I checked the Greenberg guide to Lionel Trains 1970 to 1991 volume II. It is not a cataloged set, nor a service station set. @Grampstrains is probably right, perhaps a Sears set. The Greenberg guide states that the 8040 Nickel Plate Locomotive was made in 1970-72.
The sticker on the box with the set information, covers over another 2-4-2 steam engine, the red strip on the box engine looks like the 8141 PRR locomotive. That engine has smoke and sound of Steam, so a more substantial engine. So, the box may represent a slimmed down version, with no smoke, and Lionel just put in the box whatever inventory they had in stock.
The 1972 Lionel Catalog had a set with the 8040 Loco with tender, and three other cars. So, your set has one more car, so that could be something that would be offered in the Sears catalog that was differentiated from the Lionel Catalog. There is also an outside chance that it could have been a JCPenney offering.