Review by Jason Quinn/photos by the author
EMD’s GP40 is an exciting new model in Rapido Trains’ catalog of HO-scale offerings. This addition is a natural progression from the hobby manufacturer’s prior GP38 release (see Ryan Crawford’s “Southern Charm” review of Rapido’s Norfolk Southern GP38 in your March 2025 MRN). The two four-axle locomotive prototypes share many characteristics, with the long hood being the location where the two exhibit the most differences. The GP38 model is a non-turbocharged 645 prime mover producing 2,000 hp whereas the GP40 is powered by a 3,000-hp turbocharged 645 prime mover.
General Motors’ Electro-Motive Division first produced its GP40 in November 1965. The new locomotive was the successor to the GP35 model. The GP40 had many upgrades over the similar GP35 model. The GP35 was the last model to use the EMD 567 prime mover. The 40-series units introduced the 645 prime mover; this was the single biggest change from the 35 to 40 series. The GP40 also rode on a longer frame (3 feet longer than the GP35) and had three 48-inch radiator fans, versus the GP35’s two 48-inch and one 36-inch fan arrangement.
ABOVE: MKT 501 at Parsons, Kan., in November 1986. Katy built this slug from from GP40 222 in 1976. The other slug added to the roster at the time was 500, which came from MKT F7A 74A. Both slugs moved to Union Pacific’s roster in 1988 with 501 carrying S300 and later UPY926 numbering. —T.N. Colbert photo, Kevin EuDaly collection
Production of the GP40 model ended in December 1971. 1,242 were produced, with the majority (1,187) sold to 28 railroads in the U.S. The largest quantity of GP40s was found on Penn Central’s roster with 170 units; these were added to the 105 units New York Central purchased before 1968 and the arrival of Penn Central. The combined fleet clearly put Penn Central/Conrail as the largest operator. Chessie System comes in second place with 161 units from Baltimore & Ohio, 50 from Chesapeake & Ohio, and five from Western Maryland. The smallest order was a single unit sold to Toledo, Peoria & Western Railway (TP&W); this GP40 was an EMD warranty protection unit that became available and joined the road’s roster around 1970. This unit was later acquired by Santa Fe and was that road’s only GP40 on the roster, but didn’t enjoy a long tenure for the railroad. Santa Fe rebuilt TP&W’s GP40 into a GP35u; however, it was soon wrecked, and later scrapped.
Rapido Trains provided not only a GP40 to review but also a slug unit. Rapido has really been hitting the market with slugs lately. This is an overlooked area in the hobby. I com-mend Rapido Trains for their efforts in expanding this unique and uncommon motive power area in HO. My sample is decorated in the green and yellow colors of Missouri-Kansas-Texas (MKT) or often better know as “the Katy.”
The slug is unique to MKT’s roster (Union Pacific after 1988), while the GP40 tooling has opportunities for releases in several road names. In this run, Rapido Trains produces HO-scale GP40 diesel locomotive models in three Canadian National styles; “Death Star” era Illinois Central; Richmond, Fredericksburg & Potomac; St. Louis-Southernwestern “Cotton Belt” in as-delivered appearance; mid-1990s Wisconsin Central; Western Pacific silver Zephyr livery with orange band; and 1990s era Union Pacific featuring “We Will Deliver” slogan, offered with and without a slug in this run.
My GP40 and slug sample is two-thirds of MKT’s “three stooges” set. The interesting nickname was given to the trio by Katy employees. GP40 222 was wrecked and built into a slug, which is nothing more than a weighted platform with traction motors. The slug receives power from its two mother units. MKT GP40s 226 and 227 were specially equipped for this service with the addition of power cables required to transmit power to the slug. The slug does have nicely detailed power cables, but the GP40 mother unit seems to lack the proper connections (I could not find any good rear pictures of the GP40 units to confirm this though). This set includes MKT 226 GP40 and 501 slug. Rapido offers MKT GP40s separately in three road numbers: 194, 216, and 227.
The two models come in one large flat box encased in Rapido’s traditional clear plastic clam shell. This sturdy box should keep these finely detailed models safe under all but the harshest traveling conditions. As I unpacked the pair, I found these replicas to be free of any damages or blemishes. My first impression of these models was “Wow!”