• Synthetic manual transmission fluid is a relative newcomer to the automotive scene. Being comprised purely out of synthetic ingredients, it has shown itself to be remarkably better in most applications than standard organic transmission fluid. Many more automotive manufacturers and drivers are making the swap to reap the benefits that can improve an automobile's performance and durability.
  
  

Friction Reduction

• According to Exxon Mobil Corporation, synthetic manual transmission fluids provide a significant reduction in the amount of gearbox friction over standard sulfur-phosphorus-based fluids. This allows for an improvement in overall fuel economy, as well as a reduction in operating costs associated with internal parts damaged by friction.
  
  With this reduction in friction comes a significant improvement in cold weather shifting ability. Many manual transmissions being operated in extreme environments will be easier to engage and shift with synthetic manual transmission fluid in use.
  
  

Rust Protection

• Synthetic manual transmission fluid has properties that allow for a reduction in the amount of rust and corrosion typically found in transmission cases. Typical sulfur-phosphorous mineral fluids can cause a significant amount of rust and other types of deposits, which can lead to a weakening of internal gearbox parts. Synthetic fluids will remove much of that risk, preserving your transmission for however long you plan to own your vehicle.
  
  

Thermal Stability

• Synthetic manual transmission fluids are specifically designed not to break down under extreme temperature variations. For example, AMSOIL synthetic manual transmission fluid is shown to maintain its design viscosity between -40 degrees Fahrenheit and 300 degrees Fahrenheit. This ensures that even under extreme hot and cold temperatures, the transmission will continue to work as it was designed. This is a drastic improvement over standard mineral fluids, which are unable to handle such a wide temperature variation.
  
  Along with allowing the transmission to operate effectively in harsh environments, synthetic manual transmission fluids have the ability to protect the gears and bearings from damage when operating under extreme high or low temperatures.
  
  

Warranty Coverage

• Automobile owners interested in making a switch to synthetic fluid need not worry about voiding their car's warranty. Many automobile manufacturers lay out specific types of fluids that are approved for use in their cars. According to the Exxon Mobile Corporation, its synthetic manual transmission fluids meet the warranty requirements of many automotive manufacturers. AMSOIL also claims to meet those requirements with its line of transmission fluids, particularly those requirements laid out by General Motors, Honda and Chrysler.