clemsonfor
Super Member
I went and looked at the 1975 Nebraska Tractor Test - YM240 (pdf) [a 'Consumer Reports type lab test] but they didn't measure lift.
One thing they did document is Hi range first gear is lower than Lo range 4th, something we have subjectively felt.
Also they observed 210 degrees coolant temperature in their full load 2 hour test.
There's lots of interesting data in that report.
Not only have we felt that the ym240 service manual says this. It gives ground speeds in each gear . If you want I can post a picture of the page.