In 1925 the third Le Mans Grand Prix d'Endurance took place and S.T.D. entered two Sunbeam Super Sport one for Jean Chassagne and Sammy C H Davis, the other for H.O.D. Segrave and G Duller.
For the 1926 Le Mans Grand Prix d'Endurance Chassagne was entered with an Aries Surbaissée 2ltr car; further races with Aries Surbaissée continued in 1927 achieving excellent results in endurance racing in Belgium, France and Spain.