This question pops up from time to time. ” Will my compressor remove wheel lug nuts ?”
The answer is wrapped up in a whole series of issues relating to the air compressor.
First thing to consider is the pressure coming from your air compressor.
Most DIY and smaller air compressors cut out in the 100-150 PSI range. That means that the pressure of the air in the tank when the compressor stops will be somewhere between 100 and 150 PSI.
Next, have a look at your impact wrench manual or on the information plate somewhere on your wrench. What does it show as the operating pressure?
What is displayed as the minimum operating pressure for the impact wrench? Odds are pretty good that number will be in the 80 – 100 PSI range, though more industrial wrenches may show a higher operating pressure.
The thing is, as long as your air compressor has pressure in the tank that is equal to or higher than the minimum operating pressure of the impact wrench, then your compressor has the pressure to run the wrench.
But… and there’s always a but, isn’t there? 🙂
There is one other factor that is critical to determine ” will my compressor remove wheel lug nuts? “
Compressed Air Demand
Have a look at the manual for the impact wrench, or, at the plate on the handle. Does it show what the air demand of the wrench is? That number should be shown in CFM, which means Cubic Feet per Minute.
A small impact wrench may have a compressed air requirement of 2-4 CFM at 90 PSI for it to run properly. The compressed air demand for larger impact wrenches will be quite a bit higher.
Why is this important?
How Much Air Per HP?
The rule of thumb for air compressors is that they will produce around 3-4 CFM of compressed air at 90 PSI for each HP of motor size.
What is the HP of your compressor motor?
If you have a 2 HP motor on your air compressor the rule of thumb tells us that your air compressor is capable of producing 4-8 CFM of compressed air supply at 90 PSI.
Compressor Output & Your impact Wrench
If your impact wrench has a minimum operating pressure of, say, 80 PSI and your compressor has 130 PSI of air in the tank, then you have lots of pressure to run that impact wrench.
If your air compressor has a production flow of 4-8 CFM and your wrench requires 4 CFM at 90 PSI to run properly, then you have the flow to run that impact wrench.
Will My Compressor Remove Wheel Lug Nuts?
In the example shown, your air compressor will have sufficient flow and sufficient power to drive the impact wrench, and it should have no problem removing the wheel lug nuts…
But… dang, here’s another but!
You have to ensure that the air supply to the wrench is not compromised by having a too small air line, or a too long air hose to the air tool. The pressure drop caused by a problem air line could take the supply volume and pressure available to the tool out of the sweet spot for that impact wrench, and then the impact wrench will not deliver the torque desired.
And, you have to be sure that the wrench you use has the torque necessary to turn off those wheel lug nuts.
If you are using a 1/4″ impact wrench on a 2″, rusted on lug nut, hmmm. we’d expect you might still have a problem.
Here’s more information on the subject of why an air impact wrench won’t remove lug nuts:
Now that’s a real answer.
Wondering in the following air wrench and compressor will work for getting lug nuts off of my truck? The air wrench is a Husky 1/2″ model with the following specs: SCFM: 4, Max PSI: 90, Max Torque: 300 ft lbs. The air compressor is a Husky 8 gal hotdog style with the following specs: Running HP: 1.8, Max PSI: 150, Air Delivery: 4.8 SCFM at 40 PSI & 3.7 SCFM at 90 PSI. So far, I haven’t had much luck with this combination except for airing tires and spraying dust and dirt out of my workshop. Sure would make it a lot easier to work on my truck if I could wrench the lug nuts on and off! I’m not sure I have the air compressor set to its optimal output, but wondering if I will just need different equipment? Thanks in advance!
I cannot comment on whether the specs of the impact wrench suggest sufficient strength for that wrench to remove your truck lug nuts, but I can say that I feel your compressor is not powerful enough for the job to run that wrench optimally.
It’s also my belief that the output of small compressors is somewhat theoretical, much like the mileage estimates for new trucks and cars. They might get that mileage in a factory lab with ideal conditions, but not in the real world. Same with CFM outputs of compressors as far as I’m concerned.
Good luck with a bigger compressor, that little one isn’t going to cut it.
Thanks for the response and that’s what I needed to know. I suspected that the compressor was most likely my issue since it wasn’t a very expensive one and didn’t seem to have enough output. Looks like I’ll need to get another one with more power.
You are welcome. And by “more power” that means higher HP and CFM.
Do you think i can use this for my lug nuts.?
