What kind of an impact wrench to buy

I like working on these crawlers. I have two 1/2 inch air impact wrenches. They just don't seem to be strong enough to remove the larger bolts. don't know what the rating is on mine but I suspect 250. I am thinking about buying one with more power. What do you all use. what power rating would you recommend so what would you all recommend. All comments welcome. Thanks Norm in Missouri

A co-worker bought a MAC (maybe Ingersol Rand  built?) several years ago. It would twist off a half inch grade 8 bolt with no problem. Our shop air ran at 140 PSI and he never throttled it back. He did replace the hammer once after a couple years of abuse.
 If you work on bigger stuff, you NEED bigger toys. Maybe 3/4 drive impact sockets and a 3/4 drive hammer
 The shop spline drive impact would need an overhead hoist for me to be able to run it today.

You should consider a torque multiplying wrench. The type I prefer is a handle with a gearset built in. You power the gear set with your ratchet wrench. With the torque multiplier in one hand and your ratchet in the other you can apply massive leverage on the bolt. If I remember they were made in Mass. They were advertized in "Rock and Dirt" Typically they had 25 to one leverage. You can compound them by driving a torque multiplier with another torque multiplier.

There are other types of torque multipliers but this is the type I prefer.

PS You can really break impact sockets and big bolts using a torque multiplier.

Make sure, regardless of WHAT you do, that you have very low restriction in your air supply line. It takes pressure and volume to put the wrench in it's best performance zone... and don't think that just because a hose is big, that it flows well... I was using my wrench one day, and it started getting really weak... checked my compressor, and it was indicating just fine... figured there was something afoot with my wrench, so grabbed a different one, and it was a pooch too... then realized, checked hose for kinks (none found) switched to different hose, and bingo- worked great...

Problem was, that some spot INSIDE the hose, the hose liner had collapsed enough to restrict airflow.

Eventually, I cut the hose in half, put fittings on it, and checked to see which HALF flowed better... took the bad flowing half, cut it in half, and tested... eventually got down to the point where I had a six-foot section that wouldn't flow, the rest got made into short whips for other uses... that bad section I cut open for a look. Eventually the others will fail too, but they're still useful now.

I shouldn't pick on snap on tools, but when I used to work at an implement dealership, just about everyone had Ingersoll air impacts, cept for a new kid on the block, who had a snap on. One day this kid was taking something apart, and needed about four of us to help him. He had it down to one bolt holding it together, then rounded us up to help him. When he put his snap on impact wrench on this last bolt, it wouldn't budge it. One of the guys went and got his IR,and it zipped the bolt out like nothing, while we all laughed. That young man traded for an IR the very next chance he had. Otherwise, I like snap on tools, and I do think they have a better impact wrench now. Darrel

I have owned many 1/2 and 3/4" impacts. The IR's are hard to beat, a good value. My complaint with them is in cold weather the trigger freezes up and you cannot shut them down, LOL. In a shop not an Issue. Mac used to rebadge the IR guns but a few years back switched to AirCat composite guns, I have a 1/2 and a 3/4, these are animals. I use them most every day and run 150 PSI on my service truck @37cfm, and have never had any issues with them. If I remember correctly the 1/2 gun is around 750 ft lbs of torque, and the 3/4 is over 1K. I have removed many track pads from D8 & D9 dozers. Clean air, and daily oil is a MUST!. Northern Tool also sells AirCat guns and much cheaper than on the MAC truck. Torque multipliers are another story, at work we have a 55-1, it's 1/2 drive input and 1 1/2 output, I was tightening track frame bolts on a 1466 Koehring excavator years back and the 1 1/2 extension I was using let go, like a bomb went off, I was very lucky and was not hurt.

Lee

I got an older IR 2131 that's been good but I like bowhunters suggested 2135 model.Think mines only around 750 ft lbs.

I love SnapOn tools, except for there impacts they suck. MAC impacts are made by aircat which is an awesome impact