For the 1980 Oldsmobile 88 equipped with the 5.7L 8-cylinder Diesel (Engine Code N), the engine oil capacity is 7 quarts when replacing the filter. Recommended viscosities include 10W-30 for temperatures below 16°C, 15W-40 for -18 to 16°C, and SAE 30 is preferred for temperatures above 0°C. AMSOIL recommends using their Signature Series or Heavy-Duty synthetic diesel oils for superior wear protection.
What oil does a 1980 Oldsmobile 88 5.7L Diesel take?
The 1980 Oldsmobile 88 with the 5.7L V8 diesel engine requires an oil grade of CF. Depending on your operating environment, you should select a viscosity that matches your ambient temperature to ensure proper lubrication and protection.
AMSOIL product recommendations
Based on the vehicle specifications, AMSOIL provides several high-performance lubrication options to maintain engine and transmission health.
Engine Oil Recommendations
| Product Name | Viscosity | Part Number |
|---|---|---|
| AMSOIL Signature Series 10W-30 100% Synthetic Max-Duty Diesel Oil | 10W-30 | DTTQT-EA |
| AMSOIL 10W-30 Heavy-Duty 100% Synthetic Diesel Oil | 10W-30 | ADNQT-EA |
| AMSOIL Signature Series 5W-30 100% Synthetic Max-Duty Diesel Oil | 5W-30 | DHDQT-EA |
Oil Filter Recommendation
| Product Name | Part Number |
|---|---|
| AMSOIL Oil Filter | EAO64-EA |
Coolant & Antifreeze Recommendations
| Product Name | Part Number |
|---|---|
| AMSOIL Passenger Car & Light Truck Antifreeze & Coolant | ANTPC1G-EA |
| AMSOIL Propylene Glycol Antifreeze and Engine Coolant | ANT1G-EA |
Automatic Transmission Fluid Recommendations
| Product Name | Part Number |
|---|---|
| AMSOIL Signature Series Fuel-Efficient 100% Synthetic ATF | ATLPK-EA |
| AMSOIL OE Fuel-Efficient 100% Synthetic ATF | OTLQT-EA |
Engine Oil Viscosity Specifications
| Temperature Range | Recommended Viscosity |
|---|---|
| Below 16°C | 10W-30 |
| -18 to 16°C | 15W-40 |
| Above 0°C | SAE 30 (Preferred) |
Engine Oil Capacity and Torque
| Description | Specification |
|---|---|
| Oil Capacity (with filter) | 7 quarts |
| Oil Drain Plug Torque | 30 ft/lbs |
Note: Always check the oil level after refilling.
Automatic Transmission Fluid Specifications
The transmission requirements vary based on your specific model (THM350C, THM350, THM200C, or THM250C). Note that manufacturer technical service bulletins have updated the specification from Dexron II or III to Dexron VI for these applications.
Transmission Capacity and Type
| Transmission Model | Total Fill Capacity | Initial Fill |
|---|---|---|
| THM350C (3-speed) | 10 quarts | 3 quarts |
| THM350 (3-speed) | 10 quarts | 3 quarts |
| THM200C (3-speed) | 9.4 quarts | 3.5 quarts |
| THM250C (3-speed) | 10.8 quarts | 4 quarts |
Diesel maintenance notes for this vehicle
Maintaining a vintage diesel engine requires attention to detail. For the 1980 Oldsmobile 5.7L Diesel, focus on the following:
- Oil Level: Always verify the oil level after every refill.
- Cooling System: Ensure the cooling system is maintained with appropriate antifreeze to protect metals and gaskets.
- Filter Maintenance: Use high-efficiency filters like the AMSOIL EAO64-EA to capture small, wear-causing contaminants.
Common diesel oil-related concerns and how AMSOIL products may help
| Concern | Why it matters | AMSOIL Product | How it may help | Limitation |
|---|---|---|---|---|
| Engine Wear | Diesel engines face high pressure and friction. | Signature Series Diesel Oil | Delivers up to 6X more wear protection. | Requires regular monitoring. |
| Extreme Temperatures | Viscosity changes can affect lubrication. | Heavy-Duty Synthetic Diesel Oil | Excels in extreme temperatures. | Not confirmed from source data. |
| Contaminants | Small particles cause engine damage. | AMSOIL Oil Filter (EAO64-EA) | 99% efficiency at 20 microns. | Not confirmed from source data. |
Common maintenance concerns for this vehicle
Based on historical research, owners of the 1980 Oldsmobile 5.7L V8 diesel should prioritize:
- Cooling System Integrity: Maintaining proper coolant levels and quality is vital.
- Fuel System Cleanliness: Diesel engines are sensitive to fuel quality.
- Head Gasket Durability: This engine family has historically faced challenges in this area.
Note: Maintenance research should focus on these areas, but specific part compatibility must be verified with a specialist as diesel components differ from gasoline versions.
Recall, TSB, and manufacturer communication notes
NHTSA recall research for the 1980 Oldsmobile 88 identified two campaigns:
- Seat Belt Anchorage (79V247000): Front outboard seat belt anchor bolts may break due to high installation torque and arrangement. Dealers were instructed to replace these bolts at no cost.
- Tire Placard Labels (79V229000): The tire placard did not contain recommended tire size information, failing to comply with Federal Motor Vehicle Safety Standard No. 110.
Always verify open recalls by VIN through an authorized dealer or the NHTSA website.
About this vehicle
The 1980 Oldsmobile 88 with the 5.7L V8 diesel engine represents a specific era in General Motors’ history when the company attempted to capture the burgeoning diesel market for passenger cars. The Oldsmobile 88 has been a staple of the Oldsmobile lineup since 1949, historically utilizing various iterations of the ‘Rocket’ V8 architecture.
The 350 cu in (5.7 L) V8 diesel engine was produced by General Motors between 1978 and 1985. It was designed using the existing Oldsmobile 350 gasoline engine architecture as a foundation. While intended to provide fuel economy for full-size vehicles, this specific V8 variant is historically noted for significant reliability challenges that impacted the reputation of American light diesel passenger cars during this period.
Because this engine/model combination is subject to well-documented historical reliability issues, maintenance research should focus heavily on cooling system integrity, fuel system cleanliness, and head gasket durability. Owners often find themselves researching specialized diesel components that differ significantly from the gasoline ‘Rocket’ V8s used in other Oldsmobile models. It is highly recommended that owners verify exact part compatibility with a specialist, as many parts are not interchangeable with standard gasoline small-block engines.
Common questions about this vehicle’s diesel oil and maintenance
What is the oil capacity for my 1980 Oldsmobile 88 Diesel?
The capacity is 7 quarts when including a filter change. Always check the level after refilling.
Which viscosity should I use for cold weather?
For temperatures below 16°C, 10W-30 is recommended. For temperatures between -18 and 16°C, 15W-40 is suggested.
How much transmission fluid does the THM350C take?
The total fill capacity for a 3-speed THM350C is 10 quarts, with an initial fill of 3 quarts.
Can I use Dexron II or III in my transmission?
The AMSOIL lookup note references that the specification has been updated from Dexron II or III to Dexron VI per a manufacturer Technical Service Bulletin.
What is the torque spec for the oil drain plug?
The oil drain plug should be torqued to 30 ft/lbs.
How often can I extend my oil change intervals?
Using products like AMSOIL Signature Series Max-Duty Diesel Oil is designed to help you confidently extend drain intervals.
Disclaimer: Not all information provided is from the manufacturer. Always consult your owner’s manual or a certified mechanic before performing maintenance.