The Transformer Car No. 6818 was produced on a RED molded chassis with heat-stamped WHITE serif "LIONEL" lettering on both sides. The number "6818" appears to the left of this lettering. It came equipped with early AAR trucks with disc operating couplers on both ends.
Produced only in 1958, this flat car’s transformer differed in several respects from its predicessor that was used on the No. 6518. Two notches were added to the inside of the ends of the transformer. These aided in the alignment of the transformer to the molded axle retainers that are found on the military car loads that were used on the No. 6803, 6804, et al. The two brass nuts that were used for holding the transformer to the No. 6518 were removed. Also, the heat-stamped number "6518" on the bottom of the transformer was changed to "6818" to match the number stamped on the car’s chassis sides.
There are two variations:
Variation A: Uses chassis mold No. 6511-2.
Variation B: Uses chassis mold No. 6424-11.