My parents just bought a 2003 Numar motorhome that has a -gas- '03 GM 8.1L Vortec in it with the Allison tranny. I am trying to figure out what oil would be best to run in it. I searched and came across -THIS- thread whom some seem to recommend a good heavy duty oil like 5w40 Delvac/Rotella. He ran Schaeffer's oil in his last motorhome (Chev 454) and liked it and was thinking about running it in his new one with the 8.1L Vortec as well. Would -SCHAEFFER'S SUPREME 9000 5w40- be a good choice for this engine??
thanks!
Paul
thanks!
Paul