zMax transmission formula boosts performance at an incredibly cheap price. The 6-ounce bottle may be small, but it can be used for both automatic and manual gears. zMax was designed to reduce leaks and varnish as well. Fluid loss happens due to the presence of road debris and heat within the system and this is far from favorable. Varnish buildup is also a nuisance and can easily wreak havoc on the gears, which is why applying an additive like zMax is necessary. The formula can be used in modern cars without a problem but is not compatible with CVT transmissions.