Some big shiny new rigs come with as little as 600 pounds of extra CCC (cargo carrying capacity) That's certainly not a responsible manufacturer in my mind, but they keep on selling. Many people don't recognize that they are overweight (the rig, not them personally) and using the "maximum inflation" embossed on the side of their tires they just keep on moving down the road, wondering why so many people have blowouts. Eventually this leads to other problems. Cracked frames have been a problem in the past. Additions of overload springs, spring helpers, air bags in the springs, new springs, etc are common. Cracks, bulges and separations can be caused by movement where there wasn't designed to be movement. Abnormal brake wear, bearing failures, steering problems, etc. are all common.
So what is the solution? Awareness is a big part. Before buying a rig check the weight, decide what you'll carry and then determine if that rig is suited for what you intend to do. Think about your short term usage and your long term plans. I cringe every time someone says to just buy a rig that will do what you want it to do now and then buy something else later. For me, a guy who hates buying and selling, that's a waste of money, and effort. If you are taking weekend trips to a local campground 600 pounds of CCC may be adequate. If you are planning a 3 week dry camping trip to the backwoods I think you are overloading and don't have the correct rig.
How do full timers do it? Some do it by living a frugal life. One small tv (if any) a minimum of clothes, and trading books at the thrift store (used to be one of my favorite pastimes until Kindle) Others do it with tag axles. You are on the right track just by being aware of the problem and taking the steps you can to avoid problems.
Here are some things you can do:
Replace tires with a load range higher
Drive more conservatively, saving brakes and wear on suspension components
Buy consumables and food close to the campground instead of taking them the entire distance.
Travel with tanks closer to empty than full. Fuel tanks would take priority.
Refine the "needs" and make some things do double duty.
and my favorite, go commando every now and again saving on clothes space (if that doesn't generate comments nothing will)
Ken