Lug nut loosening torque

[ek1]

So as we all know the lug nuts must be torqued at 107 Ft-Lbs. Great! But who can tell me what kind of torque is required to loosen a lug nut that was torqued at 107 Ft-Lbs? I spent some time researching this and every article I found stated that THEORETICALLY (i.e. according to laws of physics) a lug nut torqued at 107 Ft-Lbs requires 107 Ft-Lbs to loosen it.

What happens in real life is slightly different. Since I rotate my tires after 1-2 track sessions I decided to get a cordless electric impact wrench to convert a 20-min tire change to a 5-min one. First I bought a LongAcre Racing pit impact gun (http://www.longacreracing.com/produc...y+%26+Charger).

Rated at 330 Ft-Lbs and according to the web site "pops lug nuts off easily". My ass. I own multiple LongAcre Racing tools and they are ALL top notch quality. This thing felt like crap. Cheap distorted plastic with unfinished seams all around, stickers peeling off, battery dies after 8 tire changes. The shaft was crooked. Obviously made in China. Best part? It could NOT loosen the lug nuts on the ACR.

So I returned the tool and did some more research. Settled on a Milwaukee 2754-22CT (https://www.milwaukeetool.com/power-...ess/2754-22ct) Rated at 210 ft-lbs, which is almost twice the torque required to undo ACR lug nuts. Got the tool. Feels very high quality. Very compact and practical. One problem though. Does NOT loosen freaking lug nuts! Tried it several times...no go.

P.S. I read about all the caveats - how lug nuts require more loosening torque due to being corroded and contaminated. I read how temperature difference makes lug nuts harder to undo. Forget all that. With my car sitting in the garage, turned off for days, with everything cold, with lug nuts and studs crystal clean, if I torque a lug nut at 107 ft-lbs, I can NOT loosen it with either one of the tools.

How much torque do I _REALLY_ need in a cordless electric impact wrench to undo the damn lug nuts?

[Jack B]

I have the same issue, I use a DeWalt cordless and anything over 100 ft lbs is a problem.

[Arizona Vipers]

I always use a breaker bar to loosen the lug nuts before using the cordless impact wrench to spin them off. This will make your lug nuts and your studs last much longer.
I use this- https://www.amazon.com/gp/product/B00MWVAUT6
Takes about 2 minutes to go through and loosen all 24 lug nuts with that.
I also never tighten my lug nuts more than 85 ft/lbs. If you are checking them often, 107 is way too much.

[ek1]

I always use a breaker bar to loosen the lug nuts before using the cordless impact wrench to spin them off. This will make your lug nuts and your studs last much longer.
I use this- https://www.amazon.com/gp/product/B00MWVAUT6
Takes about 2 minutes to go through and loosen all 24 lug nuts with that.
I also never tighten my lug nuts more than 85 ft/lbs. If you are checking them often, 107 is way too much.

Please explain the difference between loosening lug nuts using a breaker bar vs. an impact wrench? Tightening makes sense and I always do that with a torque wrench. But loosening? I must be missing something.

[Arizona Vipers]

If you swap/rotate wheels/tires often, you shouldn't break the lug nut loose with an impact wrench this damages the lug nut and eventually the studs as well.
Same with when you put the lug nuts on, you don't tighten them as hard as you can with the impact wrench. Put them on by hand at least 4 full turns to prevent threads from getting stripped, then use the impact wrench to get them close to tight, then tighten with a lug wrench.

[Steve M]

You are using the wrong tool...if you want to go cordless electric, you need the Milwaukee 1/2" M18 Fuel Impact (2763). I have the 3/8" version as well, and it does not come close to the power that the 1/2" unit has. I used the 1/2" to loosen the rear axle nuts, and those are torqued to 240 ft-lbs. It has absolutely no problems with lug nuts on any of my vehicles.

[Special Ed]

I always use a breaker bar to loosen the lug nuts before using the cordless impact wrench to spin them off. This will make your lug nuts and your studs last much longer.
I use this- https://www.amazon.com/gp/product/B00MWVAUT6
Takes about 2 minutes to go through and loosen all 24 lug nuts with that.
I also never tighten my lug nuts more than 85 ft/lbs. If you are checking them often, 107 is way too much.

I agree 107 is of the chart tight. In all my years of various type of racing I have never seen wheel torque numbers this high. Right or wrong I won't do it.

