In late 1998, SLM completed the extensive modernization of 52 series German Kriegslokomotive 2-10-0 no. 8055 for use on the Orient Express in Europe. The locomotive was extensively tested prior to being modified so that the benefit of the modifications could be documented. Over 70 percent of the parts of the locomotive were replaced or modified. As a result of these modifications, the top speed of the engine was raised from 70 km/hr to 100 km/hr and the horsepower was increased from 1600 to 3000. The engine now burns light oil and features sealed roller bearings, a central lubrication system, light weight motion-work, and extensive thermal insulation. A side benefit of light oil firing in an external combustion engine (i.e.- steam) is very low exhaust emissions. This engine emits about 80 percent less toxic exhaust gases per kW than a state-of-the-art diesel. The modifications were performed to provide a steam locomotive which could keep tight schedules and "time windows" to be allowed to run on the main lines without causing interference with normal trains. Testing of the modified locomotive began in March 1999 and the locomotive pulled its first passenger trains in April 1999.