What is the extra axle/wheels for on dump trucks that doesn't touch the ground?

[zixxer]

I see dump trucks that have three rear axles - two with tires on the ground, and one axle slightly forward but like a foot or so higher... what's the purpose?


http://www.flexleasefinancial.com/2006%...onal%20Dump%20Truck%201%20MVC-001S.JPG

 

[leftyman]

If the truck is permited to haul over 80,000 lbs the extra axle is needed to distribute the weight. Trucks are weighed by axle as a safety feature.

* weight might be different by state or country*

I finally get to answer a question based on my job experience :thumbsup:

 

[jiggahertz]

Originally posted by: leftyman
If the truck is permited to haul over 80,000 lbs the extra axle is needed to distribute the weight. Trucks are weighed by axle as a safety feature.

* weight might be different by state or country*

I finally get to answer a question based on my job experience :thumbsup:

How does it distribute weight if the wheels aren't touching the ground?

 

[purbeast0]

Originally posted by: jiggahertz

Originally posted by: leftyman
If the truck is permited to haul over 80,000 lbs the extra axle is needed to distribute the weight. Trucks are weighed by axle as a safety feature.

* weight might be different by state or country*

I finally get to answer a question based on my job experience :thumbsup:

How does it distribute weight if the wheels aren't touching the ground?

I'm guessing it can be lowered down.

Cool though, this is one of those things I've always wondered too but never looked up.

 

[Quasmo]

Originally posted by: jiggahertz

Originally posted by: leftyman
If the truck is permited to haul over 80,000 lbs the extra axle is needed to distribute the weight. Trucks are weighed by axle as a safety feature.

* weight might be different by state or country*

I finally get to answer a question based on my job experience :thumbsup:

How does it distribute weight if the wheels aren't touching the ground?

maybe they drop down and engage at that point. otherwise you're wasting gas.

 

[KLin]

Originally posted by: jiggahertz

Originally posted by: leftyman
If the truck is permited to haul over 80,000 lbs the extra axle is needed to distribute the weight. Trucks are weighed by axle as a safety feature.

* weight might be different by state or country*

I finally get to answer a question based on my job experience :thumbsup:

How does it distribute weight if the wheels aren't touching the ground?

Great question!! :thumbsup:

 

[leftyman]

In regular use the axle is disengaged and raised to prevent wear on the tires and brakes. Before a truck is loaded heavy the axle is engaged.

trucks are never loaded without knowing the weights..almost all pay rates on deliveries are based on weight and miles.

trucks are either loaded on scales or weigh in after loading. if a truck isnt permited to haul overweight then it isnt loaded above state regs.

 

[jiggahertz]

Originally posted by: leftyman
In regular use the axle is disengaged and raised to prevent wear on the tires and brakes. Before a truck is loaded heavy the axle is engaged.

trucks are never loaded without knowing the weights..almost all pay rates on deliveries are based on weight and miles.

trucks are either loaded on scales or weigh in after loading. if a truck isnt permited to haul overweight then it isnt loaded above state regs.

ah ok, makes sense

 

[Glayde]

Yeah the load axl can be lowered from inside the truck.

When you are running a lighter load, you want it off the ground to save gas, but when you are loaded enough, you need, for law and safety purposes, to drop the extra axl (or two) to distribute weight among the axls.

 

[ebaycj]

Originally posted by: Glayde
Yeah the load axl can be lowered from inside the truck.

When you are running a lighter load, you want it off the ground to save gas, but when you are loaded enough, you need, for law and safety purposes, to drop the extra axl (or two) to distribute weight among the axls.

I don't think we were talking about Axl Rose of Guns 'n Roses.

 

[pnad]

Not only do you save fuel and wear but it is a bit of a chore to turn a corner with that extra set of wheels down scrubbing the road.

 

[herkulease]

because they like to sell axles in pairs? so they slap it on and make it easier.

 

[thirdeye]

Interesting, I kinda figured it was for some reason like that, but never really bothered to give it much thought.

 

[NiteWulf]

They also help to lower the center of gravity of the trailer