Liquid Surge Control, LLC · SurgeBusters.us
How Hard Is It To
Really Stop A Tank Truck?
The Difference Between Road Conditions, Surge Energy and Accident Severity
Enter your rig, your liquid, and your road conditions. The calculator shows peak braking demand
at every fill level — at 40, 55, and 70 mph — and compares it against your legal GVW limit.
No sign-up. No gate. Results are instant. Physics from the Budwig surge force study,
University of Idaho, 2004. Confirmed by 10 institutions across 6 countries.
96.7%
Surge force eliminated
with Surge Busters®
with Surge Busters®
52.5%
Fill level where
surge peaks
surge peaks
⚡ Results update instantly as you type
📊 Two charts — without and with Surge Busters®
📧 Email yourself a copy — optional
Vehicle & Tank
Combined Empty Wt (lbs)
tractor+trailer or truck only
tractor+trailer or truck only
Tank Capacity (gallons)
Total Axles, combination
Total Braked Axles
Brake Efficiency (auto)
100%
Liquid
Liquid Name
Liquid Density (lbs/gal)
Quick-select
► All yellow cells are inputs
Change any value to recalculate
Change any value to recalculate
Road Conditions
Road Surface
Coefficient of Friction (CoF)
GVW Limit Inputs
Tire Load Rating (lbs/tire)
Number of Tires (total)
Tire Limit (auto)
81,000
Manufacturer GVWR (lbs)
State GVW Limit (lbs)
LEGAL GVW LIMIT
→ Min of above
→ Min of above
80,000
Vehicle Examples
5-axle semi: 5 total, 5 braked = 100%
Pickup + brakeless tank: 4 total, 2 braked = 50%
Straight truck: 3 total, 3 braked = 100%
Pickup + brakeless tank: 4 total, 2 braked = 50%
Straight truck: 3 total, 3 braked = 100%
Common Densities
lbs/gal
Water=8.34 | Fuel Oil=7.10 | Diesel=7.09
Gas=6.15 | DEF=9.07 | UAN 32%=11.06
UCO≈7.55 | Brine≈8.55
Water=8.34 | Fuel Oil=7.10 | Diesel=7.09
Gas=6.15 | DEF=9.07 | UAN 32%=11.06
UCO≈7.55 | Brine≈8.55
CoF Reference
Dry Asphalt=0.80 | Wet Asphalt=0.60
Gravel=0.45 | Packed Snow=0.30 | Ice=0.10–0.20
Three speeds (40/55/70 mph) always shown.
Gravel=0.45 | Packed Snow=0.30 | Ice=0.10–0.20
Three speeds (40/55/70 mph) always shown.
Tire Rating
Stamped on sidewall. Super singles and duals both work. Rating per tire × total tires = tire limit.
⚠ Worst-Case Summary: 52.5% Fill
Water, 70 mph / Wet Asphalt
Legal GVW
—
Braking Cap
—
Surge Force
—
Total Force
—
Multiple of Legal GVW
—
With SB® Total
—
No sign-up required. Results open instantly.
Step 1: Vehicle & Tank
Combined Empty Weight
Enter the total empty weight of the entire vehicle (tractor plus trailer together, or just the truck if it is a straight truck). Do not include the liquid load.
More tires raise your legal weight limit but do NOT increase stopping power unless those axles have functioning brakes.
Step 2: Liquid
Density drives everything
Enter the liquid name and density in lbs/gal. Density determines the K factor, which scales surge force directly.
Water=8.34 | Fuel Oil No. 2=7.10 | Diesel=7.09 | Gasoline=6.15
DEF=9.07 | UAN Fertilizer 32%=11.06 | UCO≈7.55 | Brine≈8.55
DEF=9.07 | UAN Fertilizer 32%=11.06 | UCO≈7.55 | Brine≈8.55
Anhydrous ammonia and propane are pressurized tanks. This calculator does not apply to pressurized vessels.
Step 3: Road Conditions
CoF: What it means and why it matters
Braking Capacity = Total GVW × CoF × (Braked Axles ÷ Total Axles)
Critical insight: Surge force is completely independent of road surface. CoF only affects braking capacity. On wet or icy roads, braking capacity drops while surge force stays exactly the same, widening the gap.
The Surge Formula
Surge Force = K × 47,000 lbs × fill × (1 − fill) ÷ 0.20 × (speed ÷ 40)²
K = 3.598 × (liquid density ÷ 7.10)
K = 3.598 × (liquid density ÷ 7.10)
Surge Busters®
96.7% of surge force eliminated at every fill level
With Surge Busters® installed, surge force is multiplied by 0.033, a 96.7% reduction validated by Dr. R.S. Budwig at the University of Idaho, 2004.
Surge force is independent of road surface. The surge curves do not change when CoF changes. Only the Braking Capacity line responds to CoF.
WITHOUT Surge Busters®
Peak Braking Demand, Water
Braking Capacity
Total @40 mph
Total @55 mph
Total @70 mph
Legal GVW
WITH Surge Busters® Installed: 96.7% of Surge Force Eliminated
Peak Braking Demand With Surge Busters®, Water
Braking Capacity
Total @40 mph
Total @55 mph
Total @70 mph
Legal GVW
Fill Level Data, Without Surge Busters®
Braking Demand by Fill Level, Water
| Fill | GVW (lbs) | Brk Cap | 40 mph | 55 mph | 70 mph | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Surge | Total | Mult | Surge | Total | Mult | Surge | Total | Mult | |||
Surge = K × 47,000 lbs × fill × (1−fill) ÷ 0.20 × (speed÷40)² · K = 3.598 × (density ÷ 7.10) · Budwig, University of Idaho, 2004
Fill Level Data, With Surge Busters® (96.7% surge reduction)
Braking Demand With Surge Busters®, Water
| Fill | GVW (lbs) | Brk Cap | 40 mph | 55 mph | 70 mph | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| SB Surge | SB Total | Mult | SB Surge | SB Total | Mult | SB Surge | SB Total | Mult | |||
With Surge Busters®: Surge × 0.033 (96.7% eliminated) · Budwig, University of Idaho, 2004 · US Patent No. 11,312,568
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Formula: Surge Force = K × 47,000 lbs × fill × (1 − fill) ÷ 0.20 × (speed ÷ 40)²
K values: 3.598 (Fuel Oil No. 2) · 4.226 (Water) · 5.605 (UAN Fertilizer) · K = 3.598 × (density ÷ 7.10)
With Surge Busters®: Surge × 0.033 (96.7% eliminated, Budwig, University of Idaho, 2004)
Source: Budwig, R.S. Surge Force Modeling Report. Dept. of Mechanical Engineering, University of Idaho, June 28, 2004.
Liquid Surge Control, LLC · surgebusters.us · liquidsurgecontrol.com · 866-787-4360
Results are theoretical models for planning purposes only. Applies to unpressurized or vented liquid tankers only. Anhydrous ammonia, propane, and LPG are outside scope.
Ready to eliminate 96.7% of surge force from your fleet?
Learn about Surge Busters® →
Questions about your numbers?
Gary@LiquidSurgeControl.com
· 866-787-4360