[bluesrt]

Please explain the difference between loosening lug nuts using a breaker bar vs. an impact wrench? Tightening makes sense and I always do that with a torque wrench. But loosening? I must be missing something.

for one reason loosening lugs with a impact a lot disfigures the lug nuts verses loosening by had due to impacting the lug I have found/ unless you have plain old ugly race steel lugs,thats different,impact away

[OTHER SNAKE OWNER]

You are using the wrong tool...if you want to go cordless electric, you need the Milwaukee 1/2" M18 Fuel Impact (2763). I have the 3/8" version as well, and it does not come close to the power that the 1/2" unit has. I used the 1/2" to loosen the rear axle nuts, and those are torqued to 240 ft-lbs. It has absolutely no problems with lug nuts on any of my vehicles.

This ^^^^^

I have a Milwaukee M18V 1/2" drive (I cannot remember the model number, but I got it before the Fuel models came out. I think it is model number 2662-20, but the kit with the case, charger and extra Red battery) and it is rated to over 400ft lbs of torque (not sure exactly on the rating. But I know it was very high for a battery impact. I think the peak is at 450 ft lbs). Plenty for any lugs on any vehicle

[Viper Specialty]

I think you guys are having issues with overtorqued lugs. I have all of those Milwaukee tools myself, from the Hex Brushless to the the 3/8, to the 1/2 drive. They ALL will easily remove lug nuts- even the Hex Drive! Either you don't have the setting high enough, or someone over-torqued your lugs with a torque stick and an impact.

IMO, the 3/8 is the ideal tool for the lugs. The 1/2 drive will overtorque the install WAY too easily! The 3/8 or even the Hex on a moderate setting is perfect for quickly seating the lugs in prep for the torque wrench. On the 1/2, as soon as you get the "Ugga-Dugga"... its already too late.

For reference, I have:

Hex: 2757-20
3/8: 2758-20
1/2: 2763-20 [This thing is a monster... have yet to find something it cant remove]

Also FYI, there are a TON of tool versions from Milwaukee. I have no experience with the low-mid grade tools, but I am sure they are less powerful.

[ek1]

If you swap/rotate wheels/tires often, you shouldn't break the lug nut loose with an impact wrench this damages the lug nut and eventually the studs as well.
Same with when you put the lug nuts on, you don't tighten them as hard as you can with the impact wrench. Put them on by hand at least 4 full turns to prevent threads from getting stripped, then use the impact wrench to get them close to tight, then tighten with a lug wrench.

So assuming I don't give a shit about lug nut damage (I am actually going to switch to open-ended lug nuts soon), how much would it take to damage the studs if I loosen lug nuts with an impact wrench? Keep in mind, I NEVER use an impact wrench to tighten them (I always use a torque wrench).

[ForTehNguyen]

torque setting has to do with bolt tension and how much you need so it doesnt loosen, its a factor of the diameter of the stud. My 2015 mustang moved to 14mm studs up from 12mm of the last generation, it now requires 150 ft#. Same studs as an F250 and same bolt torque.

[ek1]

You are using the wrong tool...if you want to go cordless electric, you need the Milwaukee 1/2" M18 Fuel Impact (2763). I have the 3/8" version as well, and it does not come close to the power that the 1/2" unit has. I used the 1/2" to loosen the rear axle nuts, and those are torqued to 240 ft-lbs. It has absolutely no problems with lug nuts on any of my vehicles.

NO SHIT the 1/2" can undo the lug nuts! it's rated at 1,100 ft-lbs! So the reason I got the 3/8" is because its much smaller, lighter and and it takes less space in the Viper trunk when I go to the track. What I am trying to understand is why a tool rated at 210 ft-lbs cannot undo a lug nut torqued at 107 ft-lbs. If I have to go to 1/2", I will, but first I need to understand what is happening.

[ek1]

I agree 107 is of the chart tight. In all my years of various type of racing I have never seen wheel torque numbers this high. Right or wrong I won't do it.

So why do you think Dodge recommends this in the Viper manual?

lug nut torque.JPG

[Viper Specialty]

Guys, this isn't rocket surgery.

107 is completely normal for a 1/2-20 lug, and Vipers have always been in the 100 ballpark.

