Which engine do you have, 5.3 or 6.0? Either one will do. The 6.0 with the 4L80e will do a little better in the hills. My dry weight is 5800 and I don't travel with anything in the tanks. The 5.3 does pretty well for us. I'd rather have the 6.0 but not enough to spend the money. Never noticed or had any issues with the brakes on our 2000 Suburban. But, I will replace them when they start looking worn because it's an easy job and rockauto makes it a cheap job. We just got back from a trip to the mountains and had an awesome time. It was a little slow going up Black Mountain but, I didn't want to beat on the old girl so I ran 45 MPH up the mountain. We're old and peaceful so the speed limit or there abouts is perfect. The 1/2 ton burb with the 5.3 does fine. I added an additional transmission cooler and the 4L60e loves it.
Nevertheless, the big GM SUVs do fine. There's only one issue that I have found and that's the rear ends. I had mine rebuilt last year. If you're doing a lot of towing service that differential with synthetic fluids and be sure to put in what GM recommends as far as amount. It's a super easy DIY job. Some people say fill it till the oil runs out of the filler hole. Well, that's sorta true. If you're filling from empty and what you're putting in is roughly 2.1 - 2.5 no more quarts then do that. If filling from empty you'll notice that it will start pouring out of the fill hole. Then if you drive it and check again the level will be down because some of that oil has been drawn into the axle shafts and various parts of the rear end. The actual level is supposed to be down from the fill hole not right at it. I made a differential dip stick from an electrical tie. Look up the exact refill amount for your vehicle. I check mine before every trip and change the fluid about once a year. That overhaul was spendy. Overfilling can easily cause it to weep and leak at the axle seals and/or pinion gear seal. When it weeps at the axle seal the parking brake becomes oil soaked and useless. I keep my level around 5/8 to an inch down from the fill hole.
Also, get yourself some Sumo SuperSprings for that rear end. Best towing money that I have spent on the burb and an easy install too.
