From Roughly 2,600 to About 6,000 Gallons: Let the Route Set Your Bobtail's Tank Size

The Situation

Bobtail tank sizes run from about 2,600 to 6,000 gallons on 33,000-lb GVWR chassis from Kenworth, Peterbilt, International and Freightliner. None of those builders itemize the delivery package's weight on the spec sheet. Pull that number from your dealer quote before you calculate real deliverable gallons, and size the tank to your route terrain — mountainous areas need smaller tanks.

The Facts

Custom Truck One Source says a 500-gallon tank delivers 300 to 325 gallons per stop, while larger tanks deliver proportionally more — a tank around 1,000 gallons delivers 600 to 700 gallons. Which engine and hood configuration on Peterbilt's Model 537 pairs best with a given tank size is not yet confirmed in the manufacturer's own materials, so work that pairing out with the dealer before ordering.

Business Impact

When you order a new bobtail, whether your fleet runs three trucks or thirty, you work inside the same weight math. Every pound of steel tank and delivery hardware comes out of the weight budget a Class 7 chassis is allowed to carry. The pump, meter/register, hose reel, valves and remote shutdown all subtract from usable payload before you load a single gallon of propane. None of the builders itemize that package weight, so pull the number from the dealer quote before signing. What this means for your business: 1. Chassis choice sets the weight ceiling before tank size is even picked, so route and chassis specs need to happen together. 2. Delivery-package weight is a dealer-quote line item — ask for it in writing before comparing trucks.

Key Takeaways

• When you run mountainous or tight-turn routes, size down from the range's top end, since a smaller tank clears steep grades and narrow turning radii more easily than a larger one.
• Your bobtail's real deliverable gallons come from stops per route, not rated tank size — oversizing a tank for a short route just adds unnecessary weight and slower handling.
• Chassis weight rating and delivery-package weight need to be specced together, since both draw from the same GVWR ceiling before route capacity is even calculated.
• Test your candidate tank size against your toughest route before ordering to avoid paying for capacity the truck can't actually deliver there.

Action Steps

1. 1.Pull this week's route logs and compare mountain grades or tight turning radii against the roughly 2,600-to-about-6,000-gallon tank range, so you don't order tank capacity your route can't actually clear.
2. 2.Ask each builder's dealer for the delivery package's weight in writing before comparing GVWR numbers across chassis.
3. 3.Call Alliance Truck and Tank at 800-632-2038 this week to get chassis and tank size options across Kenworth, Peterbilt, International and Freightliner lines for your route.
4. 4.Confirm with your dealer which engine and hood configuration on your chosen chassis fits the tank size you're speccing, before signing a purchase order.

Competitive Advantage

When you spec tank size to actual route geography instead of maximum brochure capacity, you keep more deliverable gallons per truck and avoid buying a chassis that struggles on tight, hilly routes. That discipline shows up in stops completed per day.