Why Teslas Have Oil Filters (Even Though They Don't Use Engine Oil)

When you think about Tesla's electric vehicles (EVs), maintenance is the last thing to come to mind, knowing that they don't rely on internal combustion to run. Many would-be Tesla owners even assume that they can save a lot on regular maintenance since the vehicles are battery-powered and don't have traditional engine components like pistons, bearings, and valves. Though this is true, Teslas still need maintenance — just not as often or as much as their gasoline- or diesel-powered counterparts.

Tesla, which  became the best-selling luxury car brand in the United States in 2023, offers some advantages to first-time EV owners. Without spark plugs, emissions systems, and fuel tanks, Tesla vehicles are free from some of the problems of internal combustion engine cars. Visits to a service facility are also minimized by remote diagnostics and software upgrades. However, while Tesla has done away with fossil fuel combustion and many traditional car parts, there's one thing they couldn't fully eliminate from their EV offerings — oil. Every Tesla vehicle depends on electric motors and modified drivetrains in the absence of standard piston engines, but they still need oil and oil filters to function. But instead of lubricating the internal components of the engine, a Tesla oil filter is mounted on the gearbox, or drive unit. 

In an April 2020 teardown video from car parts expert Munro and Associates, host Sandy Munro explained how the Tesla drive units are lubricated. "It's not really a transmission, it's more like a gearbox, and a gearbox would use oil, not transmission fluid. So, this is a little filter that makes sure that the oil that's rushing around doesn't choke any of the little components stuck inside the motor and the gearbox,"  Munro explained. 

Tesla's drive unit oil filters are similar to engine oil filters like the one pictured above. However, it's noteworthy that Tesla's gearbox is different from those found in traditional cars, with just a single gear ratio instead of a multi-gear setup. Since it still comes with rotating enmeshed parts, lubrication is needed, and this explains the need for oil and an oil filter. This information may not be as important as the 10 things you should know before buying a Tesla, but it is critical to know once that purchase has been made.

Tesla's various models have commonalities and differences. However, the Model 3, Model S, Model X, and Model Y all come with gearbox filters. Two wheel drive models only have one filter, while all wheel drive models have two: one on the rear drive unit and another on the front. Similar to standard oil filters, they need regular replacement to maintain optimum performance on the road. Tesla recommends synthetic gearbox oil for the drive units in its EVs, so it should last longer than conventional lubricants.

The company recommends changing the gearbox oil every two years or 100,000 miles depending on model. In comparison, most cars need an oil change at least once every 10,000 miles.  After draining the gearbox fluid under your Tesla, it is strongly advised to replace the oil filter with a new one regardless if it has visible signs of corrosion or leaks. The process of removing the old oil filter, draining the fluid, and putting a new filter and oil is explained in detail in every Tesla Model's service manual. However, due to the complexity of the process compared to regular oil and filter changes, you might want to have your Tesla drive unit oil and filter changed by a professional mechanic.