Mobil Delvac 1 Transmission Fluid MBT is formulated with an advanced additive system providing excellent thermal stability and wear resistance. Mobil Delvac 1 Transmission Fluid MBT maintains lower temperatures in the transmission compared to conventional transmission oils. It is recommended for most manual transmissions, transaxles and mild hypoid axles where an API GL-5 oil is not required. Mobil Delvac 1 Transmission Fluid MBT is suited for use in transmissions (gearboxes) where lubricants are exposed to very high temperatures under full-load service.