What transmission fluid does a 2018 Subaru Impreza take?
The fluid you need depends on which transmission your car has: CVT models require Subaru CVT Fluid HT, while manual-transmission models use SAE 75W-90 GL-4 gear oil.
Overview of the 2018 Impreza transmissions
The 2018 Impreza could be equipped with either a Lineartronic CVT or a 5-speed manual, depending on trim level. Each transmission type has its own specific fluid requirements, and using the wrong fluid can cause performance issues or damage.
CVT (Lineartronic) transmission
Before listing the fluid, note that the CVT requires a fluid formulated specifically for Subaru’s belt-driven transmission.
- Use Subaru CVT Fluid HT (High Temperature), as specified by Subaru for the Lineartronic CVT.
- Do not use conventional automatic transmission fluid (ATF), engine oil, or other gear oils in the CVT.
- Follow the maintenance schedule and fill procedures in the owner's manual or as advised by a Subaru dealer.
The CVT fluid HT is designed to handle the heat and unique hydraulic needs of Subaru’s Lineartronic system. Using the wrong fluid can lead to poor performance or transmission damage.
5-speed manual transmission
If your 2018 Impreza has the manual transmission, the correct fluid is different from the CVT fluid.
- Use SAE 75W-90 GL-4 gear oil for the manual transmission.
- Avoid GL-5 gear oils unless explicitly approved by Subaru for this transmission.
- Consult the owner's manual for the exact fill procedure and level check.
Using the proper manual transmission fluid is essential for smooth shifting and to protect the synchronizers and gears over time.
Why fluid choice matters
Subaru designs its CVT and manual transmissions to operate with specific fluids. Substituting fluids or using the wrong grade can cause slipping, overheating, wear, or transmission failure, and may void warranties. When in doubt, consult the owner's manual or a Subaru-certified technician.
What to do if you're unsure which transmission you have
Check the vehicle’s trim, VIN, or documentation to confirm whether your car has the CVT or the manual transmission. If you're uncertain, contact a Subaru dealer or a trusted mechanic before buying or changing transmission fluid.
Summary
In brief: the 2018 Impreza’s transmission fluid depends on the transmission type. CVT models use Subaru CVT Fluid HT, while manual models require SAE 75W-90 GL-4 gear oil. Always follow the owner’s manual or dealer guidance, and avoid mixing fluids or using incorrect formulations to protect transmission life.
