wheelbase

[bigford]

what is the right way to figure wheelbase?
axle nut of the steer to axle nut of the last axle
on my wrecker it is 25'' and when I scale up I get 29'2'' or 350''
im thinking I could go longer for the wrecker

[Cossett]

Thats the way I would work it out ctr front axle to ctr rear axle
As over all length would be front of the vehicle to rear of the vehicle

Cheers Tracy

[RCP57]

I could be wrong but I think it is measured from the front axle to the center on the tandems(trunion). That's the way it was measured on the 850 KW's anyway. I thought it was measured from the front to rearmost axle and had to redo my frame length twice because it was too short!lol

[TRUCKMAKER]

Reg is correct, steer axle center line to rear suspension centerline.

[bigford]

so the rear leaf spring pivot nut

[TRUCKMAKER]

Originally Posted by bigford

so the rear leaf spring pivot nut

Yep that will work

[ihbuilder]

Originally Posted by bigford

so the rear leaf spring pivot nut

yes sir

[Lmackattack]

on a 3 axle semi tractor .....center of front axel to center of tandems.

[bigford]

what about with a lift axle in the mix?

[fhhhstix]

Originally Posted by bigford

what about with a lift axle in the mix?

The lift axle wont make a diference it is to the center of the drive axle or axles.

[JAMMER]

I could be wrong but I think you measure a wheel base from the center of the front axle to the center of the rear most axle. Ed

[Lil Giants]

Originally Posted by JAMMER

I could be wrong but I think you measure a wheel base from the center of the front axle to the center of the rear most axle. Ed

Yes you're wrong.

Center of steer to center of tandems.

If it were tri drive? I'm not sure. But likely still center of rear two axles.

[Bo Wallen]

I think it's confusing but it might help to look at this site, http://www.cdxetextbook.com/safetyIn...aswhlbase.html hope it helps.
Bo

[Bo Wallen]

I like this explanation or what it's called....Wheelbase
Manufacturers advertise wheelbase according to the distance from the center hub of the steer axle, to the center-point between the two rear wheels on a three-axle truck. So, stick a ruler vertically in the ground right in between the two rear tires, and measure from there to the steer axle. However, possibly more relevantly, officials at the DOT take literally the simplistic technical definition of "wheelbase," which is "the distance between the front steering hub and the rear wheel hub." So, when it comes time to pay tickets for bridge length permit violations, wheelbase measures from the center of the last wheel. Otherwise, advertised wheelbase is from the center of the two wheels, or from the hub of the center axle on a four-axle truck.

[cabs]

Bo they call that axle spacing

[Bo Wallen]

Originally Posted by cabs

Bo they call that axle spacing

cabs
OK......so what is the difference ? they talk about wheelbase but mean axle spacing ?! even more confusing !?

[TRUCKMAKER]

"If it were tri drive? I'm not sure. But likely still center of rear two axles".

The wheel base is always measured to the center of the main drive axle suspension.

[bigford]

well ill ask the nypd motor carrier who is scaling me now!!
how we do it.

[TRUCKMAKER]

Originally Posted by cabs

Bo they call that axle spacing

In the manufacturing arena, axle spacing would be the distance between the center line of the drive axles in the case of a truck and the "spread" of the axles on a multiple axle trailer. If you've heard of a trailer suspension referred to as a three nine, that just means 3 axles 9 feet apart. This used to be popular with steel haulers.

As far as what the DOT does...... well that's a whole new ball game

[Bo Wallen]

There is a kind of explanation on the model magazine forum, scroll down 1/3
and look at the picture. http://www.modelcarsmag.com/forums/t...bius-lonestar/ It's funny to see that nobody or everybody knows what is the right or wrong method is And DOT in each country does not make it easier either exception is lurking around.