[Acejam2k]

Hey all,

I've been thinking about picking up some air tools perhaps. Basically an impact wrench and a compressor with some sockets that I commonly use, for mainly car work.

I had one quick question though. I often see impact guns advertised as 300ft-lbs of torque, as an example. But how do you adjust the torque setting for an impact gun?

So if I want to torque my lug nuts to 75 lb-fts, but the gun is rated for 300, won't that over torque the wheels?

[Hitman83]

You really shouldn't use an impact gun on a part that needs to be torqued to a specific spec. There are attachments for the socket that slip at a certain torque but I've heard they aren't that reliable and often over torque the bolt. Unfortunately I have no first hand experience with them

[04srt4black]

I know on tha back of my Snap on 1/2" impact there are four diffrent levels . From 200-900 ft lbs . Not sure if this helps .

But i always used a tq wrench to tighten lugs and other things .

[05_GD7]

most impact guns can't adjust torque.....so 300 ft lbs is way too much.

You can either:
1) Use an air ratchet to put the lugs on - they rarely go above 30-40 ft lbs or so
2) Buy a cordless drill and use that to drive the nuts on

But either option requires you use a torque wrench afterwards to ensure the proper torque (always do this!!!)

[flatthump]

It's the PSI that dictates the amount of torque. There is no real way to adjust it accurately.

[jungo75]

In my auto shop we use torque sticks that you hook up to the air gun. They are by range and they won't torque more than ???lbs. each no matter how much torque the air gun has. They go by colors, red, yellow and green. After that you use the torque wrench. You can check with sears or mac tools to see if they have them.

[flytojungho]

yea, usually you use impact gun of some sort to drive the lugs on the wheel (since it's faster than by hand) and hand torque the lugs with tq wrench. Try not to use impact gun to tq the lugs because unless you have years of experience, it'll be hard to get the range of tq that you want with an impact gun

[SAx COLIN STi]

Also, remember that an impact gun's torque increases the longer it hammers no matter what the setting is you can sorta hear it, has a rythm to it. My IR Titanium 1/2" has four settings but it the lowest setting basically slows down that hammer action that for when you're trying not to break something taking it off. ie: Old rusty exhaust bolts.

I use torque sticks at work everyday but they're only 0% accurate they're always higher when I check em with a torque wrench.

But if time is not a factor just use the torque wrench, it's really easy to overtorque lugnuts with just an air gun. As for un-sensitive undercar work like suspension/steering and brake perches I just use the "really tight" guideline for torque specs.