[bluesrt]

So assuming I don't give a shit about lug nut damage (I am actually going to switch to open-ended lug nuts soon), how much would it take to damage the studs if I loosen lug nuts with an impact wrench? Keep in mind, I NEVER use an impact wrench to tighten them (I always use a torque wrench).

you wont damage the studs

[SSGNRDZ_28]

ek1 - are you using anything on the studs? Antisieze etc? I know for my Teflon coated titanium lug nuts I only recommend ~80 ft lbs because any lubricant on the stud / nut requires less torque to achieve the same tension. So if you had something on the studs that is lubricating or reducing friction you are actually effectively tightening the nut with more force than recommended.

[ek1]

ek1 - are you using anything on the studs? Antisieze etc? I know for my Teflon coated titanium lug nuts I only recommend ~80 ft lbs because any lubricant on the stud / nut requires less torque to achieve the same tension. So if you had something on the studs that is lubricating or reducing friction you are actually effectively tightening the nut with more force than recommended.

Not using anything on the studs. I am contemplating switching to your lug nuts though.

[ForTehNguyen]

NO SHIT the 1/2" can undo the lug nuts! it's rated at 1,100 ft-lbs! So the reason I got the 3/8" is because its much smaller, lighter and and it takes less space in the Viper trunk when I go to the track. What I am trying to understand is why a tool rated at 210 ft-lbs cannot undo a lug nut torqued at 107 ft-lbs. If I have to go to 1/2", I will, but first I need to understand what is happening.

there is a max breakaway torque needed to start loosening the fastener. An impact gun does not apply a constant force, since its periodically impacting the anvil, the impact force has to be a lot greater than the constant force applied to the fastener from bolt tension. For instance the Dewalt 20V XR impact wrench is rated for max breakaway torque of 1200 ft# and a max torque of 700 ft#. When you use a breaker bar to loosen something you are applying a constant torque, not a hammering impact type of force. This isnt including any corrosion, heat/cool cycles that may add to the torque rating to break it loose.

http://www.dewalt.com/products/power...l-bare/dcf899b

[Arizona Vipers]

So why do you think Dodge recommends this in the Viper manual?

lug nut torque.JPG

For safety as 99% of the world doesn't check their lug nuts often. I do 85 ft/lbs, but I take my wheels on and off 3-4 times a weekend, bleeding, rotating sides etc. Never had one come loose.

[Dr.Ron]

I always use a breaker bar to loosen the lug nuts before using the cordless impact wrench to spin them off. This will make your lug nuts and your studs last much longer.

Same with when you put the lug nuts on, you don't tighten them as hard as you can with the impact wrench. Put them on by hand at least 4 full turns to prevent threads from getting stripped, then use the impact wrench to get them close to tight, then tighten with a lug wrench.

This is exactly what I do!

Ron

[ek1]

Just spoke to Milwaukee support. They told me that using an adapter (my socket is 1/2" so I am using a 1/2" to 3/8" adapter) eliminates 20% to 30% of the torque of the tool. They also said that the break-away torque of the tool is about 20% more than the rated torque (or 210 ft-lbs).

I'll buy a 3/8" 19mm socket in Home Depot today and will try again. If it does not work, the shit's going back.

[txA&M08]

I'll buy a 3/8" 19mm socket in Home Depot today and will try again. If it does not work, the shit's going back.

I know this isn't the purpose of the thread, but FWIW, I've had the Ingersoll Rand 20V since it came out 5ish years ago. It's an absolute monster and never skips a beat. https://www.amazon.com/Ingersoll-Ran...006GFQLE2?th=1

[Viper Specialty]

Just spoke to Milwaukee support. They told me that using an adapter (my socket is 1/2" so I am using a 1/2" to 3/8" adapter) eliminates 20% to 30% of the torque of the tool. They also said that the break-away torque of the tool is about 20% more than the rated torque (or 210 ft-lbs).

I'll buy a 3/8" 19mm socket in Home Depot today and will try again. If it does not work, the shit's going back.

Have you tried the obvious, which is breaking loose the lugs and making sure they are torqued correctly before blaming the impact?

Like I said more than once already in this thread, I have the same damn tools, and dont have your problem, on DOZENS of cars. The obvious answer, is that something is not right on your end. If you dont think you can have a wheel lug torqued to 200+ and still not be broken, think again!

[Arizona Vipers]

Have you tried the obvious, which is breaking loose the lugs and making sure they are torqued correctly before blaming the impact?

Like I said more than once already in this thread, I have the same damn tools, and dont have your problem, on DOZENS of cars. The obvious answer, is that something is not right on your end. If you dont think you can have a wheel lug torqued to 200+ and still not be broken, think again!

Maybe his battery is going bad and not putting out enough volts..