length to wheel base ratio

[Michigander]

I seem to recall a thread about 8 years ago concerning the best ratio for handling and I can not find it. Does anyone know the best length to wheel base ratio? Thanks!

[RLS7201]

barmcd wrote:

RLS7201 wrote:
Wheel base to over all length ratio is more forum/internet nonsense.
MY 95 Bounder has a ratio of .479 and it drives great! 190" wheel base, 33' long. Best thing is the turning. Then there is the diesel owners talking about rear over hang on the gassers. My gasser has a 13' over hang. Diesel pushers have a 12'+ over hang, depending on chassis. More forum/internet chatter. Bah Humbug!
You'll see folks telling how horrible or how great their rig drives, no matter the ratio or total length. No one can document the ratio thing.
If set up correctly, they all drive well.

Richard

It's called physics.

OK, any one can say a work. Can you detail what you said?

Richard

[SoCalDesertRid1]

I suppose a motorhome manufacturer can list it in whatever unconventional way they want. For commercial trucks, the standard is center of tandems, on a 3 axle tractor.

[Groover]

wolfe10 wrote:

Mile High wrote:

SoCalDesertRider wrote:

Mile High wrote:
So my wheelbase is listed as 279+tag. At 279 with 522 overall, I'm .534. Do I count the length to the tag?

Wheelbase of tandem axle chassis are measured from front axle to center of tandems (center of tandems is the midpoint between the first and second rear axles).

That doesn't seem to be how Winnebago lists it. I'm trying to find a diagram.

But, it DOES give a reasonable approximation of the handling impact of the tag axle configuration.

They may just use the distance from the front axle to the driven axle. This is somewhat valid if the tag axle can be unloaded for manuevering and you are trying to convince customers that your coach is not too cumbersome in tight spots. Changing the air pressure in the tag axles's air bags does effectively change the wheelbase.

[wolfe10]

Mile High wrote:

SoCalDesertRider wrote:

Mile High wrote:
So my wheelbase is listed as 279+tag. At 279 with 522 overall, I'm .534. Do I count the length to the tag?

Wheelbase of tandem axle chassis are measured from front axle to center of tandems (center of tandems is the midpoint between the first and second rear axles).

That doesn't seem to be how Winnebago lists it. I'm trying to find a diagram.

But, it DOES give a reasonable approximation of the handling impact of the tag axle configuration.

[Mile_High]

SoCalDesertRider wrote:

Mile High wrote:
So my wheelbase is listed as 279+tag. At 279 with 522 overall, I'm .534. Do I count the length to the tag?

Wheelbase of tandem axle chassis are measured from front axle to center of tandems (center of tandems is the midpoint between the first and second rear axles).

That doesn't seem to be how Winnebago lists it. I'm trying to find a diagram.

[SoCalDesertRid1]

If you tow something behind your motorhome, especially a trailer with heavy tongue weight, you want the rear axle to be as far back as possible.

I would not want a chassis where the wheelbase length was less than 2/3 (66 percent) of the overall chassis length. I would prefer it be around 3/4 (75 percent) of overall length.

[SoCalDesertRid1]

Mile High wrote:
So my wheelbase is listed as 279+tag. At 279 with 522 overall, I'm .534. Do I count the length to the tag?

Wheelbase of tandem axle chassis are measured from front axle to center of tandems (center of tandems is the midpoint between the first and second rear axles).

[Mile_High]

So my wheelbase is listed as 279+tag. At 279 with 522 overall, I'm .534. Do I count the length to the tag?

[hanko]

One of the reasons i chose the Allegro 36LA is because of the wheel base. 252 inches. works out to .566.

[resqguy]

The other thing to consider is if you tow or not. The force exerted on the back of the RV by your trailer or toad will be greater with a large over hang. The tail will try to wag the dog.

[timmac]

If your buying a newer gas class A I would not worry to much about the ratio, just compare the old gas class A from 20 years ago and you can see the ratio is far superior today with better heaver chassis and larger tires.

[Kayteg1]

I think lot of pickups are build with shorter wheel base for better turning radius, as most of them are buy as grocery getters.
I seldom could use my F450 flatbed carrying capacity as longer loads would raise front bumper to the sky.
It takes F550 to get axle past 50% of cargo area.
I did have problem with frame/body extended on Bounder by additional 6 feet and that what made me caution about such monkey job.
It "drove" fine... for a Bounder.

[wolfe10]

Mile High wrote:
Just curious, is the purpose of the smaller ratio just to keep maneuverability when those decisions are made at the factory, or do all coach makers just work around a chassis supplied by others?

Shorter wheelbase= less cost of chassis. Those extra feet of frame, lots of wires, air lines...... are not free. And, longer wheelbases often come with added GVWR which can mean larger tires, shocks, larger engine......

With today's much improved front wheel cut angles, the "short wheelbase is there for turning radius" doesn't hold a lot of validity.

[Mile_High]

Just curious, is the purpose of the smaller ratio just to keep maneuverability when those decisions are made at the factory, or do all coach makers just work around a chassis supplied by others?

[irishtom29]

When recently buying a new 34' gasser given a choice between units with a longer wheelbase (and/or a heavier chassis) for a given length and those with less I chose the unit with the longest wheelbase, and as it happened the heaviest chassis as well. I figure more of each can't hurt.