Last Changed 8/26/2010
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One thing to do when you get your RV and anytime there is significant changes to it or what you are carrying, is to have it
weighed. Only when you know your RV weight do you know if your tires are adequate and at the proper pressure.
The only effective weighing of your RV is when each wheel, or dual wheel pair, is measured separately.
Weigh-It is a couple who show up at numerous RV Rallies and Shows and will weigh your rig in
this manner. RVSEF (RV Safety Education Foundation) is another group that will also weigh
your rig in this manner. And now Escapees has started a weighing service,
Escapees SmartWeigh, that will be at Escapees
rallies. It would be great if more "per wheel" weighing outfits were around.
If you go to a certified truck scale, the best you can get is a "per axle" weight because the certified truck scale is designed
(usually with curbs) to keep the trucker from running a set of wheels off of the scale. Using a moving companies scale may be
an option as those scales typically don't have the curb constraints. However, those scales usually have ramped aprons around
the scale plate. This negates one of the elements of a proper "per wheel" weighing of having the vehicle level and in the
case of the trailer, the whole rig level.
The "per wheel" weighing outfits will start with a level spot. Then they use the
portable scales like the DOT officers use on random
stops. if your have more wheels than they have scales, they will put spacer boards under the wheels that don't have scales under
them. This insures you are getting the correct "per wheel" weight and not one biased by tilted loading.
This is why it is critical for a trailer to be pulled level. We see too many fifth-wheel trailers being pulled by pickups with
the pin set too high. This underloads the front trailer axle and overloads the rear axle. This condition will be very evident in
a "per wheel" weighing. At truck scales, this condition would be
camouflaged by the fact that the trailer axles will be weighed as a group
with the light front axle and the heavy rear axle.
When we had our motorhome weighed, the front axle was within limits, but we had all the tools located in a front left compartment, the left
front tire was just over limit. We moved the tools and balanced the loading. This is why a per-wheel weighing is necessary.
Below was the results when we had our rig weighed at RV Life on Wheels in Moscow Idaho. First
Red Rover was weighed and then the whole rig was weighed.
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| RVSEF Results |
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| Truck Alone |
You will note that
the rig is not symmetrical in weight along its length.
An assumption that you can just take the trailer axle weight
and divide by 6 to get tire loading would be incorrect.
(17,825 / 6 = 2,936) because we have one wheel with a 3,250
lb. loading.
An E Load Range tire would be fine for the average 2,936 but
would be overstressed in the 3,250 pound position. A G
Load Range tire is needed for that position, and since all
the tires should be the same, all the tires need to be G
Load Range
which is what we have.
Ideally we should try to balance the trailer by shift
loads. Unfortunately for us, the imbalance is due to the
weight of the three slides on the left side of the trailer
including the refrigerator, with only one slide on the right
side. There is not much we can do to achieve balance.
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Left |
Right |
Axle |
| Front |
5,500 |
5,250 |
10,750 |
| Rear |
4,425 |
4,175 |
8,600 |
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Gross Truck Axle Weight |
19,350 |
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| Truck with Trailer |
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Left |
Right |
Axle |
| Front |
5,100 |
4,900 |
10,000 |
| Rear |
7,275 |
6,800 |
14,075 |
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Gross Truck Axle Weight |
24,075 |
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| Trailer |
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Left |
Right |
Axle |
| Front |
2,975 |
2,900 |
5,875 |
| Center |
3,250 |
2,725 |
5,975 |
| Rear |
3,175 |
2,800 |
5,975 |
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Gross Trailer Axle Weight |
17,825 |
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Trailer Pin Weight |
4,725 |
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Gross Trailer Weight |
22,550 |
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