Every RV gains weight the longer you live in it, and the numbers on the brochure are not the numbers in your driveway. We put off weighing our Brinkley Model Z 3515 for months, and when we finally did it (in July 2025, after two months parked on full hookups), the process itself turned out to be easy. Everything around it was where the day got interesting. Here is the right way to do it, based on CAT Scale's own instructions, plus honest notes on where our first attempt went sideways.
Step 1: Find a CAT scale and load like you travel
CAT scales live at truck stops and travel centers, and the locator on the CAT Scale website shows every location. Any of them will work, but for an RV you want two things: a scale you can approach without tight turns, and somewhere nearby with enough room to unhitch, because you are going to cross the scale twice. Before you go, load the rig the way you actually travel: fuel full, gear aboard, and water at your normal travel level. We picked a travel center that was already on our route, which meant no extra miles and diesel while we were there.
Step 2: Position your axles on the platforms
A CAT scale is three platforms in a row, each weighing whatever sits on it, and CAT's instructions for a truck and trailer are specific: steer axle on platform 1, drive axle on platform 2, trailer axles on platform 3. Yellow lines mark the platform edges. Pull forward slowly, keep the rig straight, and creep up until each axle group is on its own platform. You get axle weights and a gross total; the scale cannot weigh individual corners. Nobody behind you expects speed here. Truckers do this every day and would rather you take an extra thirty seconds than get a useless ticket.
Step 3: Check in by intercom or the app
Once you are parked on the platforms, there are two ways to run the weigh. The traditional way is the intercom pole by the driver's window: push the button, give the cashier your information (say it is a first weigh and give a name for the ticket), then pull off, park, and collect the printed ticket at the fuel desk inside. The newer way is the Weigh My Truck app, which handles payment from the cab and sends the results straight to your phone. We used the app, and the axle weights showed up before we had even pulled off the scale. Either way, wait for the go-ahead before you move.
Step 4: Unhitch and weigh the truck alone
One pass tells you your total weight, but the numbers that matter most come from comparing two passes. So after the first weigh, we found a spot in the lot, unhitched the trailer, and ran the truck across the scale by itself. CAT's reweigh discount applies within 24 hours at the same scale, with your first ticket in hand: as we write this, a first weigh is $15.25 and a reweigh is $5.25. The fine print says a reweigh is for the same vehicle, and a truck without its trailer is technically a changed setup, so tell the attendant what you are doing and let them ring it up the right way. Fair warning: unhitching a fifth wheel in a travel center parking lot with trucks rolling past adds some pressure to a job you probably practice in calmer places. Take your time and run your normal checklist anyway.
Step 5: Read the ticket
Each ticket shows three numbers: steer axle, drive axle, and trailer axle weight, plus a gross total. From your two tickets you can answer the questions that actually matter. From our own tickets that day: 26,220 pounds gross on the hitched pass, 8,520 for the truck alone, which put the trailer at 17,700 pounds with 3,600 of it riding on the truck as pin weight, right at 20 percent of trailer weight and inside the healthy fifth wheel range.
- Gross combined weight: the total from the hitched pass. Compare it to your truck's GCWR.
- Pin weight: add the steer and drive axles from the hitched pass, then subtract the truck-alone total. The difference is what the trailer presses down on your hitch.
- Payload: the truck-alone total minus the truck's listed curb weight, plus that pin weight, is what your truck is really carrying. Compare it to the payload sticker in the door jamb.
- Trailer axles: check the third-platform number against your trailer's axle and tire ratings.
What we got wrong
Plenty, and it is all on camera. First, we let our hitching skills sit idle for two months, so the chocks were stubborn, the muscle memory was gone, and the morning took far longer than it should have. Second, we ignored the load-like-you-travel rule and crossed the scale carrying much more fresh water than we normally haul. Water weighs about 8.3 pounds per gallon, so we spent an evening at a Cracker Barrel doing subtraction to estimate our real travel weight instead of just reading it off the ticket. Third, we did not look at the slope of the lot before committing to it. The lot turned out to be one long subtle grade, and when we ran auto level, the system lifted the trailer wheels right off the ground, which is a special kind of panic in a 17,700 pound home (that is what the ticket said the trailer weighed that day, extra water and all). None of that is the scale's fault, but it is all part of weigh day when you are new at it.
You can watch our first weigh, panic included, in the travel day video post, and see us work through the actual numbers in the results video post. For the official word, CAT Scale publishes its own positioning instructions and a FAQ with current pricing and reweigh rules.
This guide describes how we did it on our own rig. We are not RV technicians, and this post may contain mistakes or steps that don't apply to your setup. Proceed at your own risk, and double-check anything safety-critical with a professional.