The 311D is a modernized version of the Soviet diesel locomotive M62, offered by Newag in Poland. Most rebuilds are based on Polish ST44, but some also on the East German V 200. Only the frame remained unchanged and the bogies and traction motors were reused, but modernized. The engine is a more efficient 7FDL 12 from General Electric.

The body of the locomotives is totally new and resembles American road switchers with hoods and outside running boards instead of the old central gangway. PKP uses 27 of the subtype 311Da on the LHS line with Russian broad gauge. The standard gauge variant is only used by private operators, most of them by DB Cargo Polska.

Starting in 1960, Fablok built a small three-axle diesel locomotive for narrow gauge railways that was called WLs150. The number stood for the number of horsepower available, which came from a five-cylinder diesel engine. By 1969, a total of 144 had been built for gauges of 750, 785 and 900 mm, 33 of which had been delivered to PKP. In the same year, Zastal started production of the WLs180 with a 180 hp six-cylinder. 47 were built, of which three went to PKP. PKP called both variants Lyd1, what stood for diesel, three axles, high-pressure combustion and mechanical gearbox. 

The SM02 was the first diesel locomotive built in Poland. From 1952, 581 of these small shunting locomotives were manufactured in the Feliks Dzierzynski locomotive factory (later Fablok) in Chrzanów and sold by the manufacturer as the Ls40 type. The Polish State Railways only procured twelve examples, which were classified there as the SM02 series. With a maximum speed of 11 km/h, a range of 60 km and an output of 44 hp, they could not be used in larger train stations, which is why they were mainly used in industrial companies. The power was transmitted mechanically to one of the axles, which drove the second axle by means of coupling rods. Over time, many of the locomotives got a new type S324HL engine, which delivered either 60 or 75 hp. Many engines were still in use up until the 1990s, but most of them became superfluous due to the abandonment or dismantling of many industrial tracks. A few are still in use today, others are preserved either as a memorial or in the museum.

The SM03 was a two-axle shunter that was slightly heavier and significantly more powerful than the SM02 and was called the Ls150 or 2D by the manufacturer. It was initially made by Fablok and was powered by a six-cylinder diesel with 150 hp. Like many larger shunting locomotives, it had hoods of different lengths and a driver's cab with generous glazing. In the first series, the mechanical transmission had only one gear2q1 and limited the top speed to exactly 25.7 km/h. Later, another two-speed gearbox was used, which allowed the same speed in first gear and 45.8 km/h in second gear. The PKP procured a few more machines than from the SM02, but only used them to move other locomotives and passenger cars due to the limited capacity. The remaining machines were bought by the industry, which found a wide range of tasks for them.

The locos' nicknames were “Kogucik” and “Kaczka”, meaning “chicken” and “duck”, alluding to the small size and the looks. Since 1965 it had also been built by Zastal in Zielona Góra and a total of 273 units were built by 1969. The further development Zastal 409D was also developed by Zastal. A license-built Henschel 14H6 was used as the engine, which produced 180 hp. These locomotives were built by Zastal until 1978, then by Mystal in Myszków until 1989 and then by ZNTK Olesnica until 1995. The 409D was only used by private operators and not by PKP. A few examples of the locos can still be found in commercial use in the 21st century and some have been preserved for posterity.

The SM31, called type 411D by its manufacturer Fablok, is a six-axle diesel locomotive designed for heavy shunting and transfer service. Based on the four-axle SM42, it has a more powerful variant of the same engine with 1,200 instead of 800 hp. After the first two prototypes were bought by industrial operators, 167 locomotives were delivered to PKP until 1985. 28 more were directly built for industrial operators and designated Ls1200. Today, the last operational ones are still being used for shunting and freight trains over short distances.

A few years after the Romanian State Railways introduced the 060DA, the PKP also ordered these locomotives. They were based on licenses from the Swiss companies Sulzer, BBC and SLM and were called LDE 2100 by the manufacturer Electroputere due to their output of 2,100 hp. With a maximum speed of 100 km/h and no train heating, they were only intended for freight trains, but were also used in front of passenger trains in the summer. A visual difference to the Romanian locomotives were the large headlights. During the course of production, a revised version of the engine with the same power was used from locomotive number 156 onwards and the locomotives from number 278 onwards were slightly longer and heavier due to the preparation for central couplers. The PKP received a total of 422 units until 1985, the last of which were retired in 2019.