The problem with just looking at weight tow rating is that it ignores cargo/load capacity of the truck. It is very easy to exceed cargo capacity with passengers, bed cargo and tongue/pin weight, in fact that is probably exceeded much more often that actual trailer tow weight. Add in 4WD and a diesel and you take real hits on load capacity. My old 4WD Crewmax Tundra has shit for load capacity: 1341lbs. I had a truck cap on it and carries a couple of hundred pounds of gear and tools most of the time in it which left a very capacity for trailer tongue weight. When we first looks at RVs, we had several sales slugs at dealerships tell us we would be fine towing a 27-28’ trailer with the Tundra. I see this on RV forums a lot where a newbie is told by a truck dealer and the camper dealer that their new 1/2 ton 4WD crew cab truck will be awesome to tow that new “1/2 ton towable” 30’ travel trailer that has a 9k gvwr. They then load the bed up with bikes, chairs, firewood and coolers and and then all the shit in the trailer and that 650lb dry, unloaded tongue weight becomes 1k+. Add Mom, Dad, the 3 kids and golden retriever and that half ton truck gets pushed all over the road on their first two trips and they are back the dealer buying a 3/4 ton.