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The casual motorist may think that 'oil is oil' when it comes to different types of lubrication. However, that's far from the case, as the major mechanical components require completely different types of oil in order to lubricate safely and efficiently. The oil used in the vehicle's manual gearbox is very different from that found in the engine or any automatic transmission.



What is Gear Oil

  • Gear oil is specially formulated for the often-violent action found when two shafts come into contact with each other via the gears. Whenever a driver goes through a range of gears during acceleration, friction is generated each time the clutch engages and disengages and different gears mesh with each other in order to regulate the power provided by the engine. Without carefully engineered gear oil, damage would invariably be caused to those components.

How Does Gear Oil Work?

  • Gear oil is higher in viscosity than engine oil and sticks to moving parts to ensure crucial gear lubrication.The constant "clash" of mechanical parts can build up friction and heat, and gear oil is specially formulated to withstand high temperatures. Manufacturers also include special additives, especially where a hypoid gear is fitted,to keep pressure under control.

How Is Gear Oil Made?

  • The base product is derived from refined crude, before important additives are introduced.These additives are specific to the type of gearbox and the components found within,because certain additives contain compounds that are corrosive to internal synchronizers. Additives help with excess wear and pressurized operation.

How Does Gearbox Oil Fail?

  • It can become contaminated by moisture.
  • It can lose its viscosity.

What are Symptoms of Failure?

  • Difficulty in engaging gear.
  • Presence of tiny flakes of metal in the oil or discoloration.

What Are the Consequences of Failure?

  • Damage to the gearbox.

When the right type of gear oil is used with the correct viscosity and carefully chosen additives, gear oil can last for a significant amount of time. However, it's important to monitor the level and look for discoloration or metal shavings by checking the oil periodically.

If you have questions or concerns about gear oil or any of your vehicle’s components or fluids, come into your local Pep Boys where we can answer any question, help you find any part, or perform any vehicle service you might need.