@Alanj: Mudjackers have very specialized equipment. For example: They use drills with 1 3/8" holes. The pump used has a pumping pressure of 2400 psi. A cement mixer mounted to the back of a truck.
This is not a procedure for the do it yourselfer. Also, it is very hard work. My advice is to just call your local Mudjack company and let them handle it.