 Although the J class produced the same nominal tractive effort as the K or N class, they had a slightly higher adhesive weight (and as such a better factor of adhesion) and were permitted to haul heavier loads on gradients.They could be found in goods service on branch lines across the state, but were also found on mainlines running roadside goods services.However, within a year of the J's introduction, the T class diesel electric locomotive was also introduced.