Flatbed tandem or multi axle

If you buy a tandem, and plan to run any Western Canada, make sure it has the sliding front axle option to close up to a close spread (5' good choice) to be legal there. And if California bound, 40' kingpin to rear axle centre for any trailer over 48'.
Another good option is a tri-axle on a full slider, no downside here, and as many Western US states allow higher gross weights than 80,000 lbs, it gives additional flexibility for loads down and back from Canada, which of course has even higher gross weights.
If money is no object, a full aluminum, air ride tridem 48-53' would be an excellent choice. Rate wise, heavier loads should pay more, of course, but they frequently don't. Drywall, for example. Higher value loads pay better, and are not always heavier.
Tridum axles in the US are allowed 43,500 lbs per set, with a 10' spread, but the 80,000 lb weight cap is still in effect in most of the US for reducible loads, except many US western states which have higher gross max weights.

 

Buy a sliding tridem with a centre axle lift. I run one and there isn't a single load I can't take. I don't ever have to turn down a good paying Tridem load and when I'm in the US I lift my centre axle and have a 10'1 spread that let's me put 40k over the rear. I literally never have to worry about scaling a load.

 

This works, too. A sliding tridem without a centre lift is slightly cheaper, and there is no jurisdiction in North America that requires the centre axle to be up, 6 axle is a legal combination. A centre lift saves tire life on the middle axle, a cost consideration if available.

 

As it was stated above most northern states recognize 6 axle, but you still can't go over 80,000. Keeping that in mind if you ever go further south then your 3rd axle is useless. Having the centre lift may be more expensive but you will never have to worry about weight on your back end regardless of where you load. I run all over and most of the best paying freight runs deep south, so being able to lift my axle, push the load back and extra few feet to allow fuel weight helps greatly. More than just tires, it's ease of loading as well.

Hell this last load of forklifts I just picked up in houston puts everyone near/overweight on axles I laughed at the guy and told him push it to the back 5 feet and I'll chain it down.
12000
30000
36000
Still had room for fuel too. With a standard tridem you would be over weight, without permits.

As far as I know if you have a tridem and the front and rear axles are 10'1 apart with a 3rd axle in the middle it is still just a tridem and does not fall under the 10'1 rule. So you would be limited to 34,000. For the 10'1 to apply the axles all have to have a minimum distance of 10' from centre to centre to be considered individual axles and be allowed 20,000lbs per axle, and distance shorter than that and it is considered and axle group.

 

Hi,
Some of the above information is incomplete. Many western states allow greater gross weights higher than 80,000 lbs on reducible loads. That is why many western Canadian and US companies run multi-axle combinations into the US and back. Some jurisdictions require a separate permit, some do not. And your IRP cab card must show the correct weight you want to haul on it. A 6 axle rig would be allowed 88,000 lbs gross. These limits are set by the US federal bridge laws and the distances are in your Rand_Mcnally atlas. That is how even a super-B train can be run legally all the way down to Utah.(Many steel mills there)
Western companies know these rules, spec multi-axle combinations to work with them, and enjoy a competitive advantage to other companies. The above poster would have been fine with up to 43,500 on his trailer tridem with his fork lifts if needed, but as Texas IS a 80,000 lbs gross max state, would still have to observe that limit when loading and scaling. The same load coming out of the Port Of Seattle would have been OK also up to 88,000 if he needed it, with up to 43,500 on his trailer, provided his bridge distances were correct and he had 88,000 on his cab card. (Washington does not require an additional permit, Idaho and Oregon do.)
A common west coast combination is licensed for 105,500 lbs, the super-B maximum in Washington, Idaho and Oregon. Many of these tractors have a self-steering 12,000 lift axle in front of their drives to get 42,500 lbs on the 3 set and meet bridge limits, for instance.
In the east, Michigan has some strange combinations called centipedes, which run axles all along under the trailer, operate under permit, and cross into Ontario to haul steel from the mills around the Great Lakes..

 

You cannot gross over 80k in the US without paying extra money for permits, and your licensing. You need to read into that more before buying your own trailer.

All these companies pay extra for their permits and licenses to run those weights, look at your cab card and you'll see it in there. That your GVWR is higher than 80k meaning your company paid more to run that.

That's all I have to say at this point. 6 axles is useless in the US unless your paying extra money for the permits and licenses. Which no one will tell you, THEY ARE EXPENSIVE.

 

Some states do not require extra permits, some do. The cab card does cost a bit more when you have extra weights, it is not excessive, as all the jurisdictions are pro-rated, and most of the states are still stuck at 80,000 lbs, as the above member has pointed out. The Oregon permit for extended weights cost $8.00 annually, Montana, no extra permit. Idaho, $28.00 annually plus quarterly report. North and South Dakota, no permit .The companies that run the weights and combos over 80,000 lbs obviously charge higher rates on their tridem loads to get a good rate of return on the investment, or it wouldn't be worth it.

 

If you buy a tridem,i would put a lift on first and second axle.
That would be a very usable setup with lots off possebilities