put one tight enough my Milwaukee 18v wouldn’t loosen them.

Especially if it falls off.  It falls off.  It falls THE FUCK OFF.

Meh, 3 foot breaker bar requires lil effort on over tightened lugs

Torque specs for passenger vehicles and light trucks are anywhere from 80 to 150 foot-pounds.

Easily manageable by an average sized healthy man with a decent lug wrench.

If your mechanic does not use torque sticks (the right one!) or hand torque with a torque wrench, you need to have a little chat with him or his boss.

I WATCH the mechanic hand torque the nuts when putting a wheel on my car.

I've had to replace broken studs in a hub before.  It's not really a very fun way to spend an afternoon.

It’s laziness.

They put the air wrench on it and hammer it until it’s tight. They don’t use a torque wrench and they don’t check torque values when they’re done. It’s lazy and fast, but it overtightens the nuts.

How big are you OP?

I've had a ton of people come in over the years and complain that their lug nuts were too tight only to find out that they just weren't giving it enough power. Generally, I'll snap off a stud before I can't get the lug nut off. With wheel studs, I had a Volvo which broke several sockets and I couldn't remove. I did use a 6' cheater pipe on the breaker bar for that, but still nothing.

Either, way you should be able to get it off without jumping on things. That can seriously injure you.

I know the service manager so was going to call him tomorrow about the bent dust shield anyway, so guess I'll mention this too.   Yeah, spec is 120-140.  I click mine off typically at 130 and usually recheck after a week or so.

Irony is that I started using the dealership for alignments after I've had 2 other local shops really struggle in the past.  One aligned it without straitening out the steering wheel first so it was about 10deg off center.   Took them 3 tries to get it right.  Other shop for some reason had to take the brake calipers off and when they put them back on left the slide bolts loose on the drivers side.  Fortunately the guy at least hand tightened the bolts a few threads so the caliper didn't come off the bracket.

Seems like it harder and harder to get good service.   The local guy I use that works for himself does great work and really wish he'd get to the point of being able to put in his own alignment rack.

Tightening torque does not equal the torque required to break them free. I used to have people complain after I would torque something to like 140 by hand because their impact and/or air supply was garbage and they were probably all done in their backyard by feel before.

Are you aware the breakaway torque needed to loosen a fastener can be considerably higher that the installation torque? Especially one that lives in a corrosive environment that is heat cycled.

Not uncommon for 3/4 ton and above to be 140-160 ft lbs on the lugs.  F series lugs with the serrated washer can be a complete mother fucker.

Your life must be worry free if you're fretting about lug nut over torque.

jeez..next time ask your wife to undo them for ya

I am a dealer tech and I use a torque stick on every wheel I install. I occasionally check with my torque wrench after. I have seen plenty of guys just keep hammering away with their gun and no torque stick. There is a shortage of techs so you will find those crappy techs at every dealer and shop.

You can replace a stud on most applications in under 15 minutes.  Torque sticks are bullshit, use a torque wrench.

6' 1" / 195lbs.  Former college football player and still in pretty good shape.   This was not a lack of "effort" on my part to get them off.    If I can't get them off with the factory lug wrench with modest effort then they are WAAAYYYY too tight.

Seems like the shop is taking a lot of risk by tightening them as tight as they have.  Yielding a lug is a great way to make things unsafe.

Tomorrow I'm going to look up the specs on the studs and see how much design margin there is.  My hope is that for a nominal spec of 120-140 that something double that value (my own estimate) that the stud didn't yield.   Most bolts don't have a 2x design margin and some start to strip at 50% overtorque...

Yep, I'm an engineer by trade.  I'm judging this based on what the break away is like when they are torqued to a proper spec.   If I wasn't so mad I should have scribed a few and done a torque back to mark test to see just how high they really were.

This

I'm sorry that you feel that way and didn't read any of the actual thread.   When torqued correctly she actually can do them on her own.

For at least the last 10 years any mechanic worth a shit has used a torque stick.

See my other post...even more reason to do it right and to spec.

It takes nothing to use a torque stick.  After warranty work I cracked an impact socket (Kobalt brand) removing a wheel.  Idiot's think tightening with an impact is a good idea...

My owner's manual specifies the torque and importantly that they have to be re-torqued after a distance (100km). When I re-check them there are some that are loose every time. Same for my wife's car. So if a shop torques them to the correct torque, and I'm a little old lady or whatever that doesn't go back over them later, there would be an issue.

Easier to ugga-ugga it on with an impact then use a torque wrench

But... you didn't actually check the overtightened lugs to see how tight they really were?

