A 1994 Argentine expedition claimed —using GPS technology available at the time— that the elevation of Monte Pissis was , higher than Ojos del Salado. Ten years later, with the use of higher precision systems, several other surveys proved that those measurements were inaccurate: in 2005, an Austrian team performed a DGPS survey of Pissis' summit and found the elevation to be . In 2006 an international expedition surveyed the height on the summit, and found results in agreement with an elevation around . This was later confirmed by a 2007 Chilean-Argentine-European expedition, which surveyed both Ojos del Salado and Monte Pissis and provisionally found the former to be and the latter .