I think you are onto something about why an impact wrench won’t take off lug nuts, says Ed Y. I was having that problem, and decided that it was air flow. So I ordered a new Goodyear 3/8 hose.
I’ve also been reading that most shops use straight pressure on impact guns. I will try to hook the new hose up to the line before the regulator to get this impact to work. My compressor goes to around 145psi ish so I’m hoping that will do the trick. Now wish for warmer weather .

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Hey Willy, here’s how I decided to continue the compressor fix.
I did what you said. I took off the regulator completely. I bought a new goodyear 3/8 hose and hooked that directly to the tank. I then tried to take off lug nut and again no go.
BUT we both had the right idea.
Here’s what was wrong . I was using a 4 inch extension on the gun. I took off the extension and went with just the socket and VROOOM the lug nuts were flying off. I think there is to much play when I was using the extension and it was acting as a torque stick would.
To make sure this worked I replaced my 2 front shocks. The bottom 13/16 nut was rusted on there since 2003 and VROOM. No problem at all.
So for an impact gun full pressure works GREAT with no extension LOL But regulator is needed for like nail guns and cut off wheels ect. I got a pancake compressor for nail guns.
Thanks for the help, Ed Y.
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So glad that we (mostly you Ed) were able to get things working right and your impact wrench to actually take off wheel nuts etc.
Yes, the extension is acting as a sort of shock absorber, and instead of the impact from the wrench working on just the nut and the thread, the extension will torque and absorb some of the force. Removing the extension worked, so now, if you are planning a lot of work with the impact wrench, plumb the new, wrench feed through a higher flow regulator which doesn’t reduce the flow if it’s wide open, and try dialling the pressure down to just the point where it works. This will save air and the cost of compressing that air, and reduce the wear and tear on the impact wrench.
Though, of course, if you are only using the wrench incrementally, full flow seems to be the best way to go.