The last time a dealer touched my car it was for a major recall that required the oil to be drained (head gasket replacement).  I had to use a 2 foot breaker bar to get the oil drain plug off when I changed the oil a few months later.

I just laugh when people say they only take their car to a dealer "because they will do it right."  You are rolling the half ass work dice no matter where you go.  A torque wrench takes an extra 30 seconds, so just tighten the fuck out of it instead lol

So going 2x or more times the spec is the answer?

Unfortunately i didn't, so probably should have scribed a few on each side and torqued back to spec.   But normally torqued lugs do not require the owner to jump up and down on the lug wrench to break them loose, especially after only a few miles.

Yes, I am 100% basing the over tight based on years of working on this vehicle myself and torquing to the correct spec, plus my engineering degree, plus several years of experience as as service engineer that helps write field service manuals.

You're very concerned about tightening specs except for this specific situation where you completely guesstimated how tight the lugs actually were. Even though you intend to complain about it.

Its because dummys will feel the front end wobble and just keep driving till the wheels fall off. The mechanic probably hit it with the impact till it was tight. I personally use a torque wrench but know people who don’t and they always go over the required torque. Most dealer mechanics are probably trying to get jobs done as fast as possible and he bent your dust shield and didn’t make sure to bend it back.

Yep, having to jump up and down on the factory lug wrench is too tight.

The mechanic was probably just lazy and hammered them home with an impact without a torque stick. It's not only a good way to damage the studs, but also to warp the rotors. I see overtightened lug nuts on a regular basis.

That said, I doubt he got out a 3/4" impact for this. The amount of torque a quality 1/2" impact puts out is pretty amazing.

I'm also guessing you probably don't have a very good impact if it wouldn't break them free. Mine will snap the studs off if it can't break the nut free. I've never had one either not come free or not break.

I wouldn’t mention being an engineer to a mechanic
It would take a lot to mess up a stud if you ovetighten it depending on the gun you use. The electric impact that I use, I would have to keep using long after it tightened to cause damage.

You are lucky OP!

Years ago went to a tire shop for new tires. I asked them to torque the lug nuts to the right spec. Caught them hammering them on full impact. So I asked them to remove them and torque them. The first one they tried twisted off. Lucky me, they have nothing in stock. Get home and end up breaking every damn lug nut off. Had to replace them all obviously.

I use a 1/2" Craftsman professional.  Definitely not the top of the line, but also not harbor freight.   First time In 15+ years that it hasn't been able to break lugs free on any of our vehicles, and has no problem with in the past with stuff up to around 200 lb ft.

Maybe he used a 1/2" high quality impact, maybe it was 3/4".  The point didn't change, these were much too tight.

If you're an engineer you know there's a safety factor built into any fastener torque and it's generally at least double that spec.

"I eyeballed my lug studs and they're past the yield point and entering plastic deformation..."

Funny how everyone is a "mechanic", yet they don't do their own work and bitch about everything.  First rule of being a mechanic, hate everyone.

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Tire places are bad for that. Everyone that I’ve talked to that had a tire come off has been after a tire place visit.

Ha ha...don't worry, I get it every single day at work too.  :)   "Those stupid engineers don't know what they are doing and have never worked on anything in their life."   I just happen to be one that has and usually after jumping in and turning a few wrenches with them that goes away pretty quick.  I've also worked with a lot of engineers that gloss over when we start talking righty-tighty lefty-loosey.   We usually then ask them if we should specify a standard or metric adjustable wrench in the manual just for fun.

I'm not going to pull that one at the dealership, I know the service manager and most of the staff there so will use my personal credibility with them, not my diploma.  

Any idea what design margin wheel studs typically have?  A lot of the stuff I work with usually has the torque spec at 70% - 80%  of yield strength for good clamp load and resistance to self loosening under vibration, so there isn't a lot of margin.

Lol sorry man. The harbor freight probably would of been better.

Not typically, usually torque specs on traditional fasteners are in the 70-80% of yield range.  I know wheel studs won't be that high and certainly aren't going to be intentionally torqued to yield.  That's why I want to look these up to see if there is more margin there.  Perhaps the engineers took into account that a mechanic was going to put them on with an impact to something way over spec.

The point about the threads appearing yielded is very much something you can see by eye.  Either the pitch starts to change where they started to yield, or you see other signs of deformation.  These appeared to ave increased pitch.

I don’t know honestly but its way higher then the required torque. Alot of times when the studs get messed up is because they hit it with a gun without putting in the nuts by hand first and cross thread them. If you’re worried about it, I would ask for new studs. I imagine if you have a good relationship, it won’t be a big deal.

Dealership tech here.  I use torque sticks on everything.