[2]: 56  The conversion process was suddenly halted in 1924, with partially converted cars being patched up and returned to service as steam-hauled carriages, with their original codes and numbers.

When that system was abandoned, motor cars all became 2nd class, except for six which were retained for special duties (AM), and the double-ended single units (ABM).

The frames and electrical equipment were retained, and were rebuilt with new bodies of the current Tait design, being renumbered 442M and 443M.

At the terminus, the motor cars would be uncoupled and the remaining carriages split, with steam engines hauling each portion to Warburton or Healesville, or Mornington or Stony Point, respectively.

In the original electrification plan a group of ten single-unit, double-ended motor cars were proposed for use on the St Kilda and Port Melbourne lines during lower-patronage periods.

By 1914, a conceptual diagram had been drawn up for double-ended composite motor cars, although no detail was given about the use of those vehicles if any were built.

[3] This group of vehicles were to be constructed similarly to the rest of the Swing Door motor fleet, with a large guard/driver compartment at one end.

After World War II, the population of Melbourne boomed, and with it the need for increased suburban parcel traffic capacity.

Otherwise, the sides were completely stripped and replaced with a similar style to that of the Tait parcel van fleet, though the car maintained its thinner body of 8 ft 6 in (2.59 m).

Outward-swinging doors were kept, in three pairs, at spacings which divided the car into four roughly equal sections, although the outer two were partially driver's compartments.

When complete, 10CM was painted in blue with a thick yellow stripe along the sides, curving to a point in the middle of the ends.

They were converted to further parcels coaches as a stopgap measure while 10CM and the repaired 3CM were busy with various electrification works, so the conversions were minimised.

Instead of a full rebuild, the seats were removed and a walkway down the centre was cut between all the compartment partitions, but the cars did not have the sides replaced, and they stayed red.

It had its seating removed and the destination board replaced to show "parcels van", for use as a relief vehicle when any of the Tait CM coaches were unavailable.

It spent the rest of its time as a pilot in Jolimont Yard,[5] performing shunting around the sidings and in the workshops, and had been fitted with a second pantograph by 1948.

By the late 1970s both vehicles had been repainted into a scheme similar to the parcels vans, and were officially allocated to the Jolimont yard pilot roster, with small lettering above the middle-side [1].

Near the end of its career, 156M was painted in all-over green in place of its previous blue livery, but retained yellow stripe along the sides.

The driver's compartment took the first 2 ft 10+1⁄2 in (0.876 m) and about half the width of the carriage, with the guard's elevated seat directly opposite.

From approximately 1908 to 1922, the bogie passenger fleet had underframes and bodies extended to increase the capacity of any given train, by wasting less space with couplers and buffers.

A further re-classification of 1st-class T cars was made in 1940, when a shortage of 2nd-class accommodation on the suburban system became evident, the situation being exacerbated by the introduction of petrol rationing during World War II.

In 1958, one-class travel on Melbourne suburban rail system was introduced, meaning that the fourteen BT trailers no longer needed to be different from the rest of the fleet, and all cars were progressively fitted with upholstered seating as the new standard.

Those later conversions (and probably the earlier ones as well) included a shunter's cock being added, similar to Tait G cars, to aid coupling three-car units (M-T-BT-) to four-car blocks (M-T-T-M).

Some cars were converted to workmen's sleepers, but the majority had valuable fittings removed and were railed to Allendale on the former North Creswick - Daylesford line, where they were burned.

During the Easter and Christmas seasons, the Tait G cars (T-type trailers with gas lighting installed, as well as electric) would be withdrawn from suburban service and used to provide extra capacity on country trains.

At the time 282 Swing Door vehicles were available, after accounting for 18M and 44M converted to Tait, three trailers returned to steam-hauled use, 122M and 123M withdrawn 1956, 156M permanently allocated to Jolimont Yard and 157M in use as a parcels van.

The final seven-car set, 137M-71T-6T-67M-12BT-34T-138M, was withdrawn from the Princes Bridge (Epping and Hurstbridge) routes on 28 February 1973, and the last run on the Altona branch took place on 2 October 1973.

The final regular use of a Swing Door train was on the Port Melbourne roster in the morning peak of 4 December 1973.

Cast-frame bogies from scrapped Swing Door trains were recycled for use under the Y class diesel locomotives built in the 1960s.

Motor car 8M, with unique curved wooden panelling, has been preserved as a static exhibit at the Newport Railway Museum, without its electrical equipment, and the condition of 13BT led to it being exchanged for driving trailer 24D.

[11] A special "farewell" day for Swing Door trains was held on 26 January 1974, with set 107M-32D-24D-137M running shuttles between Flinders Street and Port Melbourne.