The class J locomotives were designed for the electrification of the northern half of the D&H, so they were built as hood units instead of as boxcabs. They are slightly higher horsepower than the prototype, and use a smaller, but equipment-free, cab.

18 were built in total – 10 for the PV&T, 3 for the M&B, and 5 for STCUM’s Deux Montagnes line.

In 1990, #619 was rebuilt as a multi-system prototype for operation on the OSW’s Windsor Terminal Railway. It continues to operate there to this day, serving the few remaining online industries on the line. Yes, it was built with third rail shoes just in case the CPR and CN wanted to reelectrify the Michigan Central Tunnel. No, the tunnel was not electrified, and yes the third rail shoes have not been used in the 35 years since 619 was outshopped. And, no, the third rail shoes are not going to be removed.

Yes, this does not make very much sense.

Over the years, the class J motors have been slowly upgraded to class JS specs and those rebuilt units can be found almost everywhere on the electrified system.

The M&B units eventually found their way onto the PV&T roster after the PV&T & CV purchased the M&B, as did the Deux Montagnes units, which were purchased after Exo retired them (Deux Montagnes was converted to a light metro, so Exo no longer had any use for railway gauge motors.)