I don't have an M54, but I do have a M812,M51a2 and a Deuce. The deuce is nice, great on fuel. but a five ton drives much better.The power steering is great and for some reason rides and handles better. I averaged about 7-8 mpg on a 370 mile trip. There are two differant turbos on the five ton multi fuel,much like the Deuce.One is only audible under a heavy pull .the other whines as soon as You hit the starter.You can tell them apart by the way they look.the Whiner has a small tube on the lower rear of the turbo housing,below the exhaust pipe .(waste gate?) I have also noticed my five ton smokes like a freight train on a long heavy pull. also like mentioned before,there could be some license issues.the plates will be more expensive,and the parts are much heavier.Keep the wife,ditch the other truck.