How to Weigh Your RV at a CAT Scale: The Complete Step-by-Step Guide
You have read the manuals, checked the door jamb sticker, and run the numbers through a calculator. But until you put your actual, loaded rig on a certified scale, you are guessing. A CAT Scale weigh is the single most important safety check every RV owner should perform—and it costs less than a tank of gas.
Why Weighing Your RV Is Non-Negotiable
Most RV owners significantly underestimate their actual loaded weight. Manufacturer "dry weight" or "unloaded vehicle weight" (UVW) numbers exclude propane, battery, water, cargo, passengers, and optional equipment. The difference between dry weight and actual loaded weight can easily be 1,500–2,500 lbs.
A CAT Scale weigh gives you three critical pieces of information that no calculator can estimate:
- Actual per-axle weights: Steer axle, drive axle, and trailer axle weights on a certified ticket.
- Actual tongue weight: Calculated by comparing drive axle weight with and without the trailer connected.
- Verification against all ratings:GVWR, GCWR, GAWR (front and rear), and trailer GVWR—all checked against real numbers, not estimates.
The uncomfortable truth
A 2023 RVIA survey found that over 50% of RVs on the road exceed at least one weight rating. The most common violation is exceeding payload capacity, followed by exceeding an individual axle rating. Both are invisible to the naked eye but catastrophic at highway speeds. A CAT Scale weigh is the only way to know for sure.
What Is a CAT Scale and Where Do You Find One?
CAT Scale is a network of certified truck scales located at over 2,000 truck stops across the United States and Canada. Each scale has three separate weighing platforms that give you individual axle weights—steer axle, drive axle, and trailer axle—all on one ticket. This per-axle breakdown is what makes CAT Scales dramatically more useful than a basic single-platform scale.
You can find a CAT Scale at most major truck stop chains:
- Love's Travel Stops—the most common CAT Scale host
- Pilot Flying J
- TA Travel Centers
- Petro Stopping Centers
- Independent truck stops across the US and Canada
Use the official locator at catscale.com/cat-scale-locator to find the nearest location. You can also download the Weigh My Truck app (iOS and Android) to pay and receive your ticket digitally without leaving your vehicle.
CAT Scale Pricing: What to Expect
CAT Scale pricing is straightforward and affordable. Here is the breakdown as of 2026:
| Service | Approximate Cost | Notes |
|---|---|---|
| First Weigh | $13.00–$15.00 | Pay at counter or via Weigh My Truck app |
| Re-Weigh (same day) | $3.00–$4.00 | Within 24 hours of first weigh; ideal for the second pass |
| Total for Two-Pass RV Weigh | $16.00–$19.00 | First weigh (truck+trailer) + re-weigh (truck only) |
For less than $20, you get a certified weight ticket with per-axle breakdown. Compare that to the cost of a blown tire on the highway, a transmission rebuild, or worse—it is the best safety investment you can make.
Step-by-Step: How to Weigh Your RV at a CAT Scale
The most useful RV weigh requires two passes: one with the trailer connected and one with the truck alone. This lets you calculate actual tongue weight. Here is the complete procedure:
Step 1: Prepare Your Rig
Load your RV exactly as you would for a trip: full fuel tank, passengers on board, cargo in place, fresh water at your typical level. The goal is to weigh in your heaviest realistic configuration. If you usually travel with empty tanks, weigh with empty tanks. If you boondock with full water, weigh full.
Step 2: First Pass—Truck + Trailer Connected
Pull onto the scale with your trailer connected. Position your steer axle (front wheels) on Platform 1, your drive axle (rear wheels) on Platform 2, and your trailer axle(s) on Platform 3. For a travel trailer, this is straightforward. For a fifth wheel, the trailer axles go on Platform 3 while the truck sits on Platforms 1 and 2. Press the call button, tell the weighmaster it is a private weigh, and wait for the horn or green light.
