Support — Axle Load Calculator

Answers to common questions about Axle Load Calculator. If you need help, write to us.

Contact support

Email us at [email protected]. We usually reply within 1–2 business days.

Frequently asked questions

  • How do I set up the geometry?

    Enter the distance from the kingpin (5th wheel) to the center of the trailer's tandem axle group, and the tractor wheelbase. These two values let the calculator model how weight shifts when you slide the tandems or the 5th wheel.

  • Why can the prediction differ from actual scale weights?

    The result is a physics-based estimate. Real weights depend on the exact suspension, load distribution, 5th-wheel position, fuel, and many small factors, so the prediction may differ from a certified scale reading.

  • What should I do if I'm over an axle limit and sliding doesn't help?

    First re-check the geometry and weights you entered. If sliding the tandems or the 5th wheel still can't bring every axle under its limit, you likely need to reposition or remove cargo. Do not drive overweight — adjust or split the load.

  • How do I restore my Pro purchase on a new phone?

    Open the app on the new phone, go to the Pro screen, and tap Restore Purchase. The store restores your purchase when you use the same store account. If it doesn't work, write to us.

  • How do I get a refund?

    Purchases are handled by the app store (Google Play or the App Store). Request a refund through your purchase history in the store. As the developer we don't receive or process payments, so we can't issue refunds directly.

  • Which weight limits does the calculator use?

    The calculator uses federal US limits (up to 80,000 lb gross, 12,000 lb steer, 34,000 lb tandem drive, 34,000 lb trailer tandem, and the bridge formula), plus Canadian and state-specific limits where applicable. Always confirm the limits for the state or province you're driving in.

Important note

The calculation is an estimate for planning and does not replace a certified scale. After sliding the tandems or 5th wheel, re-weigh on a certified scale to confirm compliance. The driver is responsible for operating within legal weight limits.

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