There are a lot of components on these armored vehicles that wear out when used, especially the engines, air conditioning and electronics. It's for this reason that many army's have long used heavy tractor trailers to haul tanks and other armored vehicles to the battle zone. This was a lot cheaper than letting the vehicles rumble along on their own.
Aircraft are even more expensive to operate, although their unit of measure is the hour. Most warplanes cost $3,000-$5,000 an hour to run. But given the high speed they operate at, their cost per kilometer traveled is only $5-$10. Helicopters are a different story, as they will spend some time just hovering. But they are expensive as well, with it costing about $3,200 an hour to keep an AH-64 Apache gunship in the air, and about half that for an UH-60 Black Hawk transport. A tank, if moving most of the time, is only going to average about twenty kilometers an hour, giving it an hourly operating cost of $6,000. So, in effect, it's more expensive to operate an M-1 tank than an F-16 fighter.
To keep the costs down, very realistic vehicle simulators are being used. These cost $3-5 an hour to operate and are becoming increasingly popular. But the need to operate so many armored vehicles every day in Iraq is one of the things driving the cost up.
It's more expensive to operate an M-1 tank than an F-16 fighter. Don't be surprised, as modern armored vehicles are very expensive to run, with an M-1 tank costing about $300 per kilometer travelled to operate, and an M-2 Bradley, some $100 per kilometer. This does not include ammunition used. In peace time, one of the biggest expense is the tracks. For a Bradley armored vehicle, it costs $18 per kilometer for the wear and tear on the tracks. A set of tracks only last about 1300 kilometers, after which they have to replaced with a new set costing $23,000. Normally, the tracks are only replaced once a year, giving the troops a "budget" of about a hundred kilometers a month for training on each vehicle. But in the advance on Baghdad, many Bradley's racked up over a thousand kilometers. Since then, the Bradley's have been used for patrolling, covering hundreds of kilometers a week.