Allow Volunteer Fire Departments nonrestrictive access military surplus including humvees, mk48's, and helicopters.

Volunteer Fire Departments are restricted from acquiring military hummers, MK48 transports, helicopters, 7 ton trucks, as they have been labeled unsafe for highway use.
If this is true, then why does the DOD allow police departments access to this same equipment for patrol use?
What the Volunteers are allowed to acquire, is worn out equipment from the 50s - 70s, that needs big money to make operational(m35, and m800 series trucks missing motors, cabs, transmissions, etc) than the departments can afford.
The other problem we run into is there is so much red tape, that from the time of initial contact, it takes up to 3 years to get a non-running scrap truck; then you have so many days to get it operational or they will take it away. Or we have to buy it outright for massive cost personally.