VOLVO FH / FM : General information about oils and greases

Lubrication is very important when it comes to service and maintenance of the truck. Vehicle components such as the engine, gearbox, rear axles etc must be lubricated with either oil or grease.

VOLVO FH 520 HP TRUCK FROM COAST LINERS 

Oils 

For components that are lubricated with oil, the grade, viscosity and service interval are very important. The type of oil to be used for a specific component depends on the oil's grade and viscosity. This information can be found on the container and / or on the oil's product information sheet. When a specific part number is recommended, the part will always have the correct grade and viscosity for the purpose. 

Synthetic Oil 

Synthetic Oil is being used increasingly for the lubrication of vehicles. The raw material for these oils is the same as for mineral based oils, raw oil but the manufacturing processes are rather different. As a rule, synthetic oil has better temperature stability and cold properties but its friction properties sometimes result in sycnhronisation faults. Synthetic oil can also have a negative effect on sealing materials. It is therefore important that approved synthetic oil is used. 

A synthetic oil is not necessarily better than a mineral oil. This is however a common misunderstanding and extended oil replacement intervals are therefore assumed. The service interval recommended by VOLVO apply irrespective of whether the oil is mineral based or synthetic. 

Grade 

A large number of grade designations are used. Different oil types have different grade designations. 

Viscosity 

Viscosity is a very important property in an oil. It is a measure of the runability of the oil, which effects the thickness of the oil film and fuel consumption. The ambient temperature in the area where the truck is used, determines which viscosity is recommended. 

There are two systems, called SAE viscosity grade classifications, which divide oils into viscosity grades (such as SAE 10W, SAE 80W-90 etc).

Engine oils and transmission oils belong to two different systems. It is therefore always important to know within which system the viscosity grade is specified. 

For example, engine oil with a viscosity grade SAE 40 has approximately the same viscosity as transmission oil with the viscosity grade SAE 90. However, in both systems, a higher number indicates a higher viscosity. 

Service Interval 

When it has been decided which oil should be used (i.e, the quality and viscosity are known), the recommended service interval is fixed. 

Grease 

For components that are lubricated with grease, the grease type and service intervals are very important. The type of grease to be used for a particular component is given under each component respectively. The information can be found on the grease container and / or on the grease's product information sheet. 

In some cases, using grease with a particular VOLVO part is recommended. If this grease is used, the correct type is automatically obtained. 

Grease Types 

Type of grease is determined by a number of different properties, for example 

• Type of thickner, which can be lithium, lithium complex, polymer or clay
• Grease consistency, specified by the NLGI number
• The prsence of EP additives
• The occurence of solid lubricants, such as graphite, copper or molybdenum sulphide

Excerpts and information Source : VOLVO FH / FM Manual