The oil filter you need depends on your exact engine; identify the engine variant (2.4L Nu I4 or 2.0L turbo GDI) and use the filter specified by Kia for that engine. In practice this means either a cartridge-style oil filter inside a housing or a traditional spin-on filter, depending on the model's configuration.
To figure out which one you have, check the owner's manual, inspect the current filter, or use Kia's official parts lookup with your Vehicle Identification Number (VIN). Using the correct filter helps ensure proper oil flow and engine protection.
Engine options for the 2015 Optima
The 2015 Optima was offered with two main gasoline engines, and each uses a different oil filter design. Knowing which engine you have will guide your filter choice and installation steps.
- 2.4-liter Nu I4 engine
- 2.0-liter turbocharged GDI engine
Identifying your engine variant is the key first step to selecting the right filter.
Oil filter styles and how to identify yours
As of 2015, Kia Optima engines used either a cartridge-style filter inside a housing or a traditional spin-on filter, depending on the exact engine configuration. The following sections help you identify which style your car uses.
Cartridge-style oil filter (housing)
This design uses a cartridge element inside a reusable housing with a removable cap. Replacing only the cartridge is common, and you may need a cap wrench to unthread the housing cap. This style is common with several 2.4L Nu-based configurations and many 2.0T variants.
Spin-on oil filter
Some variants used a traditional spin-on filter that screws onto the engine block. It is removed and replaced as a single unit with a gasket seal.
To be sure, verify by checking the existing filter or the official parts diagram for your exact VIN.
Choosing the right filter: OEM vs aftermarket
When selecting a filter, you can opt for Kia Genuine (OEM) filters or reputable aftermarket equivalents that meet OEM specifications for fit, thread size, and gasket diameter. The key is to match the filter to your engine design and the correct oil specification.
- Kia Genuine Oil Filter (OEM)
- Reputable aftermarket options (Bosch, Mann-Filter, Wix, Purolator, etc.) that specify compatibility with the 2015 Optima
- Ensure the selected filter matches the cartridge or spin-on design required by your engine
Choosing the right filter protects oil pressure, minimizes leaks, and maintains warranty compliance when using an OEM or certified aftermarket part.
How to replace the oil filter on a 2015 Optima
If you plan to perform the oil change yourself, follow these general steps to replace the oil filter safely and correctly. This guide assumes you are using the appropriate filter for your engine design.
- Warm the engine, then safely raise and support the vehicle. Position a drain pan beneath the oil pan.
- Remove the drain plug and let old oil drain completely.
- Access the oil filter housing or the spin-on filter. For cartridge-style filters, remove the housing cap and pull out the cartridge; for spin-on, unscrew the filter from its mount.
- Install the new filter: for cartridge-style, insert a new cartridge into the housing and replace the cap; for spin-on, screw on the new filter and tighten to the manufacturer’s torque.
- Replace the oil drain plug seal/gasket if recommended, then refill with the correct amount and viscosity of oil as per the owner's manual.
- Run the engine for a few minutes, check for leaks, turn off, and recheck the oil level, topping up if necessary.
Note: Always follow the exact torque specs and procedures in the owner's manual or service manual, and dispose of used oil and filters properly.
Summary
For a 2015 Kia Optima, the correct oil filter depends on your specific engine variant. Identify whether you have the 2.4L Nu I4 or the 2.0L turbo GDI to determine if your model uses a cartridge-style filter in a housing or a traditional spin-on filter. Use Kia Genuine or a reputable aftermarket filter that meets OEM specifications, and follow proper replacement procedures. When in doubt, consult the dealer or a trusted mechanic to confirm the exact filter and torque requirements for your VIN.