BG Pre-Lube is a smooth, tenacious lubricant combined with anti-scuff, anti-wear additives specially designed for engine, transmission and parts assembly. Under stress conditions, ingredients in BG Pre-Lube have the effect of smoothing and sealing the surfaces of metal components. Even the finest metal finish in newly assembled engines is microscopically rough; thus, all new parts should be treated with BG Pre-Lube before assembly.