Slip-On Tank Engine Weight Calculator*
This calculator has been developed for the special case of mounting a slip-on unit into a pick-up truck cargo box.  Zeros must be entered into any entry box not used.  Letters in parenthesis refer to weights and distances shown in the graphical representation.

Click here to get a list of approximate weights of commonly used fire equipment items.

Manufacturer's Vehicle Weight Ratings

Enter the chassis's Gross Vehicle Weight Rating.(GVWR) lbs.
Enter the vehicle's Front Axle Weight Rating.(FAWR) lbs.
Enter the vehicle's Rear Axle Weight Rating.(RAWR) lbs.

Pick-Up Truck Weights and Wheelbase

Enter the total weight of the chassis prior to modifying. lbs.
Enter the weight on the rear axle. (Rcurb) lbs.
Enter the wheelbase. (wb) in. 

Behind the Front Axle
Enter the weight and horizontal distance from the front axle centerline to the item's center of gravity. For a graphical explanation click here.  Each item entered must be located behind the vehicle's front axle otherwise the calculation will not be correct.  Normally, this will be the case for the items listed below.  If your slip-on will be placed on a crew cab or if front mounted items like a winch or grill guard will be added, you will need to use our more complete calculator (click here).

Occupants:
       Enter the number of occupants and their distance       in.
       from the front axle. (H, h)
Water Tank:
       Enter the empty weight of the water tank and the lbs. in.
       tank CG distance from the front axle. (T, t)
Water Tank Capacity:
       Enter the water capacity of the tank in U.S. gallons gal. in.
       and the distance of the water's CG to the front axle. (W, w)
Hose Reel:
       Enter the weight of the hose reel, with lbs. in.
       hose, and distance from the front axle. (RL, rl)
Foam Proportioner:
       Enter the weight of the foam proportioner and lbs. in.
       distance from the front axle. (F, f)
Water Pump:
       Enter the weight of the pump and distance lbs. in.
       from the front axle. (P, p)
Storage Unit:
       Enter the weight of your stored items and lbs. in.
       distance from their CG to the front axle. (S, s)
Low Mount Slip-on Unit Extension Platform:
       If you have a low mount slip-on, add the weight and lbs. in.
      the distance from its CG to the front axle. (E, e)

 

Results

Front: Weight on axle lbs. % of FAWR % payload on axle
Rear: Weight on axle lbs. % of RAWR % payload on axle
Total: Total Weight lbs. % of GVWR lbs. of payload

 

* REC Project 61 discusses slip-on tanks in depth.  A version of the report is available on-line. It explains the use of this calculator.  The user is urged to read the report prior to using the calculator.