Fit perfectly as it should. Install tip you'll need to jack up front of truck (3500HD) duramax so A-arms will hang down and open up Installation point. I also put antiseeze on nut and silicone spray where bumper hits a-arm.My Original units had completely deteriorated.First, I turned the front wheels to allow for access to the suspension without removing the tire/wheel combo. Access is from the rear - so turn the steering wheel hard right for left (driver's side in USA), and hard left for right side of the truck (passenger side in USA)Then with the rear wheels chocked, and proper safety equipment (glasses, etc), I used a compressed air blow gun to clean out the area around the nut (garden hose with water would also work). In my case, everything was a bit rusty, so I applied a small squirt of penetrating oil on the top of the nut around the threads and let it soak in for 10 min (I used Liquid Wrench)Then to remove the nut, I used a 3/8 Drive Ratchet, 10" "wobble" extension (craftsman Item # CMMT44287) and a regular depth 15mm Socket. This allowed easy access to the nut from above with the front wheel turned so that access was from "behind" the wheel. Slight off angle, so wobble on extension was needed - Flex socket would also work. Nut is not provided with the new item - so save the nut for re-use!The old unit just fell out, as mine was deteriorated.last to fit the new item in, had to jack up the vehicle like I would if I were changing the front tire, this allows the suspension to drop and allows enough room to get the new bumper in place. Only needed to jack up the vehicle enough to allow clearance - tire barley off the ground was more than enough.Install:Hold the new item in place - stud through the hole for the nut and there is a small alignment pin that goes though a small hole to properly align the item. Then install the nut that was taken off during removal of the old item. I used a piece of paper to wedge the nut in the socket and hold it in place.Torque the nut to to spec and make sure the alignment pin stays in the small hole, I don't know the exact torque - but I used the general spec of about 30 ft/lbs (the real spec is likely somewhere from 22 to 37 ft/lbs)Fit exactly like its supposed to.Genuine GM part. Replacing these made a big difference in ride and handling as my original 20 year old set had ground down to nothing. These bumpers loose material slowly over a long period of time, so it's not something that's instantly noticeable. If yours are more than five years old they're probably half gone.Replaced the 2 old rotten ones that came on the truck with these new ones almost a year ago , so far they’ve held up great and show no signs of wear ….Easy to install took me longer to get the old ones out due to light Michigan rust. Does not come with new nuts you do have to use the old ones which is a 15mm socket size on a 2005 2500HD. Now just to see how long they last is the true testEasy to install! Great fitGM exact part. Easy to install. Made lie the original part. I prefer original parts but will use OME parts. Felt for this part I wanted original. Good value I feel. Truck rides and handles better on rough roads now.Easy to install, fit perfectly!Great deal, 1/3 of the price from the stealership.Works perfect. 2004 Silverado 2500hd duramax.