Hauling Two 40'

MA and NY also require an LCV license to haul 48' and 53' 'turnpike doubles'. You need a minimum of 5 years experience and a good driving record to get this license.
Some Western states which permit triple pups also allow like 42' doubles, but that's only 3 or 4 states. Maybe states which allow 'mountain doubles' (48' and a 28') might allow these. I know Navajo has a few of these 40'-ish double sets for very specific contracts.

And, as for 'turnpike doubles', I remember some 25+ years ago 1 company had a special permit to run double 57' trailers (of empty beer cans headed to the KCMO Budweiser bottling plant) down the Kansas turnpike. THAT looked like a handful!

As for Canada, If you are driving A-doubles, I believe 28'6" is the longest in Ontario. Lots of B-double variations, some with the longer forward, some with the shorter forward. Saw lots of B-double container rigs with a 20' on the lead and a 40' on the tail. 'Turnpike doubles' are allowed in Saskatchewan (I think?), but certainly in in Alberta. Don't know about MB, Yukon, or NWT, etc. "Train Routiers" in Quebec are similar to turnpike doubles, but are allowed only 9 months out of the year. But you wouldn't be able to get a rig like that across ON to get to PQ....

 

I know a few years back, double 48’s were allowed on the Indiana Toll Road. Drivers needed a special license, and I believe the tractors needed to able to at least maintain the posted minimum speed on inclines. Had heard a few stories of a few ‘trains’ being pulled over, and the company cited for failing to maintain speed.

 

Not sure that anyone can help you @Dam1975 from what you say. Whatever configuration you end up with I would have thought that the 40 foot/20foot limit has you snookered.

I drove A-triple trains in the Northern Territory of Australia back in the '60s before B-trains were even invented I think. So I have never driven a B-train and, apart from the overall length benefits, can't see the point of them. Obviously a view that is challenged by people with direct experience

I suppose my view is formed by the fact that in the NT triples can be driven through some towns so the shorter cut in of an A setup is important,
I'd be interested to see if you find a way though.

 

I doubt BC will give you a permit for what is basically a divisible load, especially since you’d end up with so much overhang off the back. They’re pretty strict when it comes to tractor wheelbase and trailer length from what I can remember. The last time I was up there was 2018 and I had a 53ft trailer, 244” wheelbase tractor, and it was sort of a pain to get permits to haul 60ft beams.

I don’t know where you want to go or what you’re trying to accomplish but personally I wouldn’t want to be trying to get around Vancouver with over 80 feet of trailers behind me. WA and OR both limit how much trailer you can have with doubles and any overhang needs to be between the trailers, zero overhang on front or rear, so that’s a no-go for you there.