In 1957 the TR3 had a small update to what is known as the TR3 A, although this was never an official name to the series, it did have some changes from the older production. Differences included a full width radiator grill, exterior door-handle, lockable booth and full toolkit came standard. As for mechanics it was identical to its sibling, still with the 2L 95hp engine. The TR3 A has been the third best-selling Triumph after the TR6 and TR7.