IR231 heavy?? real tools have heavy bits my friend.
rated pressure is running pressure but 90% of the impacts wrenches are over hyped ratings. In theory...in a perfect world any gun rated at 200 lbs-ft would easily remove any lug nut, but in the real world 90% of the wrenches rated at 200lbs-ft can't manage 100 when actually tested. Plenty of videos on youtube showing the real numbers of many popular ones, including the IR2135 which comes up short. We've all discussed how cheap, low quality tools and homeowner tools often simply don't do the job...impacts are the same thing. homeowner models (craftsman, lowes, husky, ch, alltrade...) don't usually have the QC behind the manufacturing process to even compare to the model they rip off. I've used (and own) some that don't do what they are rated to do. Got a CH that is great for putting ON lug nuts since it can only manage about 125 even tho it's rated for 250. Meanwhile my plug in electric from HF can easily take off lug nuts that CH can't budge.
Also - watch the auction site - I got my 231h freshly rebuilt for the cost of the rebuild kit plus shipping. Under $35 to my door.