My department has 5 brush trucks most are ford f450's, all of them are duals. I would say it depends on the size of the skid unit, most of ours are in the 300-350 gallon range so the duals are needed because of the weight. We have never had a problem with the duals and i have never seen a brush rig around my area with single rear wheels so i have no idea if there are pros for single wheels.
Most departments around my area are purchasing F550 with duels on the back for new brush trucks. They are also getting either extended cabs or crew cabs. Most have custom built poly tanks, usually 400 gallons, and diesel pumps for the bed. They are proving to work extremely well in this area. Comfortable and does extremely well off road. We just purchased one last year and are very happy with it. I can't think of anyone that has had any problems with duels and going off road. Older brush trucks are just the single rear wheel but like I said everyone is purchasing newer brush trucks with the duels. Hope this helps a little bit. Good luck with your purchase. I will have pictures of our brush truck up on my page soon if you would like to look at it.
Ted I believe your looking for Firematic. They were first a truck dealer and in recent years designed and developed the B.R.A.T. for wildland and brush purposes. I have never had the chance to experience one but they look like good, capable trucks.
Weight on a tire is not much of an issue today, you can get a superwide or supersingle, single tire to carry the same amount. Singles are always better in the mud, duels tend to fill the space between them and once that happens, even with deep groves, the whole set becomes one big slick. This is easily seen in 4x4 and mud races, ever seen duels?? This will also take some research as you need to match the revolutions per mile front and back, I had convinced our trustees to do this on our new truck, a Navistar 7400 but could not match front to back. Look around, find a smart tire salesman, but keep in mind, this ain't going to be cheep.
1993 AM General
(M35A3 ESP 2 1/2 ton Cargo Truck)
400 gal Tank
225 gpm Hale Pump
Front Hydraulic PTO Winch
Central Tire Inflation System
400’ Wildland Hose (Pre-Connected)
400’ Wildland Hose (Dead Lays)
2-225’ Hose Reels
250’ 2 1/2” Supply Line
When our department got this brush truck, I thought it was too much. I take that back now. This truck has never failed us, can go anywhere, and lately has been used as a water rescue vehicle. It recently went through a flooded road that had water coming in the cab and had no problems. I suggest a 2 1/2 ton with superwides instead of duals.
Turning radius surprisingly pretty good. Truck is equipped with power assisted steering, CAT motor, allison automatic, and a central tire inflation system that will change tire pressure with the touch of a button to adjust for surface you are driving on. Our old duece had duals and manual steering and manual trans. It was difficult to manuver, but this new one is not bad at all.
Thanks to everyone for giving me your opinions. Personally I would like us to get an extended cab with duals, but there are a few guys who claim that duals get stuck too easily off road which I dont understand at all. The skid unit we have holds 250 gallons of water and will work on a 350 single, but I think it would be maxing it out.