Building a log truck.

[nedly05]

I have an old Mack tandem that we don't use in our excavating business. Its a solid old truck, so I am thinking of taking the box off and adding a log rack. I have a call in to a guy who has a 16' slasher rack that he would sell, hopefully I hear back from him today. He had the rack set up to dump on a tri-axle chassis.

To make it dump on my truck, I would have to shorten it 2'. Not sure I want to do this as I might want to "re-chassis" the rack down the road if it works out, So I will just have it mounted to the frame.

So I am just looking for input from the experienced guys here, I want to do this right. What should I use for securing the rack to the Mack, how far behind the cab should I go, etc. etc.

Does anyone have any pics of log bodies they can post up??

Thanks!!!!

[snowstorm]

how long is the wheelbase? how long of wood do you plan on hauling? do you really need it to dump? did it have an under body hoist? if its not going to dump then go to a spring shop and have them bend some ubolt rods to hold body to truck frame

[gwilson]

Make sure to give it a little flex somewhere because if not it will create some flex. (cracks)

[shelbycharger400]

like qwilson said... cracks if hard mounted

Thats why you see "proper" mounted dump beds , flat beds,  cube/van chasiss on trucks  they use WOOD with 12 to 14 in long U bolts.    Oak is best.

[Maine372]

if its already rigged up to dump just move the hinge point two feet ahead. that two foot overhang will help keep the weight on the tandems(rather than overloading the front axle) and it shouldn't swing down far enough to hit the ground. if it doesn't need to dump just crank it down with some u bolts, or threaded rod and two plates. definitely use the oak stringers between the frame and body.

[Woodhauler]

I have owned and drove tri axle log trucks for 30 years, and NEVER put wood between the frame and body! Gripe them down tight and you don't need it! My log body is 7 years old and never had a crack in it!

[snowstorm]

do not use threaded rod its way to weak. its grade 2 at best. most dont use wood if its in there long enought it will rot. your dump body didnt have any wood under it

[Autocar]

The new ones Ive seen they bolt directly to the truck fram and there slide closer or further apart for what logs length you may be hauling. I aways set mine up on oak 1x4's and have never had any problems,but I can see where you can crack welds crossing a road way ditch and twisting coming back onto the road.

[CTL logger]

I've built 6 tri-axle log trucks we never used wood on frame I also never had a sub frame, had 4 bunks directly on frame used u bolt material to attach them. Took 5/8" plates with 4 straight bolts welded nuts on one end tightened other end never broke a bolt and with the fine threads of u bolt stock once you got them tight they stayed tight.

[nedly05]

Thanks for the replays fellas, I knew I'd get a ton of good info here! The rack I'm looking at is professionally built, and I'm really intrigued by the dump feature. It was built to go on a dump truck with a 16' box so it could be switched back and forth. The crappy part of that is that all of our tandems have 14' boxes. It would be nice to be able to have a truck that could switch back and forth. I'm hoping to run over and look at it today, if its not a big deal to do, moving the hinge forward 2 feet might be a good option

Does any one have any pics of the mounting to the frame? What grade is u bolt stock??

Thanks!!!

[snowstorm]

u bolt rods are grade 8

[nedly05]

A little update on this truck... I got looking it over pretty good, and theres some significant rust jacking in the rear of the truck, so no log truck, at least on this one. Thinking of cutting the bad frame out and making a single axle tractor out of it.