I read the following on the GF-5 website:
Seal Compatibility
Seal compatibility performance is not new to lubricants.
OEMs have their own seal compatibility specifications for their factory fill and service oils, however there are GF-4 oils in the market today that do not meet the targeted seals compatibility performance. OEMs are looking for a performance upgrade so that all oils meet the targeted elastomer compatibility performance.
In GF-5, the compilation of the OEM specs is now becoming a part of the ILSAC/API GF-5 specification. In addition, they are adding a new seal material commonly used by OEMs
Oil leakage can result from a combination of chemical incompatibility between the oil; aging of the seal material and mechanical wear on the seal material. By increasing the number of seal materials evaluated and a more stringent test, elastomer compatibility can be assured.
In addition preventing oil leaks is good for the environment and it keeps the oil where it is needed most - in the engines lubrication system.
The new performance requirement of Seal Compatibility will have a measurable impact on the formulating challenge of GF-5.
Does this mean that the new conventionals will be as good as their HM counterparts in preventing leaks?
Seal Compatibility
Seal compatibility performance is not new to lubricants.
OEMs have their own seal compatibility specifications for their factory fill and service oils, however there are GF-4 oils in the market today that do not meet the targeted seals compatibility performance. OEMs are looking for a performance upgrade so that all oils meet the targeted elastomer compatibility performance.
In GF-5, the compilation of the OEM specs is now becoming a part of the ILSAC/API GF-5 specification. In addition, they are adding a new seal material commonly used by OEMs
Oil leakage can result from a combination of chemical incompatibility between the oil; aging of the seal material and mechanical wear on the seal material. By increasing the number of seal materials evaluated and a more stringent test, elastomer compatibility can be assured.
In addition preventing oil leaks is good for the environment and it keeps the oil where it is needed most - in the engines lubrication system.
The new performance requirement of Seal Compatibility will have a measurable impact on the formulating challenge of GF-5.
Does this mean that the new conventionals will be as good as their HM counterparts in preventing leaks?