I looked through old posts, but I thought I'd get some fresh advice.  My pressure washing company has operated out of 2 vans with water tank trailers and a F450 box truck for years.  I crammed a twin pump on to one of my trailers for the past few years.  I now have a SWS skid, currently in a trailer.  I am looking for a truck.

I know lots of guys go with 3/4 ton, but what is really the most economical in the long run, 1/2 or 3/4, diesel or gasser?  HD is always more expensive come repair time, 1/2 ton with air bags would seem to work.  Diesel is expensive, motor runs longer, but is more expensive to repair.  1/2 ton is cheaper all around for initial buy and repair.

Any advice would be helpful, especially from those who have had both.  I probably drive 25+ miles for most jobs on highway or county roads.  Service truck only, not for personal or sales.  I don't NEED to tow, but a 1/2 ton would do any that I absolutely had to.

Eventually, when I convert to all or almost all trucks, I would want I 3/4 ton in the stable for my commercial PW trailer.  I want to get rid of the 450 and use a trailer for the 2 hot water skids and water tank that it has on it, it's old and a money pit.