Quick and Dirty Calculator
for Truck Chassis greater than 14,000 GVWR

    Here is a simple calculator for estimating the water tank size that a medium duty truck can handle.  This is only an estimate!  It may help you choose a chassis.  It might give a starting point before doing more refined calculations.   Some things that will affect the accuracy of this calculation include:

  • the amount of stored items
  • the tank material.
  • the placement of the tank (will the load add too much weight to one of the axles?)
  • will the vehicle be used exclusively on good roads?

A more reliable tank capacity estimate is possible for these vehicles.  REC's Wildland Engine Calculator can be used for a more accurate estimate.  We suggest you look strongly at using the lower end of the range given unless you plan to use lightweight materials and minimize the number of stored items.

Remember to weigh the finished vehicle, fully loaded and ready for operation prior to putting it in service.  Make sure it does not exceed the manufacturers Gross Vehicle Weight Rating or the ratings for either axle.

Read the Guideline for Designing Wildland Fire Engines for the details.

Estimator for Medium Duty Truck Chassis

Enter the vehicle's GVWR as given by the lbs.
manufacturer.
Enter the weight of chassis or truck prior to lbs.
adding tank, pump and fire accessories.

Expect tank size to range from to
gallons of water.

Roscommon Equipment Center - Wildfire Equipment Research and Development