1984 Plymouth Conquest Oil Type & Capacity: 5W-20 (4.5 quarts)
The 1984 Plymouth Conquest takes 5W-20 motor oil — 4.5 quarts with a filter change, per the factory service manual.
Factory-spec answer
5W-20 — 4.5 quarts with filter
Oil capacity by engine
| Engine | Oil Type (viscosity) | Capacity w/ Filter | Capacity w/o Filter | Notes |
|---|---|---|---|---|
| Automatic | API - SAE 5W-20/30/40 (Below 60Deg.F), 10W-30/40/50 (Above 0Deg.F), 15W-40 (Above 10Deg. F), 20W-20 (20Deg.F to 80Deg. F), 20W-40/50/30 (Above 20Deg.F) | 4.50 QTS. | 4.00 QTS. | — |
| Standard | API - SAE 5W-20/30/40 (Below 60Deg.F), 10W-30/40/50 (Above 0Deg.F), 15W-40 (Above 10Deg. F), 20W-20 (20Deg.F to 80Deg. F), 20W-40/50/30 (Above 20Deg.F) | 4.50 QTS. | 4.00 QTS. | — |
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More factory specs & repair guides for your Conquest
🛞 1984 Plymouth Conquest Tire Size & Pressure →🌧️ 1984 Plymouth Conquest Wiper Blade Sizes →💡 1984 Plymouth Conquest Light Bulb Sizes →📖 1984 Plymouth Conquest Factory Service Manual →All fluid capacities (transmission, coolant, brakes)Powered by factory manual data from our partner network AllOEMManuals.com.
Coolant capacity
9.5 quarts (8.99 L) — 50/50 mixture of Ethylene Glycol Base Antifreeze and water
Frequently asked questions
What type of oil does a 1984 Plymouth Conquest take?
The 1984 Plymouth Conquest takes 5W-20 motor oil (API - SAE 5W-20/30/40 (Below 60Deg.F), 10W-30/40/50 (Above 0Deg.F), 15W-40 (Above 10Deg. F), 20W-20 (20Deg.F to 80Deg. F), 20W-40/50/30 (Above 20Deg.F)), per the factory service manual.
What is the oil capacity of a 1984 Plymouth Conquest?
The 1984 Plymouth Conquest oil capacity is 4.5 quarts with a filter change, or 4.0 quarts without changing the filter.
How often should I change the oil in my 1984 Plymouth Conquest?
Most 1984 Plymouth Conquest 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 — Plymouth recommends intervals based on driving conditions, not just mileage.
Can I use synthetic oil in my 1984 Plymouth Conquest?
Yes. 5W-20 is widely available as a full synthetic, and synthetic is safe (often recommended) for the 1984 Plymouth Conquest. What matters most is matching the factory viscosity and specification, then changing the oil and filter on schedule.