Step 3: Get Your First Ticket
Go inside and pay at the counter, or use the Weigh My Truck app for a digital ticket. Tell the cashier you will be back for a re-weigh. Your ticket will show three weights: steer axle, drive axle, and trailer axle, plus a gross combined weight. Keep this ticket—you will need it to compare.
Step 4: Second Pass—Truck Only
Find a safe place nearby to unhitch your trailer. Drop the trailer in a parking spot (most truck stops have room), then return to the scale with just your truck. Position your steer axle on Platform 1 and drive axle on Platform 2. Platform 3 will be empty. Tell the weighmaster this is your re-weigh. The re-weigh rate ($3–$4) applies.
Step 5: Calculate Your Numbers
With both tickets in hand, you can now calculate everything that matters. See the next section for a detailed walkthrough of how to read your tickets and extract tongue weight, GVWR compliance, and more.
How to Read Your CAT Scale Ticket
Your CAT Scale ticket has three weight values. Here is how to interpret them and calculate the key numbers:
Pass 1: Truck + Trailer (Connected)
Steer Axle: 3,420 lbs (Platform 1) Drive Axle: 3,880 lbs (Platform 2) Trailer Axle: 5,700 lbs (Platform 3) Gross: 13,000 lbs (Total combined weight)
Pass 2: Truck Only (No Trailer)
Steer Axle: 3,380 lbs (Platform 1) Drive Axle: 2,680 lbs (Platform 2) Trailer Axle: 0 lbs (Platform 3) Gross: 6,060 lbs (Total truck weight)
Key Calculations from Your Two Tickets
Tongue Weight:Drive Axle (Pass 1) − Drive Axle (Pass 2) = 3,880 − 2,680 = 1,200 lbs
Loaded Trailer Weight:Gross (Pass 1) − Gross (Pass 2) = 13,000 − 6,060 = 6,940 lbs
Tongue Weight Percentage:Tongue Weight ÷ Loaded Trailer Weight = 1,200 ÷ 6,940 = 17.3%
In this example, the tongue weight percentage is 17.3%—above the optimal 10–15% range for travel trailers. The owner should redistribute cargo to reduce tongue weight or check payload against this actual number.
What to Verify Against Your Weight Ratings
Once you have your actual weights, compare them against every rating on your vehicle and trailer:
| Check | Your Actual Weight | Rating to Compare | Source |
|---|---|---|---|
| Truck GVWR | Steer + Drive (Pass 1) | GVWR on door jamb | Yellow sticker |
| Front GAWR | Steer Axle (Pass 1) | GAWR Front | Door jamb sticker |
| Rear GAWR | Drive Axle (Pass 1) | GAWR Rear | Door jamb sticker |
| GCWR | Gross (Pass 1) | GCWR from towing guide | Manufacturer towing guide |
| Trailer GVWR | Trailer Axle + Tongue Weight | Trailer GVWR | Trailer VIN sticker |
| Payload | Truck Gross (Pass 1) − Curb Weight | Payload on door jamb | Yellow sticker |
Pro tip: Write your ratings on the back of your weigh ticket before heading to the scale. Having them ready makes the comparison instant. You can also use our Towing Capacity Calculator to pre-load your ratings and then plug in your actual CAT Scale numbers.
Common Mistakes When Weighing at a CAT Scale
Weighing with empty tanks
If you travel with water, weigh with water. A full fresh water tank can add 400–800 lbs. If you weigh empty and then travel full, your numbers are meaningless.
Skipping the second pass
A single weigh (truck + trailer) tells you combined weight but not tongue weight. Without the truck-only weigh, you cannot calculate actual tongue weight, which is critical for payload and stability.
Not having passengers on board
Your family and pets are part of the payload. Weigh with everyone in their normal seating positions. Four passengers can easily add 600–800 lbs.
Forgetting about the hitch
Your weight distribution hitch itself weighs 80–120 lbs and counts toward payload. Make sure it is installed for the first weigh if you use one.
