Despite his retirement from full-time racing, Dumbrell returned in a limited basis from 2012 onwards as a co-driver for the two-driver endurance races in V8 Supercars, the Sandown 500, Bathurst 1000 and since 2013, the Gold Coast 600.
Despite his retirement from full-time racing, Dumbrell returned in a limited basis for 2012 in order to comply with V8 Supercar regulations on drivers for the endurance races. Dumbrell currently serves as Jamie Whincup's co-driver for Triple Eight Race Engineering for the V8 Supercars endurance races; the Sandown 500, Bathurst 1000 and since 2013, the Gold Coast 600.