As a for instance... I used to tow a trailer/boat that totaled around 6500 lbs.

Started with a Jeep Cherokee - Solid axles, coils in front, leaf springs in rear... weighed around 4k lbs. Towed fine in a straight line but not good if I had to manueaver fast or stop fast. The brakes were by far the biggest issue, if the trailer brakes were to fail I would have been eff'd.
Moved to a Silverado crew cab - Solid rear axle, leaf springs... weighed around 6k lbs. Towed fantastic. Couldn't have been happier.
Then had a 2000 Range Rover - Sold axles, air bags all corners... weighed around 5500 lbs. Towed amazing also. The Silverado probably was a little better, but not by much.
Now I have a F350 super crew - Sold axles, leaf springs... weighs almost 7k lbs. When people use the saying "I couldn't even tell I was towing anything" this is it. Unreal how nice it tows... I could go across the country towing a 12k lbs load and be fine... the other vehicles would have worn me out mentally and physically just because of the extra attention you need to pay while towing with them. Yeah, they were great for little jounts around the state... but anything more than a couple hours would have been too much.

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