Will this compressor supply the flow in CFM and the pressure in PSI that your air wrench requires? If so, then yes, if not, then no. We cannot tell because we have no idea what your air wrench requirements are, Robert. Sorry.
I have had a Craftsman 919.167.600 compressor for several years. It has never been able to remove lugnuts or really any bolt or nut removal. It’s 1.6 HP 26 gallon upright tank and 4.9 scfm at 90. It came with a hose and 3/8 impact. I tried several different size hoses and several tools. Nothing ever works. It appears that the air at the hose outlet is not strong enough.
Any ideas on restriction locations or things I might try? Seems weird that a small pancake compressor can work the guns, but not this thing…
Here is my real life experience with smaller air compressors and air tools. I was a mechanic for 22 years 20 years ago and am now retired. I have a 9 year old Ridgid dual tank 2.5 gallon, 2.7hp 150 psi compressor that produces 3.8 cfm. I own alot of snap-on air tools 1/2″, 3/8″, 1/4″ in both impacts & ratchets. Also a long noise snap-on 1/2″ drill, air hammer, wiz wheel, die grinder both stright and angle, etc. No battery stuff as I am old school except for a small 1/4″ drive Ridgid 12 volt battery impact, and drill driver I still use for interior repairs like removing dashes for evaporator/heater core or electrical issues, etc. Anyhow my small air compressor easily runs my 1/2″ impact gun for removing lug nuts on both cars and trucks. And my 3/8″ drive IM31 impact gun using swivel impact sockets with out extensions can remove case bolts on most front wheel drive manual and automatic transmissions. The 1/2″ gun can remove front brake calipers, upper and lower controll arms, struts and spring compressor tool, exhaust clamps etc, whether heavily rusted or not. I have the large snap-on 3/8 high torque air wratchet and can easily remove or install alternator bolts, front engine covers etc with no problems. The reality is if you have 150 psi going through an air tool designed to operate at 90 psi which most all are listed at your going to have more than enough initial burst of power to remove most any bolts up to 21 mm and even 32, 34 or 36 mm front CV joint axle nuts.
Even a small 1.2 gallon tank like the BOSTITCH producing 175 psi will remove most any lug nuts, etc. I knew a guy that used one of these for some field repairs on his heavy equipment. Someone will say your running too much air pressure through your tools and will damage them? The first shop I worked at in Rockville, Maryland back in 1982 always ran there dual 250 gallon tanks at 150 psi at the request of their technician’s, and every other shop I ever worked at involving 5 others did the same. My tools have lasted through many many years of daily heavy engine work, transmission removals tear downs rebuilds an re-installs and are still working no problems today nearing my 62 b-day in Sept 2021. These smaller compressors are not what anyone would choose for a professional application due to small tank size and recharge wait times, but most people who’s comments I have read don’t seem to be using them at that level. Most are more home owners trying to save themselves some money on attempting there own repairs and therefore unless there vehicles are constantly having problems requiring the use of air tools on a regular basis, really most likly don’t need a larger air compressor to make the few repairs to there vehicles that will occur. Bigger when it comes to mechanics equipment is not always better, it’s just bigger and takes up more room in most peoples limited 1 car garage. Down sizing is just that, smaller well thought out equipment that can do the same things only on a smaller scale.
Using a 3/8 impact is not going to loosen lug nuts. 1/2 inch minimum is needed at at least 140 psi depending on how how much torque your wrench puts out in reverse.
Great answer just what I was looking for , thank you!
Compressed air is compressed air, regardless of the source. If you have air at 120 PSI, whether it is in a tank on a pancake compressor, or in a 30 gallon upright compressor tank, 120 PSI is 120 PSI – meaning that the air will impart the same force in the air tool. If your impact wrench, using the air supply, cannot loosen a lug nut, then it’s either two things. The lug nut itself has rust-frozen on to the point where the force needed to break it loose exceeds the force available from your impact wrench, or, the air supply to the impact wrench cannot provide enough flow at that 120 PSI (or whatever the pressure required by your wrench) to power the wrench properly. If you find the manual for the impact wrench (or look on line for it) it should tell you what the operating pressure of the wrench is, AND THE FLOW REQUIRED! If your compressor cannot provide the flow provided at the pressure indicated, then that’s likely the problem. If, on the other hand, the compressor provides the pressure and flow that the impact wrench requires to work properly, then the wrench itself is not powerful enough to break the lug nut free.