How to Weigh Your Motorhome

Don't overload your rig.

Many motorhomes end up overloaded simply because people put too many things into them. There is no quick and easy way to determine the weight of the items you have loaded, so there is a temptation to keep loading stuff until every available space is filled. People are loading by volume, but weight is far more important.

Unfortunately, you may have exceeded the load-carrying capacity of the tires or axles long before everything is stowed. The only way to tell if your motorhome is overloaded is to have it weighed.

Things You'll Need

• Public scales
• Worksheet to record and calculate weights

Instructions

1. Find a place to weigh your motorhome. There are probably several certified public scales in your area. You will find public access scales in a variety of places, such as moving and storage company lots, farm suppliers with grain elevators, gravel pits, recycling companies and large commercial truck stops. Most will charge a nominal fee.

2. Since your motorhome must be weighed when fully loaded, load it up with what you would normally travel with, including passengers, food, clothing, fuel, water, propane, supplies, etc. Any towed vehicle, such as a car, boat, or trailer, or items loaded on brackets on the back of the motorhome, such as bikes or motorcycles, should also be included in the weighing.

3. There are three types of scales: platform, segmented platform and single axle. The platform scale is long enough to weigh the complete vehicle. The segmented-platform scales provide individual axle weights and total vehicle weights simultaneously when the vehicle is positioned properly. Single-axle scales weigh one axle at a time.
   Since weighing your motorhome can be a bit of a math challenge, refer to the Resources link to obtain a worksheet for recording scaled weights.

4. This step is for the platform type scales.

   Start by pulling onto the scale so that only the front axle is on the platform (with the end of the scale midway between the front and rear axles), and record the scaled weight.
   Next, pull forward until the entire motorhome is on the scale, and record the scaled weight. This is the gross vehicle weight as scaled.
   Now pull forward so that only the rear axle is on the scale (again with the edge of the scale midway between the front and rear axles), and record the scaled weight.
   Next, if the motorhome has a rear tag axle, pull forward so that only the tag (rear) axle remains on the scale, and record the scaled weight. If there is no towed vehicle, this weight will represent the actual weight on the tag axle. To determine the actual load on the rear axle, subtract this value from that of the recorded weight of the combined rear axles.
   Finally, if there is a towed vehicle, pull forward so only the towed vehicle remains to obtain the "towed vehicle only" weight. Record the scaled weight.

5. This step is for the segmented-platform type scales. This is a much simpler way of weighing your motorhome so if you can find a segmented scale, that is your best bet.

   Simply position the motorhome on the scales so that each axle is centered as much as possible on separate segments, and record the scaled weights. To obtain the gross vehicle weight, add all the segments weights together.

   If there is a towed vehicle, pull forward so only the towed vehicle remains on the scales. If there is enough room for both axles of the towed vehicle to be placed on a single segment, record the scaled weight of that segment. Otherwise, record the values for the segments the towed vehicle axles are on and add them together. This is the total towed vehicle weight.

6. This step is for the single-axle type scales.
   Place your front axle onto the scale and stop long enough to record the scaled weight. Pull the motorhome forward until the rear axle is on the scale and record the scaled weight. To obtain the gross vehicle weight, add the two axle weights together.

   If there is a towed vehicle, pull forward so only the towed vehicle remains on the scale. Record this weight.

7. Now that you have obtained all the axle weights, you still have a little more work to do. You also need to obtain individual wheel position weights.

   To obtain the individual wheel position weights, follow the appropriate steps for the type of scale you are using, but this time, use only one side of the scale. Record these weights.

8. To calculate the opposite side of the motorhome wheel position weights, subtract the individual side weights from the respective recorded axle weights.

9. To determine where your weights stand in relation to your motorhome specifications , find the motorhome weight capacities placard. Look at the GVWR (Gross Vehicle Weight Rating) number and compare it to the total vehicle weight recorded. If it the recorded weight is greater than the GVWR, the motorhome is overloaded and you must remove some items and weigh it again.

10. Find the GAWR (Gross Axle Weight Rating) for the front axle. Compare this number to the recorded weight for the front axle. If it the recorded weight is greater than the GAWR, the front axle is overloaded and you must either remove some items from the front of the motorhome, or move some items from the front to the rear and weigh again.

11. Find the GAWR for the rear axle. Compare this number to the recorded weight for the rear axle. If it the recorded weight is greater than the GAWR, the rear axle is overloaded and you must either remove some items from the rear of the motorhome, or move some items from the rear to the front.

12. If the front and rear axles are within manufacturer's specifications, one wheel on any axle may still be overloaded. Compare the side-to-side wheel position weights for each axle. Make sure each wheel position weight is as close to half of the total axle weight recorded as possible. If not, reposition some items.

Tips & Warnings

• If you are towing a boat, trailer, or other vehicle, it should be weighed and combined with the towing vehicle's GVW to ensure the total weight does not exceed the GCWR (Gross Combined Weight Rating). The tongue weight of the towed vehicle should also be considered as it contributes to the rear axle weight and could possibly overload the rear axle.

• Always determine correct tire inflation pressure based on actual loads on the tires. Use the tire maker's recommendations, which you will find in load and inflation tables from the manufacturer. Never use inflation pressures lower than those printed on the motorhome's placard.

• All tires on both ends of an axle must have the same inflation pressure. If the load on each axle end is so varied that different inflation pressures are recommended, use the higher pressure on both ends. Or, redistribute the load so that the same inflation pressure is recommended for both axle ends.

• If you have a travel trailer or fifth wheel, weighing it is similar to the steps outlined here. Refer to the workbook link in the Resources section. This workbook provides forms used when weighing these type of recreational vehicles.

• Individual wheel position weights must not exceed the maximum tire load capacity. Maximum tire load capacity can only be used with the maximum allowable psi as listed on the sidewall of the tire.

Resources

• Worksheet for weighing your motorhome
• RV Mods and How-to's