On 21 December 2016, KiwiRail announced their plan to withdraw from service, over a two-year period, the EF class electric locomotives (the only electric rolling stock working the central electrified section) without replacing them. The reasons given for the decision included the fact that the EFs are now close to their end of life (approximately 30 years old) and suffer from frequent breakdowns (on average every which is well below the expected breakdown-free service interval of ) and that having to change from a diesel locomotive to an electric one and back again at each end of the electrified section is labour-intensive, time-consuming and adds to costs. KiwiRail did not intend to de-electrify the section but would maintain it so that electric rolling stock could be reintroduced in the future.