What type of bomb was used in oklahoma city bombing of 1995

Actually, it wasn't really a specific type of bomb, but in fact, it was a mixture of very powerful ingredients. 
It was a mixture of ammonium nitrate, fertilizer, nitromethane, and diesel fuel. In fact, it was 4,800 pounds of this mixture jam-packed into a truck and detonated right in front of the Alfred P. Murrah Federal Building, which was 9 stories tall.