Should I change it?
Not on the normal schedule. Severe use is every 60,000 miles.
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In-depth guide
2021 Hyundai Sonata
2021 Sonata automatic transmission fluid is 6.89 US qt of ATF SP-IV. The normal schedule says no check and no service required.
| Item | Figure |
|---|---|
| Capacity and fluid | 6.89 US qt (6.5 L) of ATF SP-IV, the brands the table names. |
| Normal schedule | No check, no service required. Both engines. |
| Severe schedule | Replace every 60,000 miles. Conditions A, C, E, F, G, and I. |
Source: owner's manual / last verified 2026-10-16 (2021 Hyundai Sonata owner's manual, recommended lubricants and maintenance (opens in a new tab)).
Difficulty, time, and cost are estimates when this guide gives them. Torque is a cited figure, or it is left off.
Main source: 2021 Hyundai Sonata owner's manual, recommended lubricants and maintenance (opens in a new tab), Hyundai Motor America, published 2020-08-20, read 2026-10-16.
Funnel
Only if a severe-service change is actually due. The normal schedule says no service.
| Item | Figure | Where it comes from |
|---|---|---|
| Capacity and fluid | 6.89 US qt (6.5 L) of ATF SP-IV, the brands the table names. | Recommended lubricants and capacities |
| Normal schedule | No check, no service required. Both engines. | Normal maintenance schedule |
| Severe schedule | Replace every 60,000 miles. Conditions A, C, E, F, G, and I. | Maintenance under severe usage |
Capacity is 6.89 US qt of ATF SP-IV. Normal service is no check and no service required.
Replace every 60,000 miles under the conditions the severe chart names.
None is printed.
2021 Sonata Owner's Manual. The PDF title is 2021 Sonata Owners Manual and the file was created August 20, 2020. Engine oil is serviced on a different line: engine oil.
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Part
HYUNDAI genuine ATF SP-IV
Also MICHANG, SK, NOCA, S-oil, or other brands meeting the specification approved by HYUNDAI. 6.89 US qt (6.5 L).
2021 Sonata automatic transmission fluid (opens in a new tab)Search Amazon.com (affiliate link) (opens in a new tab)As an Amazon Associate I earn from qualifying purchases.
Tool
Funnel
Only if a severe-service change is actually due. The normal schedule says no service.
Not on the normal schedule. Severe use is every 60,000 miles.
6.89 US qt (6.5 L).
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