So, I have had my B7100D for a while (10 months) and pretty much understand the B's as CUTs (compact utility tractors). I thought after a while I would understand the others better, but even after following the forum this year I am not picking up on the basic differences, primarily the L. I sense the M's are what I would call the full size tractors, ie, what I was used to on the farm. The BX's are the sub-compacts. What are the L's? Most that I see are 2WD and 2 cylinder, but higher horspower than some of the earlier 3 cylinder B's.
Re: What is the difference between the M, L, B, & BX?
I think the letter designation is more related to actual tractor physical size and not horsepower ratings as there are many of the earlier L series tractors that are under 30 horsepower rating.
I also think that at some point the line got blurred even more as there are some Newer B series machines that are bigger than some early L series machines.
Many of the New BX machines are heavier and have substantially more power than some of the early B series machines and even some of the early L series machines.
So while it is logical that the series letter designation started as a way of dividing the machines by size and horsepower as newer and improved models were designed and built the overlap between newer and older models of different letter series increased.