I am getting the other Suburban. Previous owner saw large wet spots under the back side of the engine and on the ground and was told that the rear main seal was shot and to just keep plenty of oil in it... It is 2 quarts over right now, and no significant oil leakage. I crawled under it while it was running and gas is spraying from a tiny hole that was rubbed through the stainless high pressure line from the tank by a small bracket that was not secured to the body. Think I found the "oil leak". Gonna patch it and drive it home this weekend.