I'm on a small volunteer department and we have a mini pumper that is a county truck so it response to grass fires and structure fire out side the city limits may question is to replace it with a new truck altogether or put 4x4 chassy cab under the old bed ? The pump and valves and tank are good . But the 1984 E700 chassy was not designed for off road use and is shaking at hiway speed.
What do you think for a department with limited cash?
Being on a small dept. myself, I would go with keeping the pump and tank and looking for a newer vehicle that would support the wight and meet the deptartment's needs.