Weight Distribution

[SWharton]

I am not too sure how to ask this question.

 

I understand that the best ride with a motor home is to have certain percentage of weight on each axle. I can't find any documentation on this.

 

We are getting a 2015 Winnebago Vista Gas 36Y. Does anyone know the answer to this?

 

Also, does anyone know if sway bars are standard on the Winnebago?

[Kirk W]

I'm not sure where you would find that sort of information and in all of our years of travel in a gas powered motorhome I have not heard such figures. I can tell you that if you have a GM/Workhorse chassis they have air bags inside of front coil springs and it is very important to adjust the internal air pressure based upon the weight for best handling. The easy way of that is to simply adjust pressure to where it is level as long as you don't exceed the axle ratings.

 

With a Ford chassis the front axle tends to be rather stiff if it is too lightly loaded and that may well be what you are hearing. We lived in a Ford chassis motorhome and I discovered that not only do you want the front axle loaded more than most are when you get them, but the proper inflation pressure in the tires is also important to ride and handling. The key is to look at your axle weight ratings and try to get the front one fairly close to that rating. Most motorhomes have most of their storage to the rear and so it is very easy to overload the rear axle while the front is not hear capacity. I learned to put as much of our heavy load into the front bays as possible.

[horizon36]

Kirk's logic is sound. Bring the front axle as close to the GAWR as possible without going over. Be sure to weigh your coach, on each wheel, once it's loaded to make sure you are balanced and in spec. The proper tire inflation can then be determined and that will result in the best handling and ride your chassis is capable of.

[SWharton]

Thanks. We are well experienced on the 5th wheel side with weight, tire pressure etc. but the MH side is a new ball game. I feel like a newbie but I am not a newbie.

 

I am sure after our first trip we will be well experienced. I had read someplace that the front axle should have at least 75% of the weight.

 

When we get the MH home we will be going over to the concrete plant to get each axle weighed and the entire motor home. Once we get to Sumter Oaks in the fall we will do a Smart Weigh.

 

Thanks all.

[Kirk W]

I am sure after our first trip we will be well experienced. I had read someplace that the front axle should have at least 75% of the weight.

 

Don't you mean 25% on the front axle? Typical axle ratings are 7000/8000# front and 13500/15000# rear. Going by axle ratings you need about 1/3 of the total on the front axle. The issue with gasoline chassis is that the cab area has very little storage space so adding weight on the front axle alone is almost impossible. The F53 chassis is leaf spring and tends to need added weight to improve ride. We found that going by the inflation charts for our tires based upon actual axle weights made a big improvement in ride and also in tire wear.

[SWharton]

I think we are talking about the same thing, just approaching the weight differently. If front is rated at 8000#, it should be loaded so that at least 6000# is on the front. More is better.

[Kirk W]

OK, meaning 75% of the axle rating......... That is probably a pretty good figure, but I'd try to get higher than that. I was quite surprised how much excess capacity we had on our front axle. By moving all of the heaviest things in our storage bays to the front bays and putting the things weighing least in the bays behind the rear axle, that made a big difference, but it did mean a lot of rearranging. I used the bay at the very rear for carrying our blue-boy tank and things like that which had very little weight. We were always very close to the max. for the rear axle while I never got to more than about 90% on the front. I even made some storage boxes for things like the hydraulic jack and heaviest tools to mount on the frame rails behind the grill and still never got close to the maximum.

[Tireman9]

Interesting concept. Comming at the question from the tire standpoint the issue usually is too much weight on an axle or unbalanced loading side to side.

 

Unlike trailers where running the tire at its max pressure is the best policy, MH will usually be better off (fuel economy and fewer tire problems wise) by adjusting the side to side weight to be as near 50/50 as possible. I would then also try and have an equal % of the GAWR front & rear. That means if you can get 75% of the front GAWR on the front and on the rear also get 75% of the rear GAWR that would be a reasonable balance.

 

Once everything is as balanced as you can get and knowing the heavier end axle load for each axle you consult the Load/Inflation tables to learn the MINIMUM inflation needed for all tires on each axle based on the heaviest loaded end.. I suggest your Cold Inflation Pressure be the minimum inflation from the tables + 10%.

 

Your TPM warning pressure should be the minimum pressure needed based on heaviest load not your CIP. With a TPM that provides early warning (loss from the Hot Running Pressure) will give you extra advance notice if you get a leak.