Leave your thoughts Sometimes referred to as concrete leveling, mud jacking involves pumping a mixture of water, soil and cement beneath a sunken concrete slab to raise it back to a level position. This hydraulic process of “floating” the slab back to a level or predetermined lift is actually quite simple. First, holes are drilled into the concrete slab, and then the “mud” is pumped into the holes, filling the void beneath, which lifts the slab. This is the most economical alternative to removing and replacing the damaged concrete. Mudjacking is primarily used to repair sunken driveways, sidewalks, roadways, walkways and other types of exterior concrete slabs. It’s not recommended for residential monolith or interior slab raising.