Green’s Dictionary of Slang

freight (it) v.

1. to travel a long distance.

[US] ‘Kansas Land’ in Lingenfelter et al. Songs of the Amer. West (1968) 462: I have ‘freighted’ many a mile.
[US]A.H. Lewis Wolfville 167: When I sees him first is ages before, when I freights with eight mules over the Old Fort Bascombe trail from Vegas to the Panhandle.

2. (US tramp) to travel on a freight train.

[US]‘A-No. 1’ Mother of the Hoboes 67: Tonight we’ll freight it down to New Orleans.
[US]W. Guthrie Bound for Glory (1969) 408: I sung her another made-up verse: ‘I’ve freighted and barged it from New York and up’.