  Earth's atmosphere, on the other hand, is mostly nitrogen (78%) and oxygen (21%) with 1% being a mix of hydrogen, carbon dioxide and others. So you can see that Mars has much less atmosphere than the Earth does and oxygen make a proportionally much smaller fraction of of what there is than what we have on Earth.
Pickup trucks come in different shapes and sizes, and their weight entirely depends on the make and model. On average, a common pickup truck can weigh up to 3 tons, equivalent to 6,000 pounds.
Re: How much does your truck weigh? I did the same thing a couple of weeks ago--dropped some scrap metal off at the recyclers--mine weighed about 4050 pounds with my 160 pound ass in it and less than 1/4 tank of gas. About what i figured it would be.