Why do we need gear oil?
As you know, lubricants play a vital role in the inner workings of your vehicle, and gear oil is no exception. Your car’s gearbox system engages in a lot of metal-on-metal contact which without the correct lubrication, can result in premature and preventable wear and tear of components. The subsequent repairs will, of course, leave you inconvenienced and out of pocket. Frequent maintenance of your car’s lubricants, including gear oil, is imperative to the smooth running of your vehicle.
What is gear oil and what is it used for?
Gear oil is a lubricant that is designed for use in transmissions, transaxles, transfer cases and differentials in vehicles. The various transmission types on the market, such as manual, automatic, continuously variable and double clutch, have created a requirement for tailored gear oils (or transmission fluids) that must possess a range of characteristics. Each of these gear oils must ensure efficient performance as well as compatibility with all relevant components within each system.
Properties of gear oil
As discussed above, each gear oil application has its own requirements. At a base level, all gear oils must provide sufficient lubrication to prevent wear, corrosion and damage from overheating, as well as aid in the smooth operation of the transmission.
Depending on the transmission type, however, more complex characteristics can be required. For example, gear oils for automatic transmissions must ensure the correct friction when opening and closing the oil-lubricated lamellar clutches and applying brakes. This gets more complex when certain manufacturers have different requirements concerning their coefficient friction characteristics.
Continuously variable transmissions have the added requirement of good foaming and air release properties due to the use of strong hydraulic pumps. The correct gear oil will prevent cavitation in the pump, leading to a longer life of parts.
Gear oil FAQs
Generally speaking, if you drive your vehicle under normal conditions you should change the gear oil in manual transmissions every 30,000 to 50,000 miles. For automatic transmissions, gear oil should be changed every 60,000 to 100,000 miles. It is always advisable to check the owner’s manual, however, as this can differ between vehicles.
Getting your vehicle serviced at the recommended intervals should ensure that lubricant levels and quality are optimal, however, there are a few signs to look out for that could mean your gear oil needs to be changed:
- Gears slipping or slipping out of gear
- Clunky / notchy gear changes
- Whining or grinding noises
- Burning smells
- Dark or gritty oil
- Leaks
It is advisable to check lubricant levels in your vehicle once a month, especially before long drives.
Most gearboxes do not have dipsticks, and the oil level is checked by removing the oil filler plug when the vehicle is on level ground. If the oil level is correct, it should just reach the bottom lip of the hole.
If your gearbox does have a dipstick, follow the steps below:
- Lift your bonnet and locate the gear oil dipstick. This is usually located near the back of the engine compartment.
- Pull out the dipstick and wipe it clean with a cloth, then reinsert the dipstick. Take the dipstick back out and check the oil level. Most dipsticks feature a cross-hatch pattern where the oil level should sit. You may also see hot and cold lines - your oil should never go above the hot line.
- If your oil is running low, top it up with the advised level of gear oil.
Due to the harsh operating conditions, gear oil deteriorates over time and so should be changed at regular intervals to avoid damage to the inner workings of your vehicle.
Transmissions and gear systems present continuous metal-on-metal contact while in operation, which naturally results in tiny metal particles contaminating the gear oil over a period of time. These particles will eventually compromise the lubricating properties of the oil and, as a consequence, damage components in the way of scouring, corroding, scuffing and pitting.
Which gear oil do I need for my vehicle?
It is imperative that you check the manufacturer's specifications when choosing gear oil as using the wrong one can affect the performance of your vehicle, and even cause severe damage to components.
We understand that choosing the correct lubrication for your vehicle can be a complex task.
The > FUCHS Oil Chooser eliminates the guesswork allowing you to find the right product in under 1 minute. Simply enter your vehicle registration plate or make and model to discover lubricants relevant to your specific vehicle.
Alternatively, contact our team using the enquiry form below.
ANY QUESTIONS?
Here at FUCHS UK, our teams of experts are always on-hand to answer any of your questions. With years of experience in automotive lubrication you can trust that you’re in safe and knowledgeable hands.
NEED TECHNICAL HELP?
Speak to our technical team today to learn more about how FUCHS products can help you.