For the 1985 Mercedes Benz 300td with the 3.0L 5-cylinder diesel engine (Code 2998cc), the oil capacity is 8.3 quarts with a filter change. Recommended viscosities include 0W-30 or 0W-40 for all temperatures, 10W-40 for temperatures above -20°C, and 5W-30, 5W-40, or 5W-50 for temperatures above -25°C. AMSOIL recommends using AMSOIL 5W-40 FS 100% Synthetic European Motor Oil or AMSOIL 0W-40 FS 100% Synthetic European Motor Oil for optimal protection.
What oil does a 1985 Mercedes Benz 300td take?
The 1985 Mercedes Benz 300td requires an engine oil with the AMSOIL lookup oil grade SEO41. Depending on your operating environment, you should select a viscosity that matches your local temperature ranges to ensure proper lubrication during startup and high-load operation.
The engine oil capacity is 8.3 quarts when performing a service with the filter. If your model is equipped with an oil cooler, additional oil may be required if the cooler is drained during service. Always allow 5 minutes after refilling or turning the engine off before checking the oil level.
AMSOIL product recommendations
Based on the AMSOIL lookup data, here are the recommended products for your 1985 Mercedes Benz 300td:
| Component | Product Name | Part Code |
|---|---|---|
| Engine Oil | AMSOIL 5W-40 FS 100% Synthetic European Motor Oil | EFMQT-EA |
| Engine Oil | AMSOIL 0W-40 FS 100% Synthetic European Motor Oil | EFOQT-EA |
| Coolant | AMSOIL Passenger Car & Light Truck Antifreeze & Coolant | ANTPC1G-EA |
| Coolant | AMSOIL Propylene Glycol Antifreeze and Engine Coolant | ANT1G-EA |
| Automatic Transmission | AMSOIL Signature Series Multi-Vehicle 100% Synthetic ATF | ATFPK-EA |
| Automatic Transmission | AMSOIL OE Multi-Vehicle 100% Synthetic ATF | OTFQT-EA |
| Brake Fluid | AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid | BFLVCN-EA |
| Power Steering | AMSOIL 100% Synthetic Multi-Vehicle Power Steering Fluid | PSFCN-EA |
Note: Oil filters and air filters have no specific AMSOIL recommendations available in the source data.
Engine Oil Viscosity Specifications
| Temperature Condition | Recommended Viscosity |
|---|---|
| All Temperatures | 0W-30, 0W-40 |
| Above -20°C | 10W-40 |
| Above -25°C | 5W-30, 5W-40, 5W-50 |
Engine Oil Capacity and Service Details
- Oil Drain Plug Torque: 20 ft/lbs
How much transmission fluid does it take?
Capacity varies depending on your specific automatic transmission model (722.3 or 722.4). For both models, the initial fill is 6.6 quarts, while the total fill capacity for a 4-speed unit is 7.7 quarts.
Automatic Transmission Specifications
| Transmission Type | Initial Fill | Total Fill |
|---|---|---|
| 4 Speed 722.3 | 6.6 quarts | 7.7 quarts |
| 4 Speed 722.4 | 6.6 quarts | 7.7 quarts |
For these applications, AMSOIL lists Signature Series Multi-Vehicle ATF and OE Multi-Vehicle ATF.
Other Essential Fluid Specifications
Coolant Capacity and Options
The cooling system capacity is 10.6 quarts. AMSOIL offers two primary options: a pre-mixed ethylene glycol 50/50 formulation (ANTPC1G-EA) and a concentrated propylene glycol version (ANT1G-EA) which requires mixing with distilled or high-quality water.
Brake and Power Steering Fluids
- Brake Fluid: The AMSOIL lookup note references the use of DOT 4 plus (specifically part numbers 0009895605090109, 0009895605110111, or 000989080701) or products approved on MB Sheet 331.0. AMSOIL recommends DOT 3 and DOT 4 100% Synthetic Brake Fluid.
- Power Steering: Recommended for PS015 applications. AMSOIL lists 100% Synthetic Multi-Vehicle Power Steering Fluid.
- Transfer Case: The rear capacity is 2.3 pints (No specific product recommendation available in source data).
