I am writing to express my appreciation for your product.  I own a 1999 GMC Yukon. Ever since about 180,000 miles I have been using a quart if your oil stabilizer vith 4 quarts of Valvoline at each and every oil change. It now has 420,000 miles and shows no sign of giving up. Original motor and I only have to add any oil between change if I get past 3,000 miles. I belive your oil stabilizer is a big part of the reason this vehicle is still going strong! Thanks! And my hats off to the Lucas NHRA racing team.

Doug Mattson