BARDAHL ALL-U-NEED! NoSmoke + StopLeak is a double-action synthetic formula that treats both problems. First, a chemical solution reduces oil burning and decreases exhaust smoke by "filling-in" the loose tolerances between the moving parts inside an engine. The extra thick formula is very effective in sealing the spaces between the valves and guides, piston rings and cylinder walls. Second, a seal swell agent restores pliability of the seals, which stops any oil leaks. In addition, this solution reduces friction, cushions worn bearings, quiets noisy lifters, improves compression and maintains efficient lubrication to improve the operation of the vehicle.