I own an f250, 7.3 deisel that has had the complete rear end
swapped out, (due to wreck damage) i am not sure that the
correct ratio rear end was put back in the truck...help
serial no. Of truck: 1ftnw21f73ea84022
tag on rear end: S 409 b, l731058e22, 75w140 synth oil only
can anyone help me?