The last two, built in 1929, also had Lentz poppet valves but in this case the cams rotated in one direction, the camshaft being driven from the leading right-hand driving wheel by means of two pairs of bevel gears and a longitudinal shaft on the outside of the wheels.

4,200-gallon tenders (a type of which more than a thousand were produced between 1924 and 1952) having a water capacity of 4,200 imperial gallons (19,000 L), a coal capacity of 7 long tons 8 hundredweight (8.3 short tons; 7.5 t) and a wheelbase of 13 feet 6 inches (4.11 m); all were equipped with water scoops.

This was done because the J38s were used in Scotland, where there were no water troughs on the LNER system; and the larger capacity was not needed for the short journeys that the J38s usually worked, so the larger tenders (with scoops) could be more usefully employed with the D49s.

By the late 1930s it was realised that the water scoops of the D49s were largely unnecessary: the 23 based in Scotland never used them, whilst the remainder of the class were all based in the North Eastern Area, which had just two sets of water troughs: at Wiske Moor, north of Northallerton; and at Lucker, both being on the East Coast Main Line, a route not used by the majority of D49 workings.

In 1941–42, a steel shortage meant that 25 new class O2 locomotives were built without tenders, receiving G.S.

The last two orders (totalling forty) again took blank numbers, this time scattered between 201 and 377.

2753–60 became 2728–35, these all had "shire" names; whereas eight locomotives whose old numbers were scattered between 217 and 279 took the vacated nos.

Later in 1948 a comprehensive renumbering scheme was devised and put into effect, under which the final LNER numbers were increased by 60000, class D49 becoming 62700–75, and this was completed during 1950.

Since March 1961 it had been used as a stationary boiler in Slateford, and continued in this role until January 1962.

In July 1964, it was purchased by Ian Fraser who had it overhauled at Inverurie Locomotive Works in January 1965, during which it was repainted in LNER green livery, with its original number 246 (which it had carried until November 1946).

The locomotive was not restored to original condition: it had screw reverse (which replaced the steam reverse in June 1929); it lacked a Westinghouse brake pump (removed in December 1930); and it had an ex-Great Central Railway tender (which replaced the LNER tender in June 1941); and there were other minor differences.

This article relating to steam locomotives operated in the United Kingdom is a stub.