I have two impact wrenches that are rated for a maximum pressure of 90 psi. I have to run both at 140-150 psi to get them to produce enough torque to remove and replace lug nuts. I've checked the lug nuts by hand with a short breaker bar and they're not overly tight after hitting them with either wrench at that psi. The same is true of my framing nailer. It too is rated for 90 psi but I run it at about 125 psi.

Am I missing something?

Dan,
Air tools get gummed up and need cleaning some times. They also need oil regularly. Beyond that I do not know. Pretty simple tools.

I'll answer my own question after doing some checking on the Web.

Air tools carry an operational pressure rating. For an impact wrench, this is the pressure on the tool when it's running at full speed with the control valve open. The air pressure being supplied by your compressor is going to drop significantly when you open the valve based on the setting of your pressure regulator. If you have your regulated pressure set at 90 psi with the tool valve closed, the pressure is going to drop well below that once you open the valve by pressing the trigger on your wrench. In order to get 90 psi going through your wrench with it running, you'll need more than 90 psi in your tank, and a higher regulated pressure setting as well. When I had the static, regulated pressure set to 90 psi, I was way off base.

So then, in order to set your wrench for maximum safe pressure, allow your compressor to reach a setting of 130 psi or more. Next, run your impact wrench wide open and adjust the regulated pressure valve to 90 psi. You'll find this pressure is much higher when the tool is not running. For example, the maximum tank pressure on my 6 gallon compressor is 150. It takes 140 psi of static, regulated pressure to maintain 90 psi of operating pressure on my impact wrench with it running wide open. I found these settings to be the same for both of my impact wrenches. Not sure but I suspect my framing nailer will operate perfectly at these same settings.

My Ridgid throws out 450ftlbs and it’s battery powered

That's lesson #2 if someone knows how - how to measure the torque produced by an impact wrench.

I have a basic torque wrench with a lever gauge. I wonder how accurate it would be to read the lever at the instant a lug nut breaks loose. If the lug nut were tightened with an impact wrench, the break free torque would roughly equal the applied torque, correct?

Air tool oil. Sounds like you need some from my experience.

Both tools are new and well oiled.

Both work great now that I'm getting the right and safe psi going through them.

Yes, got a little bored today.

"To be certain that you are getting 90 PSI of pressure when the tool is running; use an air regulator to gauge the pressure while the tool is wide open. If the needle reads 90 PSI when the throttle of the tool is closed, but dips below that when the tool is engaged; you need more pressure. Again, most air tools are designed to run at 90 PSI and will under-perform if under pressurized."

Get an in-line pressure gauge to measure the pressure at the tool it can be much less than the rated pressure at the compressor . If you have a 50 foot hose you'll probably have to turn the compressor pressure up at the regulator to 100 to 125 Psi to get 90 psi at the tool.

Thanks. That's good to know.

Supply line inside diameter can eat you air flow. Remember, sometimes a higher pressure is used to offset low flow.

I watched a lot of YouTube videos comparing the different battery powered torque wrenches. This one was 3rd, lost to the Milwaukee witch put out almost 1000ft lbs, and the Chicago Electric that put out almost 600. Could justify the Milwaukee price tag, and didn’t want a Chicago because I already have Ridgid batteries and charges.

It hasn’t let me down. Only needs 1 or 2 uggas to tighten lug nuts. 3-4 iggas and you’ll be breaking them loose because they will be over torqued

I always run my impacts, air ratchets and die grinders at 150psi, my air hammer I'm not sure, I just pinch it down with the needle valve to keep it from beating itself apart. If I don't run the impacts at 150psi I don't get the performance I expect. I run a 1/2" hose for the smaller tools, and a 1" hose for the spline and 1" impact. When I wrenched at a Cat dealer for a living, I just factored a 3/4", 1/2" and a 3/8" impact in each year as a cost of doing my job. The company supplied the spline drive impact, and it needed a rebuild about once a year. For years I made fun of the guys with the cordless tools. Now days for my tire changes and other light duty tasks, I wouldn't trade my Milwaukee Fuel 1/2" impact for any of them, that thing is very handy. I can change all 27 chisel points to sweeps on one battery with that Milwaukee and have some left, really nice tool. And, if you tighten a bolt or nut to 150 ft lbs, it will take more to break it loose.

Are you referring to the pressure shown on your regulator with the tool running wide open or at rest?

I use a Milwaukee M18 fuel impact 90% of the time. They are in a class of their own.

Check pressure at the tool with it wide open

I did not even think of volume and Line pressure. Makes sense. Glad you got it figured out.

I was just using my IR 231 impact today. I put my in-line gauge on just to see where the difference at the compressor. I set the regulator to 115 psi and I had exactly 90 psi at the tool running wide open . My hose mounted on my reel is a 3/8 x 50’. I have a 1/2” by 50 hose for my bigger impact wrenches.