Engine Oils Opel Senator B

This Technical Information Bulletin replaces TI-C-28, Group J-127, dated January 1989

Subject: Engine Oils

Vehicles: All

As in many other areas of our production, engine oils are constantly being further developed. Opel / Vauxhall prescribe "minimum oil qualities" for petrol and diesel engines. A higher oil quality, such as API-SG, is even better at decreasing oil oxidation and formation of sludge and in addition protects against wear. High quality oils are always to be recommended, in keeping with the motto "only the best is good enough".

Passenger car engine oils are selected on the one hand according to viscosity (SAE) and on the other according to quality (API and CCMC). As regards viscosity, nowadays, multi-grade oils, e.g. SAE 15W-40, and easy run oils, 5W-X and 10W-X, are the most extensively used all-year engine oils.

Since 1980/81, single and multi-grade or easy-run oils with the classification API-SF / CC or SF / CD are available on the market. The highest quality products available are API-SG / CD since 1988 and CCMC-G5 / PD2 since 1990. What do these designations mean ?

Viscosity According to SAE Classification

The "flowability" of engine oils is determined according to the viscosity classes set by the SAE, "Society of Automotive Engineers" (USA) (SAE J 300 or DIN 51511, June 1987).

Allocation to viscosity classes depends on viscosity at high and low temperatures. The classes are designated by letters and digits: 0W, 5W, 10W, 15W, 20W, 25W, and 20, 30, 40, 50 and 60. The numbers with "W" (Winter) identify the viscosity at low temperatures, the numbers without "W" at high temperatures. A low number means "more thin-bodied".

Oils which fulfil both requirements - multi-grade oils - receive both designations, e.g. SAE 10W-40.

The viscosity patterns can be graphically represented.

The illustration on the right shows the comparison between a multi-grade oil SAE 10W-40, a single grade oil SAE 30 and an easy-run oil 5W-50.

Line I : SAE 10W-40 multi-grade oil

Line II : SAE 30 single grade oil

Line III : SAE 5W-50 easy-run oil

For example, at low temperatures, the SAE 10W-40 flows better than the SAE 30 and thus makes cold starting easier. The greater the temperature in the operating range, the more marked the advantage of the SAE 10W-40 oil relative to the SAE 30 oil, the viscosity of which noticeably deteriorates with the increase in temperature. The main advantages of multi-grade oil to single grade oil become obvious here. The best cold start performance is achieved with easy-run oils of 5W quality. At high temperature loads, viscosity class 50 or 60 makes an important impact on the endurance of the lubricating film.

Quality According to API Classification

A well-known classification system for passenger car engine oils are the API classifications (American Petroleum Institute). Here, oils must successfully go through test runs in normed test engines, with different API classes for petrol engines (SA to SG) and diesel engines (CA to CD). The further the second letter is down the alphabet, the better the quality. Therefore, SG for petrol engines and CD for diesel engines are the best quality oils at the moment.

The mineral oil industry designates its oil products by viscosity classification and API classification. Oils that fulfil more than one classification and which are suitable for both petrol and diesel engines may be thus designated, e.g API-SG / CC or API-SG / CD. Only a few "imported" engine oils may not have API designations. Such oils are not approved for our engines.

Quality According to CCMC Classification

The CCMC classification was introduced by European car manufacturers to differentiate between engine oil qualities, taking into account the special lubricating requirements of engines in European vehicles. CCMC stands for Comité des Constucteurs d'Automobiles du Marché Commun (Committee of Engine Manufacturers in the EEC). The CMMC specifications are derived from even stricter tests than those used by API. According to these, CCMC G5 for petrol engines and CCMC PD2 for diesel engines are the best quality oils at the moment.

Other Specifications

Besides the API and CMMC classes, US military and General Motors specifications are also used to determine the minimum performance properties of engine oils.

There are correlations between all specifications.

The CCMC classifications are allocated as follows:

G5 = Easy-run oils

G = Gasoline / (for petrol engines)

D = Diesel / (for diesel engines)

PD = Passenger-Car-Diesel / (for passenger car diesel engines)

The quality specifications according to MIL-L-.... (Military-Lubricants) or GM correspond to API classes as shown on the right:

Easy-run Oils

Easy-run oils (fuel-saving oils with low cold viscosity) may be used in Opel / Vauxhall engines.

A precondition is that these properties be explicitly mentioned in the product descrpition on the container, and that the quality correspond to API-SG / CD or CCMC G5 / PD2.

Engine Oil Change Intervals

As of Model Year 1987

Engine oil is changed and full-flow oil filter replaced every 12 months in the Opel / Vauxhall Annual Inspection, or after the following distances have been driven:

Petrol engine = 15,000 km/9,000 miles

Diesel engine = 7,500 km/4,500 miles

In the case of low mileage accumulation with frequent cold starts or predominately city and short distance driving, additional engine oil changes and filter replacement may be advisable.

Engine Oil Viscosity

The following engine oils may be used for petrol and diesel/turbodiesel engines:

A = Single grade oils

B = Multi-grade oils

C =Easy-run oils

depending on the outside temperature.

Important: In all 6-cylinder engines, use only multi-grade oils or easy-run oils.

Engine Oil Quality

The engine oil quality must correspond to the API and CCMC classifications. Oils which fulfil more than one classification are designated appropriately, e.g. API-SG / CD and CCMC G5 / PD2.

For Opel / Vauxhall engines, use the following API / CCMC classifications:

Important: CD engine oils which are explicitly designated as oils for diesel engines by the mineral oil manufacturer are not suitable for petrol engines, unless a performance class which is adequate for petrol engines is also given (e.g. API-SF / CCMC-G4).

Oil Additives

Modern engine oils are already provided by the mineral oil manufacturer with all necessary additives. These additives consist of detergents, dispersion agents, antioxidizing agents, high-pressure additives, flow improvers, etc.

These additives are matched to one another by the mineral oil manufacturer and can in some circumstances be negatively affected by mixing in other additives subsequently.

Disposal

For disposal of waste oil, observe the relevant national regulations.