Common diesel oil-related concerns and how AMSOIL products may help
| Concern | Why it matters | AMSOIL product from this lookup | How it may help | Important limitation |
|---|---|---|---|---|
| Diesel Injector Deposits | Dirty injectors can reduce performance and increase smoke. | Diesel Injector Clean Fuel Additive | Cleans injectors and lubricates pumps to reduce wear. | Treat rate varies by bottle size. |
| Engine Wear/Friction | High-mileage diesel engines require robust lubrication. | 5W-40 FS Synthetic Oil | Provides exceptional engine protection. | Does not repair existing damage. |
| Cold Weather Starts | Thick oil can hinder startup in low temperatures. | 0W-40 FS Synthetic Oil | Maintains fluidity for better cold starts. | Check local temperature requirements. |
Diesel maintenance notes for this vehicle
Owners of the 1985 Mercedes Benz 300td should focus on maintaining the integrity of the fuel system and cooling components to preserve its legendary longevity. Because these vehicles were designed for high-mileage service, preventative maintenance is key to reaching milestone distances. For turbodiesel models like this ‘td’ variant, monitoring turbocharger health and fuel quality management is a common research priority among owners.
Common maintenance concerns for this vehicle
Based on historical context, owners of the W123 series diesel engines often prioritize the following:
- Fuel System Integrity: Maintaining clean fuel and healthy injectors is vital for the OM617 engine family.
- Cooling System Health: Ensuring gaskets and hoses are intact to prevent overheating.
- Turbocharger Maintenance: As a turbodiesel, regular oil changes are critical to protecting the turbocharger bearings from soot and contaminants.
Recall, TSB, and manufacturer communication notes
Official NHTSA recall research for the 1985 Mercedes Benz 300td returned no recall records. Additionally, no NHTSA complaint records were found for this specific year/make/model combination. However, owners should always verify open recalls by VIN, as applicability can depend on production date, trim, and equipment.
About this vehicle
The 1985 Mercedes-Benz 300td is a diesel-powered variant of the W123 series, a range of executive cars produced by Mercedes-Benz between 1975 and 1986. This specific model belongs to a lineage known for exceptional durability and reliability; historically, many W123 models served as taxicabs in Germany, frequently reaching 500,000 kilometers or more with only minor mechanical attention.
At the heart of this vehicle is a 3.0L 5-cylinder diesel engine, likely belonging to the OM617 engine family. The OM617 is widely regarded as one of the most reliable engines ever produced, with some units capable of exceeding 1,000,000 kilometers without requiring a rebuild. This engine family was a significant factor in Mercedes-Benz’s popularity in North America during the 1980s due to its power and reliability relative to contemporary diesel competitors.
While this vehicle is part of the Mercedes diesel heritage, it is distinct from modern ‘BlueTEC’ systems which utilize different emissions technologies. Owners often explore the use of alternative fuels like biodiesel or vegetable oils with this engine, though proper processing is critical to avoid long-term damage. Note that specific technical specifications such as exact horsepower or torque should be verified through a dedicated service manual for the 1985 model year.
Common questions about this vehicle’s diesel oil and maintenance
What is the oil capacity for my 1985 300td?
The capacity is 8.3 quarts when including a filter change. If your model has an oil cooler that was drained, you may need additional oil.
What viscosity should I use in winter?
For temperatures above -25°C, AMSOIL suggests 5W-30, 5W-40, or 5W-50. For all other temperatures, 0W-30 and 0W-40 are also options.
How often should I change the coolant?
AMSOIL products like ANTPC1G-EA are engineered to provide protection for up to 150,000 miles or 5 years.
Can I use any ATF in my Mercedes transmission?
The AMSOIL lookup lists Signature Series Multi-Vehicle ATF for the 722.3 and 722.4 transmissions.
Does this engine require special diesel additives?
While not required, AMSOIL offers products like Diesel Injector Clean to help maintain injector health and reduce smoke.
How do I check for recalls on my Mercedes?
You should always verify open recalls by your specific VIN through official Mercedes-Benz channels or the NHTSA website.
Disclaimer: This information is derived from provided source data. Always consult your original factory service manual or an official Mercedes-Benz parts catalog to ensure correct specifications before performing maintenance.