Using the Weigh My Truck App
The Weigh My Truck app (free on iOS and Android) is the easiest way to use a CAT Scale. Instead of going inside the truck stop twice, you handle everything from your phone:
- Download the app and create a free account with your email and payment method.
- When you arrive at the scale, open the app and select the CAT Scale location (the app uses GPS to find nearby scales).
- Enter your truck or RV details (optional but helpful for record keeping).
- Press "Start Weigh." The weighmaster processes your weigh remotely.
- Your digital ticket appears in the app within seconds. You can download it as a PDF, email it, or save it to your phone.
- For the re-weigh, simply start a new weigh in the app at the same location. The re-weigh discount applies automatically.
The app stores your weigh history, making it easy to compare weights across trips and track changes over time. This is especially useful if you experiment with different cargo configurations.
Got Your CAT Scale Numbers?
Plug your actual axle weights into our calculators and verify every safety limit in under two minutes. Free, no sign-up.
Frequently Asked Questions
How much does it cost to weigh at a CAT Scale?
A single weigh at a CAT Scale typically costs $13-$15 (as of 2026). A re-weigh within 24 hours costs around $3-$4. If you need two passes (truck-only and truck-plus-trailer), budget about $16-$19 total. You can pay at the counter inside the truck stop or via the Weigh My Truck app. CAT Scale locations are found at most major truck stops including Love's, Pilot, Flying J, and TA Travel Centers.
Do I need an appointment to use a CAT Scale?
No appointment is needed. CAT Scales are first-come, first-served. However, avoid peak trucker hours (early morning and late afternoon) if possible. The scale is typically accessible 24/7 at major truck stops. Use the CAT Scale locator at catscale.com to find a scale near you, and call ahead to confirm the scale is operational if you are planning a special trip.
What is the difference between a CAT Scale weigh and a public scale?
CAT Scales provide per-axle weights (steer, drive, trailer) on a certified ticket, which is the gold standard for RV weighing. Public scales (like those at landfills or scrap yards) typically only give you a total weight, which is far less useful. Per-axle weights let you verify that no single axle is overloaded and let you calculate tongue weight by comparing drive axle weight with and without the trailer connected. CAT Scale also guarantees accuracy and will reimburse any overweight fine if their scale was incorrect.
Can I weigh my RV at a CAT Scale if I am not a trucker?
Yes, absolutely. CAT Scales serve all vehicles, not just commercial trucks. Many RV owners use CAT Scales regularly. Simply pull onto the scale like any other vehicle, press the call button to speak with the weighmaster, and tell them it is a private weigh. You do not need a DOT number or any special credentials. The weighmaster is used to RVers and will walk you through it if needed.
How often should I weigh my RV?
At a minimum, weigh your fully loaded rig once at the start of each camping season, especially if your cargo load changes from trip to trip. Ideally, weigh after any major change: new trailer, new tow vehicle, significant gear changes, or before a long cross-country trip. If you boondock or carry variable water loads, weigh with both full and empty tanks to understand your weight range. Regular weighing is cheap insurance against overload-related accidents and tire failures.
What do I do if my CAT Scale ticket shows I am over weight?
First, do not panic. Identify which limit you exceeded: GVWR (truck too heavy), GCWR (combined too heavy), GAWR (individual axle overloaded), or trailer GVWR. Then take action: remove unnecessary cargo, redistribute weight between axles, drain fresh/gray/black water tanks, or upgrade to a vehicle with higher ratings. Never drive knowingly overweight. Our calculators at rvtowingcalc.com can help you run what-if scenarios to find a safe configuration.
Related Guides
Sources & References
- CAT Scale Official Weighing Instructions — catscale.com
- CAT Scale Location Finder — catscale.com
- RV Industry Association (RVIA) — rvia.org
- How to Weigh Your RV Before a Trip — RV Life