# 150 ft lbs of torque for a lugnut



## Bigplanz (Apr 10, 2009)

Apparently, this is the spec for a 14mm stud on a lincoln navigator: 150 ft lbs of torque. I have never, ever, known of any lug nut that needed more than 100 ft lbs of torque. So, I change a flat, tighten the lug nuts the way I always do, run them in snug with an impact wrench, then lean on them with a 1/2 inch breaker bar until my weight doesn't turn them anymore.

Wrong. Driving down a local street, 10MPH, thank God, and the wheel FALLS OFF!! Yeah, it was like that. All of that and so much more. Going slow like that, I only left a 4 foot long scrape asphalt from the brake rotor guard grinding on the street. I got out, looked at it, thought, damn. somebody must hate me to loosen my lugnuts. I found two of them 10 feet from where I stopped. Thankfully, it was a quiet side street. I managed to get the jack under the rear axle, got the SUV up enough to pull the brake guard away from the rotor so it wouldn't scrape on it, then up enough to ge the tire back on. Then, I took one lug nut off the other three wheels and put the wheel on running the impact wrench as hard as it would go. I crossed my fingers, drove slowly away, and not a peep out if it all the way to autozone to get new lug nuts. Drove slowly home, looked up the torque specs (150 ft lbs!!) and got out my 1/2 torque wrench that maxes out at 150 ft lbs, I had to stand on it to get it to click. 

Yeah, I am lucky all right. No doubt. Things learned: torque the lugnuts! Keep a torque wrench in the SUV! Keep at least one jack stand in the SUV! (The little jack looked sketchy there for a while.)


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## joecaption (Nov 30, 2011)

I've changed hundreds of tires on trucks, trailers, cars, never once had one come loose, never once used a torque wrench.
Something else had to cause that wheel to fall off.


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## Yodaman (Mar 9, 2015)

Sounds like maybe the weight of the vehicle was on the wheel when you originally tightened. The wheel was probably away from the hub and lugs won't draw it in with the weight on it.


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## Bigplanz (Apr 10, 2009)

When I changed the flat the other day, I got the car off the ground, took the flat off, put the spare on, and it was off the ground about 1/2 inch. I then put the lug nuts on, spun them on snug, crisscross, with the impact wrench. Snap, snap snap, they were all snug. The I lowered the wheel enough so the tire was on the ground enough to keep it from turning, and tightened some more. Then I lowered it all the way, and leaned on all the lug nuts with a 2 foot, 1/2 inch breaker bar until my weight wouldn't move it anymore. This morning, the spare tire was flat. I filled it with air, and the lug nuts were all on the wheel. I was inches from the wheel. I would have noticed if any were missing. I drove the car to Goodyear, to get a new tire. None in stock, we'll have it in tomorrow. I say, ok, I am driving down the street and the wheel falls off!!! Two lug nuts are in the road 10 feet behind me! WTF?!?!?!? I mean, this one has me perplexed and more than a little concerned.


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## ChuckF. (Aug 25, 2013)

Do you get along with all your neighbors?


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## Fix'n it (Mar 12, 2012)

someone at the goodyear took them loose. 

when driving on loose lug nuts, the lugs don't come off, the studs break. far as i have seen anyway.


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## de-nagorg (Feb 23, 2014)

I carry a 4 way lug wrench in my ride. and make sure that they are ARMSTRONG tight.

Was this a MAG wheel? If so they need a second torque often after a few miles.

Many years ago I had a new set of tires installed at a tire store, and was on my way, a block and a half away one of my wheels fell off, was I ever pissed?

Walked back to the store made them come and get me back on the road.

And to this day I check all my lugs myself with my 4 way before I leave their store.


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## Bigplanz (Apr 10, 2009)

Goodyear didn't touch the car. Tech just took the size off the sidewall and ordered the tire.


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## Brainbucket (Mar 30, 2015)

Yeah. You don't tighten those down, they will come off. Can't see the lugs to well but they look ok. Ford lug nut with the washer made onto it are the ones to watch out for. Aluminum rims are to be torque or you will have a vibration and/or they will fall off. Seen it to many times. Steel rims not so much. I use a torque wrench on all aluminum rims and my Ingersol Rand 231 for steel rims. I know my gun.:vs_cool: Oh and make sure the torque wrench is unloaded before you put it away. Meaning make sure it not at torque value but at 0 when stored. Leaving it at value will weaken the wrench and torque values will be off.


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## papereater (Sep 16, 2016)

150 lbs torque?? W-O-W. 
Oh- consider yourself lucky, Big, I had a front wheel fall off totally going 60 mph. I was lucky.


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## ChuckF. (Aug 25, 2013)

This happened to me years ago on an old truck I had. Unfortunately in the time it was loose, the wheel rattled around enough to ruin the GM 6-bolt steel wheel by enlarging the holes. 

I always brush a very small amount of anti-seize compound on wheel studs, just once in the time I have that vehicle. Generally, all fastener torque figures are for lightly-oiled threads, but that doesn't seem to be recommended by manufacturers for wheel studs. Your case makes me wonder if you are getting false readings because of rough threads. That might lead to the wheel rattling the loose nuts off entirely.


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## ChuckF. (Aug 25, 2013)

Another thing, look closely at the lug nut/wheel design for wear or mismatch. For example, if you have steel wheels with lug nuts with a conical section on the end, and a matching depression in the wheel holes, cracks or wear in the wheel holes, or wear on the nuts can result in the nut being tightened right into the drum/disk. That can mean that some of the 150 lbs you see on the torque wrench is being wasted into the drum/disk and not the wheel. Thus, the wheel actually is loose, and it rattles the nuts off. Look for wear marks on the nuts where there should not be any. Might have to grind a little off the very tip of the nuts.

If you have a typical mag wheel design, with part of the nut that goes into the wheel, that part can be too long and hitting the drum/disk. If it uses a washer, the washer might be too thin. Look for wear marks on the nuts where there should not be any.

Maybe your wheel studs don't have threads in them all the way to the surface of the drum/disk.


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## Bigplanz (Apr 10, 2009)

The studs are threaded all the way down the length. The nuts are the washer and nut one piece design. Damndest thing I ever saw, wheel coming off in low speed traffic. Didn't even break a lugs stud. I will have goodyear inspect the lug studs and replace any that are damaged.

I wonder why such a high torque value on the lug nuts? 150 ft lbs is axle nut torque.

Just glad nobody got hurt and the car is apparently unaffected.


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## Mort (Nov 26, 2008)

140-150 is standard for full size trucks and suvs. My 98 GMC Sierra takes 140, I torque it every time.


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## papereater (Sep 16, 2016)

Mort said:


> 140-150 is standard for full size trucks and suvs. My 98 GMC Sierra takes 140, I torque it every time.


Guess if you havent ever owned a truck/suv one wouldnt know.


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## Mort (Nov 26, 2008)

Plus, I worked at a tire shop for a year.


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## 78Vette (Nov 25, 2009)

Mort said:


> 140-150 is standard for full size trucks and suvs. My 98 GMC Sierra takes 140, I torque it every time.


Have to agree. Every F150 I've owed called for 150. And yes, they all get torqued, as do the lug-nuts on my other vehicles. Not interested in just throughing the impact at it and calling it good. Whenever a vehicle of mine ends up at the dealer for Warr. work and the wheels come off, i make sure they know that i expect them to be torqued and that i'll be checking when i get home.


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