I have a 1984 Toyota 4x4 with around 184,000 miles that is used for work and play. During every oil change, I substiitute one quart of Castrol with a quart of Lucas Heavy Duty Oil Stabilizer. My wife was driving it home one evening and the oil light came on due to the timing cover seal blowing. She drove it another 4 to 5 miles home and the truck never missed a beat even though there was only 1/2 quart of oil left in the oil pan. I firmly  believe using Lucas saved the engine.

Great products! Thanks!
Dan