They saw occasional service on the then under-used Auckland suburban passenger network where they performed well, but NZR focused them on their intended purpose, heavy shunting. In the late 1980s, NZR provided a DH locomotive to the Tasman Pulp and Paper mill in Kawerau to trial for sale as a heavy shunter in the mill's rail yards.
They occasionally operated on Auckland's suburban passenger network, where they were effective; but NZR redirected their focus toward their primary function, heavy shunting. In the late 1980s, NZR supplied a DH locomotive to the Tasman Pulp and Paper mill in Kawerau for testing as a possible heavy shunter in the mill's rail facilities.