2018 Kia Optima Oil Type & Capacity
The 2018 Kia Optima oil type depends on the engine: the 2.0L takes 5W-20 (4.33 quarts qt with filter); the EX takes 5W-20 (5.07 quarts qt with filter); the LX takes 5W-20 (5.07 quarts qt with filter); the LX 1.6T takes 5W-30 (4.75 quarts qt with filter); the Plug-In Hybrid EX takes 5W-20 (4.33 quarts qt with filter); the S takes 5W-20 (5.07 quarts qt with filter); the SX takes 5W-30 (5.07 quarts qt with filter); the SX Limited takes 5W-30 (5.07 quarts qt with filter), per the factory service manual.
Factory-spec answer
It depends on the engine:
- 2.0L: 5W-20, 4.33 quarts with filter
- 2.0L: 5W-20, 4.33 quarts with filter
- 2.0L: 5W-20, 4.33 quarts with filter
- 2.0L: 5W-20, 4.33 quarts with filter
- EX: 5W-20, 5.07 quarts with filter
- LX: 5W-20, 5.07 quarts with filter
- LX 1.6T: 5W-30, 4.75 quarts with filter
- Plug-In Hybrid EX: 5W-20, 4.33 quarts with filter
- S: 5W-20, 5.07 quarts with filter
- SX: 5W-30, 5.07 quarts with filter
- SX Limited: 5W-30, 5.07 quarts with filter
Oil capacity by engine
| Engine | Oil Type (viscosity) | Capacity w/ Filter | Capacity w/o Filter | Notes |
|---|---|---|---|---|
| 2.0L — Hybrid EX, 2.0L Eng VIN C, 2.0L Eng,Gas/Electric | API SM or above, ILSAC GF-4 or above, ACEA-A5 or above, SAE 5W-20, 5W-30 | 4.33 QTS. | — | If the ACEA A5 engine oil is not available in your country, you are able to use API SM or above, ILSAC Gf-4 or above, ACEA A3. |
| 2.0L — Hybrid Premium, 2.0L Eng VIN C, 2.0L Eng,Gas/Electric | API SM or above, ILSAC GF-4 or above, ACEA-A5 or above, SAE 5W-20, 5W-30 | 4.33 QTS. | — | If the ACEA A5 engine oil is not available in your country, you are able to use API SM or above, ILSAC Gf-4 or above, ACEA A3. |
| 2.0L — Hybrid Premium, 2.0L Eng VIN E, 2.0L Eng,Gas/Electric | API SM or above, ILSAC GF-4 or above, ACEA-A5 or above, SAE 5W-20, 5W-30 | 4.33 QTS. | — | If the ACEA A5 engine oil is not available in your country, you are able to use API SM or above, ILSAC Gf-4 or above, ACEA A3. |
| 2.0L — Hybrid EX, 2.0L Eng VIN E, 2.0L Eng,Gas/Electric | API SM or above, ILSAC GF-4 or above, ACEA-A5 or above, SAE 5W-20, 5W-30 | 4.33 QTS. | — | If the ACEA A5 engine oil is not available in your country, you are able to use API SM or above, ILSAC Gf-4 or above, ACEA A3. |
| EX — 2.4L Eng | API Service SM, ILSAC GF-4 or above, SAE 5W-20 or SAE 5W-30 | 5.07 QTS. | — | KIA recommends TOTAL QUARTZ oil. If the API service SM engine oil is not available, you may use API service SL. For better fuel economy, it is recommended to use the engine oil viscosity grade SAE 5W-20 (API SM/ILSAC GF-4). |
| LX — 2.4L Eng | API Service SM, ILSAC GF-4 or above, SAE 5W-20 or SAE 5W-30 | 5.07 QTS. | — | KIA recommends TOTAL QUARTZ oil. If the API service SM engine oil is not available, you may use API service SL. For better fuel economy, it is recommended to use the engine oil viscosity grade SAE 5W-20 (API SM/ILSAC GF-4). |
| LX 1.6T — 1.6L Eng | ACEA A5 or above, SAE 5W-30, 5W-40 | 4.75 QTS. | — | KIA recommends TOTAL QUARTZ oil. If the API service SM engine oil is not available, you may use API service SL. |
| Plug-In Hybrid EX — 2.0L Eng,Gas/Electric | API SM or above, ILSAC GF-4 or above, ACEA-A5 or above, SAE 5W-20, 5W-30 | 4.33 QTS. | — | If the ACEA A5 engine oil is not available in your country, you are able to use API SM or above, ILSAC Gf-4 or above, ACEA A3. |
| S — 2.4L Eng | API Service SM, ILSAC GF-4 or above, SAE 5W-20 or SAE 5W-30 | 5.07 QTS. | — | KIA recommends TOTAL QUARTZ oil. If the API service SM engine oil is not available, you may use API service SL. For better fuel economy, it is recommended to use the engine oil viscosity grade SAE 5W-20 (API SM/ILSAC GF-4). |
| SX — 2.0L Eng,Gas | ACEA A5 or above, SAE 5W-30, 5W-40 | 5.07 QTS. | — | KIA recommends TOTAL QUARTZ oil. If the API service SM engine oil is not available, you may use API service SL. |
| SX Limited — 2.0L Eng,Gas | ACEA A5 or above, SAE 5W-30, 5W-40 | 5.07 QTS. | — | KIA recommends TOTAL QUARTZ oil. If the API service SM engine oil is not available, you may use API service SL. |
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More factory specs & repair guides for your Optima
🛞 2018 Kia Optima Tire Size & Pressure →🌧️ 2018 Kia Optima Wiper Blade Sizes →💡 2018 Kia Optima Light Bulb Sizes →📖 2018 Kia Optima Factory Service Manual →All fluid capacities (transmission, coolant, brakes)Powered by factory manual data from our partner network AllOEMManuals.com.
Coolant capacity
7.12 quarts (6.73 L) — 50/50 mixture of Ethylene Glycol Antifreeze and water
Frequently asked questions
What type of oil does a 2018 Kia Optima take?
It depends on the engine: 2.0L uses 5W-20; EX uses 5W-20; LX uses 5W-20; LX 1.6T uses 5W-30; Plug-In Hybrid EX uses 5W-20; S uses 5W-20; SX uses 5W-30; SX Limited uses 5W-30.
What is the oil capacity of a 2018 Kia Optima?
Oil capacity depends on the engine: 2.0L holds 4.33 quarts with filter; EX holds 5.07 quarts with filter; LX holds 5.07 quarts with filter; LX 1.6T holds 4.75 quarts with filter; Plug-In Hybrid EX holds 4.33 quarts with filter; S holds 5.07 quarts with filter; SX holds 5.07 quarts with filter; SX Limited holds 5.07 quarts with filter.
How often should I change the oil in my 2018 Kia Optima?
Most 2018 Kia Optima owners follow a 5,000–7,500 mile interval with conventional oil, or up to 10,000 miles with full synthetic. Always check the oil life monitor if equipped, and consult your owner's manual — Kia recommends intervals based on driving conditions, not just mileage.
Can I use synthetic oil in my 2018 Kia Optima?
Yes. 5W-20 is widely available as a full synthetic, and synthetic is safe (often recommended) for the 2018 Kia Optima. What matters most is matching the factory viscosity and specification, then changing the oil and filter on schedule.