The GER used
air brakes but, when introduced, more than half the T26 locomotives were additionally fitted with
vacuum brake ejectors for operating over the lines of other railway companies. The T26s were assigned to all the major GER sheds for a wide variety of duties and thus travelled widely. The arrival of more modern
4-4-0 types (themselves displaced from main line express work by new-build
LNER locomotives) led to the T26s (classified as E4s by the LNER) being more predominantly used on branch and local passenger duties in the 1920s, and withdrawals began in 1926. In the 1930s six E4s were allocated to the former
North Eastern Railway to work passenger services on the difficult, steeply-graded line between
Darlington and
Penrith over
Stainmore Summit - the highest railway summit in England. The NER 4-4-0s used for many years on the route had been retired and various types had been tried as replacements but none had proven suitable. A single E4 was allocated to the line in 1935 and proved very successful. By 1936 five more were in use and all had their cabs modified with solid cab sides and windows rather than the original open sides to offer better protection from the weather on the exposed upland route. Withdrawals were halted during the
Second World War and twenty four (of the original 100) E4s were in service at the formation of
British Railways in 1948. The introduction of new light
BR Standard locomotives, specifically the
BR Standard Class 2 moguls, followed by
diesel multiple units on many of the rural lines worked by the remaining E4s, led to rapid withdrawal of nearly all the remaining examples between 1954 and 1957 with a single E4, No. 62785, surviving until 1959. The E4s on the Stainmore line were withdrawn in 1957, replaced by DMUs. ==Accidents and incidents==