A spinline viscometer was used to measure the apparent extensional viscosity of eight motor oils consisting of two SAE grades at two different temperatures. Oils corresponding to a 5W30 grade appeared to be slightly more elastic than 10W40 oils in extension. However, none of the oils was very elastic; measured Trouton ratios were less than 20 in each case. In fact, the 10W40 oils exhibited Newtonian behavior at low stretch rates. All the oils became slightly less elastic as the temperature of measurement was raised. In addition, an oil formulated using a synthetic base stock was found to behave differently from oils containing solvent extracted or hydrotreated base stocks.