Heavy spec truck purpose?

We're I work we use trucks like that pulling our end dumps and opentops. We used to run the landfill every day so the heavy spec trucks hold up better.

 

Lots of trucks pulling multi axle trailers are tandems. My tractor is a tri axle but when I pull our super trailer I don't use the drop axle.

 

To keep them from breaking. Over weight permits will allow you to go heavier on your axle groups. We can permit up to 62k on a tridem set of axles. I have a buddy that thought a Mack vision 460 was a good truck because he got a good deal on it. He put it under a belly dump and within a year the frame was broken.

The gearing just helps you get the heavy load moving easier.

 

I knew a guy who owned 2 Mack visions with standard 40k tandems.They broke many axle driveshafts while at the landfill.Sold 1 and the other one got heavier axles.

 

Those trucks from Canada were used for B train work. That's a pretty standard B train spec for western Canada

 

That's a pretty typical Canadian spec. 1/4" frames, 40k lbs rears and 12k lb steer axles just don't hold up off highway. Us Canadians (out west anyways) don't really use drop axles for heavy haul. Usually we'll run tridrive trucks (triple 23k lb drive axles, 69k lbs total), or we'll pull a jeep (single axle, tandem axle or 16 wheel depending on the weight)

 

Or we'll use beds like these:

 

Alberta doesn't allow lifting axles on truck tractors. If you have one they want to chain it up so you can't use it. That is one reason some are running 3 powered drive axles.

 

Yep our trucks are heavy spec'd as well... We pull multi-axle walking floor trailers and end dumps. They put up with more abused on off-road applications... It's not very often in Ontario that you will see a tri-axle tractor, not to say we don't have them but not very many of them around. Most of the heavy spec'd tractors with a lift axle are pulling RGN's...

We have 46K rears and 14.5K steers, 3.73 gearing, full lockers, double frame front to back, 18 speed.. We run Detroit 60's in the FLD 120s and DD15's in the new Coronado's. We are not a short wheelbase tho, we have a wheel base of 213" ... We could fit a drop axle if we needed, but pulling a multi-axle trailer with our spread we don't require one on the truck..