RED LINE Synthetic Manual Transmission Lubricant MTL 75W-80 GL4


Learn More

RED LINE Synthetic Manual Transmission Lubricant MTL 75W-80 GL4

This product has recently changed viscosity grade from 70w-80 to 75w-80.

RED LINE MTL and MT-90 are designed to provide excellent protection and improved shiftability for manual transmissions and transaxles. MTL and MT-90 have cured the problem of hard shifting in numerous transmissions which have notoriously difficult shifting.

The secret to their success is two-fold. First, they have the appropriate coefficient of friction for most manual transmission synchronizers. Many gear oils, engine oils, and ATFs are too slippery for proper synchro engagement. Secondly, the viscosity characteristics of MTL and MT-90 allow proper shifting over the entire temperature range which the transmission will experience. The synthetic base oils used have a very high viscosity index which provides relatively constant viscosity as temperature changes. MTL is a low 75W, almost a 70W, at very low temperatures and a high 80W, nearly an 85W, at elevated temperatures, providing adequate viscosity to prevent wear and deaden gear noise. 


• Eliminates notchy shifting

• Designed for manual transmissions and transaxles

• Perfect synchroniser coefficient of friction

• Enables high-speed downshifting

• Excellent shifting even when cold

• Eliminates gear whine and rattle at high temperatures

• High-performance gear protection

• Non-corrosive toward synchronisers

• Satisfies manual transmissions and transaxles requiring motor oils, or GL-1, GL-3, or GL-4 gear oils

• Compatible with petroleums and other synthetics

• Excellent for high- and low-mile transmissions


  • Satisfies the gear oil viscosity requirements of 75W, 80W, and motor oil viscosities of SAE 30, 10W30 and 5W30
  • Recommended for GL-1, GL-3 and GL-4 applications as well as where most special synchromesh fluids are specified

Recommended For:







Not for use in M41/410 or M46 overdrive gearboxes

UK shipping only