1985 Buick Somerset Regal Oil Type & Capacity
The 1985 Buick Somerset Regal oil type depends on the engine: the Base, 2.5 U, Automatic takes 5W-30 (3.0 quarts with filter); the Base, 2.5 U, Standard takes 5W-30 (3.0 quarts with filter); the Base, 3.0 L takes 5W-30 (4.0 quarts with filter); the Custom, 2.5 U, Automatic takes 5W-30 (3.0 quarts with filter); the Custom, 2.5 U, Standard takes 5W-30 (3.0 quarts with filter); the Custom, 3.0 L takes 5W-30 (4.0 quarts with filter); the Limited, 2.5 U, Automatic takes 5W-30 (3.0 quarts with filter); the Limited, 2.5 U, Standard takes 5W-30 (3.0 quarts with filter); the Limited, 3.0 L takes 5W-30 (4.0 quarts with filter), per the factory service manual.
Factory-spec answer
It depends on the engine:
- Base, 2.5 U, Automatic: 5W-30, 3.0 quarts with filter
- Base, 2.5 U, Standard: 5W-30, 3.0 quarts with filter
- Base, 3.0 L: 5W-30, 4.0 quarts with filter
- Custom, 2.5 U, Automatic: 5W-30, 3.0 quarts with filter
- Custom, 2.5 U, Standard: 5W-30, 3.0 quarts with filter
- Custom, 3.0 L: 5W-30, 4.0 quarts with filter
- Limited, 2.5 U, Automatic: 5W-30, 3.0 quarts with filter
- Limited, 2.5 U, Standard: 5W-30, 3.0 quarts with filter
- Limited, 3.0 L: 5W-30, 4.0 quarts with filter
Oil capacity by engine
| Engine | Oil Type (viscosity) | Capacity w/ Filter | Capacity w/o Filter | Notes |
|---|---|---|---|---|
| Base, 2.5 U, Automatic — 2.5L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 3.00 QTS. | — | — |
| Base, 2.5 U, Standard — 2.5L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 3.00 QTS. | — | — |
| Base, 3.0 L — 3.0L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 4.00 QTS. | — | — |
| Custom, 2.5 U, Automatic — 2.5L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 3.00 QTS. | — | — |
| Custom, 2.5 U, Standard — 2.5L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 3.00 QTS. | — | — |
| Custom, 3.0 L — 3.0L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 4.00 QTS. | — | — |
| Limited, 2.5 U, Automatic — 2.5L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 3.00 QTS. | — | — |
| Limited, 2.5 U, Standard — 2.5L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 3.00 QTS. | — | — |
| Limited, 3.0 L — 3.0L Eng | SAE 5W-30 (60Deg.F to Below -20Deg.F) 10W-30 (Preferred) or 10W-40 (0Deg.F to Above 100Deg.F), 15W-40 (15Deg.F to Above100Deg.F), 20W-20, 20W-40 or 20W-50 (20Deg.F to Above 100Deg.F), 30 (40Deg.F to Above 100Deg.F) | 4.00 QTS. | — | — |
Buy the right oil
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More specs & repair guides for your Somerset Regal
1985 Buick Somerset Regal factory service manualAll fluid capacities (transmission, coolant, brakes)Powered by factory manual data from our partner site AllOEMManuals.com.
Coolant capacity
5.0 quarts (4.73 L) — 50/50 mixture of Ethylene Glycol Base Antifreeze and water. GM Specification 1825-M.
Frequently asked questions
What type of oil does a 1985 Buick Somerset Regal take?
It depends on the engine: Base, 2.5 U, Automatic uses 5W-30; Base, 2.5 U, Standard uses 5W-30; Base, 3.0 L uses 5W-30; Custom, 2.5 U, Automatic uses 5W-30; Custom, 2.5 U, Standard uses 5W-30; Custom, 3.0 L uses 5W-30; Limited, 2.5 U, Automatic uses 5W-30; Limited, 2.5 U, Standard uses 5W-30; Limited, 3.0 L uses 5W-30.
How much oil does a 1985 Buick Somerset Regal take?
Capacity depends on the engine: Base, 2.5 U, Automatic holds 3.0 quarts with filter; Base, 2.5 U, Standard holds 3.0 quarts with filter; Base, 3.0 L holds 4.0 quarts with filter; Custom, 2.5 U, Automatic holds 3.0 quarts with filter; Custom, 2.5 U, Standard holds 3.0 quarts with filter; Custom, 3.0 L holds 4.0 quarts with filter; Limited, 2.5 U, Automatic holds 3.0 quarts with filter; Limited, 2.5 U, Standard holds 3.0 quarts with filter; Limited, 3.0 L holds 4.0 quarts with filter.
Can I use synthetic oil in my 1985 Buick Somerset Regal?
Yes. 5W-30 is widely available as a full synthetic, and synthetic is safe (often recommended) for the 1985 Buick Somerset Regal. What matters most is matching the factory viscosity and specification, then changing the oil and filter on schedule.