KRAUSS MAFFEI ML 4000 QUESTION

[T]

I know that the D.R. G. & W. had KM ML 4000's  with porthole windows as well as S.P.  However the S.P. version had WALK WAYS . My question here is :  Which Locomotive Builder built them or was  the IMPORTER of the D.R. G. & W. and the S.P. KM'S  KRAUSS MAFFEI's ? 

Tom

[icghogger]

All of the K-M ML-4000 locomotives were built by Krauss Maffei of Germany. In 1961, the original six were built with cowl-type bodies, each locomotive had two 2,000-hp, 16-cylinder, 1,585 rpm Maybach MD870 engines coupled to Voith transmissions with drive lines geared directly to the axles of the German designed trucks. The D&RGW owned three but was not satisfied with theirs and sold them to the SP, who also owned three of the original order. In 1963, the SP ordered 15 more from K-M but wanted them to follow US locomotive design practices, specifically with road-switcher (hood) type bodies, modified cabs and General Steel Castings (GSC) trucks. These locomotives had the high-speed 2,000-hp Maybach V-16 engines, which was contrary to SP’s design preference. All were assigned to Roseville, CA. Due to drive shaft failures and high maintenance costs for the high-speed German diesel engines, they proved unsuccessful and were retired by November, 1968.

[icghogger]

The SP still wanted to utilize the diesel-hydraulic technology and turned to a US manufacturers to try again. Alco designed and built three DH643 units in 1964. Each had two 2,150-hp 12-­­cylinder 251C engines coupled to German Voith hydraulic transmissions under a license agreement. The prime movers, of the type used in SP’s Alco RS32s, faced opposite each other with the radiators in the middle of the car body and the transmissions below. The drive shafts from the transmissions to the trucks were of a heavier design than those employed in the Krauss-Maffei locomotives. The DH643s rode on a tri-mount truck that had been standard on Alco six-motor units since 1950.

They initially performed well on the SP, and reportedly, they could haul twice the tonnage of a diesel-electric with the equivalent horsepower. Like the Krauss-Maffei units, the DH643s were based out of Roseville and primarily used on San Joaquin Valley runs. They were frequently paired with at least one F7. Maintenance issues took their toll on the Alcos. In particular, there were instances when brass flakes were noted in the truck gear boxes, necessitating costly repairs.

No additional DH643s were ordered, and no other road expressed any interest. Orphans on the SP roster, all were retired in 1972.