Thinking of upgrading from a 7.4 to a 8.1 Gasser

Be prepared to deal with the AutoRide magnetic shocks, they will be shot at that mileage. $250 each to replace or otherwise bypass the system and go with aftermarket shocks.

Spark plugs don't go to 100k and also don't need a professional to replace, they are some of the easiest plugs to change. If the vehicle is a from a salt belt winter state, check the brake lines for rust.

Tow capacity is 12k with the 4.10 axle, 10,500 with the 3.73.