On Wed, Jan 20, 2021 at 04:02 PM, Dave Parker wrote:

t gets weirder with the PRR Crown trucks.  If you are looking at p. 608 of the 1919 Cyc, you'll see two line drawings and one image/photo, all three seemingly for the 70-ton version.  The line drawings both show the 5-10 WB.  But the head scratcher for me is that there are three different spring packages:  6-spring, 5-spring, and what looks like 4-spring in the photo, but I suppose could be a 5-spring without any of the central spring visible.  The photo of a 2E-F2 that I shared yesterday has the obvious 5-spring package.

Well, I don't know anything about Crown trucks, and don't claim to, but my impression is:

The caption of the 5'-6" wheelbase truck is in error, and it's really a fifty ton truck.
As to the 5'-10" wheelbase trucks, it's one sideframe designed to serve as either a 70 ton truck, or for those 85 and 90 ton coal cars both the PRR and N&W were developing, depending upon the spring arrangement installed.

But that's just a guess on my part. I'll leave it for the Pennsy fans to sort.

Dennis Storzek