Originally Posted by Ford_6L_E350
I have a Ford Data Book for an 04 E-Series and it lists the E350 frame as having a section modulus of 5.44 cubic inches vs. 3.3 cubic inches for the 250. The 350 frame is listed as 7.69" x 3.18" x 0.212" and the 250 is listed as 6.16" x 3.18" x 0.181". The 350 frame is taller and made of thicker material.
I don't have experience with the cargo vans, but with the passenger vans, this is not correct. I suspect Ford put those specs in the body builders guide incorrectly at one point, and never fixed it or noticed it.
But to get the thicker frame, you have to get the EB. The RB frame is the thinner than the EB frame, and on newer vans ('08+) the E150 & 350RB are the same.
Its frustrating that even Ford can't get sh!t right when if comes to documentation. For example all of the '97-'02 EB Wagons have a full float D70, even though the specs say otherwise. The '09 Wagons in either size also got the full float, even though the specs say otherwise. I've even seen some EB wagons in between those years will full floats.
I think of it this way, the published specs show the MINIMUM equipment you may end up with, when in reality your van may have been built with something better.
But as I said, I haven't been under the cargo vans. Maybe there is a substantial difference unlike the wagons, where the split is RB vs EB. Chris would certainly know better since he's under all of them on a regular basis.