Lionel 675 history

The Lionel 675, 2025 and 2035 locomotives are three of the most iconic and sought-after engines Lionel produced in the postwar era. They depicted the Pennsylvania K-5, an ill-fated 4-6-2 Pacific locomotive that was intended to replace the iconic K-4, a popular locomotive that had roamed the rails for one of the largest railroads in the United States since 1911, and was later recognized as the official state locomotive of Pennsylvania. Unfortunately, the K-5 proved less successful and only two were ever made, although the PRR did run both of them into the 1950s.

Some documents identify the 675/2025/2035 as a K-4, but Lionel’s own service literature from the period says it was a K-5.

Lionel’s version proved far, far more successful than the real thing, almost becoming an icon itself. The first edition of Krause’s Standard Catalog of Lionel Trains, 1945-1969 featured a Lionel 675 from 1946 on its cover.

Lionel introduced the 675 and 2025 in 1947. Lionel marketed the 2025 as an O27 locomotive, but either will run on O27 track as the two engines are mechanically identical. The 2035 succeeded them, adding magnetraction, in 1950 and 1951. The 675 and 2025 returned, in slightly cheapened form, for one final year in 1952.


From an operator’s point of view, the 2035 is perhaps the most desirable version of Lionel’s K5 because it has magnetraction. This increases its pulling power and ability to climb steep grades. However, the early 675 and 2025 run a bit more smoothly. Some collectors believe Lionel built them to closer tolerances than the 2035. The 1952 version of the 675 and 2025 are the least desirable since they don’t run as smoothly as the early versions and don’t have the benefit of magnetraction. They’re still good locomotives, just not quite as good as the early ones had been.

The easiest way to tell the difference is to look at the rear trucks. A 1952 version came with a simple four-wheel rear truck, while a 1946 or 1947 version originally came with a more ornate diecast two-wheel truck. But it’s easy to change trucks, so a more foolproof method is to look at the six driver wheels. The more desirable versions have ornate Baldwin-stamped wheels with a larger number of spokes and a nickel-plated rim. The later, less desirable version has a smaller number of spokes and doesn’t have the nickel-plated rim. It looks less expensive.

There are plenty of 675s and 2025s out there. That means an operator can buy an imperfect or restored one and get a really nice-running train for a reasonable amount of money.


For the collector, chasing down the variations of these three locomotives presents a bit of a challenge. But it’s not an insurmountable one. There are five variations each of the 675 and 2025, and two variations of the 2035. The less common variants are more valuable, but the difference in price is generally less than 10%.

I’ve never understood why, but virtually every Lionel locomotive I’ve purchased secondhand from its original owner was missing parts. I guess I can extend that to my dad as well. The best of his childhood locomotives was missing a good number of parts when I encountered it. Perhaps kids would disassemble the trains when they were bored with them in an effort to figure out how they worked, then had difficulty getting them back together and parts like leading and trailing trucks got misplaced.

All of the easiest parts to lose are interchangeable between the different variants of Lionel’s K5s. So it’s entirely possible, even likely, that you will find them today in configurations that Lionel never shipped from the factory, due to hobbyists replacing missing parts over the decades.

Fidelity and scale

Lionel’s versions are recognizable as PRR K-series locomotives. But the ability to mistake them for the K4 is enough to tell you they aren’t scale models. The wheel arrangement was incorrect. The real K5 had a 4-6-2 arrangement, as opposed to the early 675/2025 2-6-2 arrangement, or the 2-6-4 arrangement of the later versions.

They scale out to approximately 1:55 scale. That makes them larger than many of Lionel’s O27 locomotives, particularly the starter set locomotives, but still undersized for O scale. The earliest models had the numbers 675 or 2025 in the front. Lionel soon changed it to 5690. Since I know someone else will check the number if I don’t, I checked. It turns out the real PRR 5690 was a boxcab electric, not a K5. The actual K5s bore numbers 5698 and 5699. Sticklers for detail weren’t the target audience.

Buying tips

When shopping for a 675, 2025, or 2035, pay attention to the boiler front. Frequently one or both marker lights are broken off. Replacement boiler fronts are available on Ebay and they aren’t terribly expensive, but factor that expense into your purchase price.

Also, to protect future resale value, make sure the locomotive comes with the correct tender. The 675 and 2025 came with a 6466W if the locomotive stack is black (indicative of 1947 or 1952 production). They came with a 2466WX if it’s aluminum (indicative of 1946 production). Some 1946-produced 675s and 2025s have been reported to have come with 6466Ws, but my sources conflict on that. The 2035 came with the 6466W. Lionel trains shouldn’t be considered investments. That said, the more complete and correct your purchase is today, the easier it will be for you (or your heirs) to recoup at least some of your money in the future if necessary. The Lionel K5s have held their value better than many other postwar Lionels in the last couple of decades. That’s a tribute to their enduring popularity.