The new Fowler product was announced in early 1948 as the 'Fowler Marshall Diesel Crawler Tractor Mark V.F.'.
Then in 1956 they started selling their new model, the Track-Marshall, which was a crawler fitted with a Perkins L4 four cylinder diesel of 48hp.
Also new was the Fowler Challenger Mk 2 with a Leyland six-cylinder 60hp diesel engine.
Fowler also produced the Challenger range of tracked tractors at the same time.
Track Marshall models were produced with increasing power over the years, and then when the business was sold to British Leyland in 1972, the models were continued branded as Aveling-Marshall.