CAT Scale Weighing Protocol: Steer, Drive & Trailer Tandems [2026]

1. How CAT Multi-Platform Scales Work

Certified Automated Truck (CAT) Scales are the gold standard for weight enforcement compliance in North American trucking. Operating at over 2,050 truck stop locations across the United States and Canada, these multi-platform scale decks allow a commercial tractor-trailer to weigh all axle groups simultaneously without uncoupling.

The scale deck consists of three independent electronic scale platforms separated by visible steel expansion joints:

2. Step-by-Step Weighing Procedure for Drivers

To obtain an accurate, legally certified scale reading, follow this standardized driving routine:

1. Position Axles on Distinct Pads: Pull forward slowly onto the scale. Check your side mirrors to ensure your steer tires rest fully on Platform 1, your drive tires rest on Platform 2, and your trailer tandem tires rest on Platform 3. Never allow a tire to bridge across the steel separation seam between pads!
2. Set Parking Brakes & Idle: Set your tractor parking brake, leave the engine idling smoothly, and keep your foot off the service brake pedal.
3. Reach the Driver Intercom: Push the call button on the high intercom pole positioned outside your driver window.
4. State Truck Information Clearly: When the fuel desk attendant responds, provide your Company Name, Tractor Number, and Trailer Number. Confirm if this is a "First Weigh" or a "Re-Weigh."
5. Proceed to Fuel Island Parking: Once the attendant says "You're all set, come on in," pull your rig completely off the scale and park in a designated staging space.

3. How to Read & Verify a CAT Scale Ticket

When you pick up the yellow certified scale ticket inside the fuel desk, immediately perform the 4-Point Compliance Check before returning to the highway:

Action Required: In the example above, even though the total gross weight (79,120 lbs) is legal, the drive axle at 34,420 lbs will trigger an immediate fine at the next state weigh station! The driver must slide the trailer tandems forward 2 holes to shift ~500 lbs off the drives onto the trailer tandems.

4. The $3.00 Re-Weigh Protocol (After Sliding Tandems)

CAT Scale understands that professional commercial drivers often need to adjust slider pins or 5th wheels after scaling:

• First Weigh Fee: Typically $13.00 to $14.50 depending on location.
• Re-Weigh Fee: Only $3.00 to $4.00.
• Re-Weigh Eligibility Rules: You must return to the exact same scale location within 24 hours using the same tractor and trailer combination, presenting the original ticket number to the attendant.

Spending $3.50 to re-verify an axle pin shift is the cheapest insurance in trucking—saving you from $250 to $1,500 state DOT fines and costly safety inspection points.

5. The CAT Scale Guarantee: What Happens If You Get Fined?

CAT Scale stands behind its electronic accuracy with the famous CAT Scale Guarantee:

6. Digital Scaling: The 'Weigh My Truck' Mobile App

Modern commercial fleets bypass the intercom pole and indoor fuel desk entirely using the free Weigh My Truck mobile app (iOS and Android) developed by CAT Scale:

1. Drive onto the scale pads; GPS automatically detects the truck stop location.
2. Confirm your truck/trailer number on your smartphone screen.
3. App bills your fleet card (Comdata, EFS, Fleet One) or credit card automatically.
4. Certified axle weights appear instantly on your phone screen and email a certified PDF ticket directly to your fleet safety and dispatch office.