Originally Posted By: Gary Allan
The 2007 prohibition on MMO is due to the particulate filters on those and newer models. It's that simple. It's also why you have to use special low SAPS oils.
Fuel is dry. With UCL adds a little is fine. More is not always so. YMMV.
Not quite - MMO is not allowed on 2007 and newer diesels because of the ULSD requirements.
MMO has about 500ppm of Sulfur in it (derived from MMO forum data on how much ULSD is raised when in use) - and using at the prescribed treat rate, will raise the ULSD slightly over the Sulfur requirement for ULSD - therefore they are not allowed to recommend it.
Also - while normal treat rate for MMO (gas and diesel) is 4 oz/10 gallons, Rich Kelly normally recommends 6 oz/10 gallons for diesel to get additional lubricity benefits beyond what diesel already has (it is already somewhat lubricious to start with). 4 oz/10 gallons is enough for gas as it has very little lubricity to start with and gas engines are designed to handle "drier" gas (fuel pumps and fuel injectors).
MMO is also a very good diesel additive, but due to the constraints above, cannot be recommended for diesels that require ULSD.
The 2007 prohibition on MMO is due to the particulate filters on those and newer models. It's that simple. It's also why you have to use special low SAPS oils.
Fuel is dry. With UCL adds a little is fine. More is not always so. YMMV.
Not quite - MMO is not allowed on 2007 and newer diesels because of the ULSD requirements.
MMO has about 500ppm of Sulfur in it (derived from MMO forum data on how much ULSD is raised when in use) - and using at the prescribed treat rate, will raise the ULSD slightly over the Sulfur requirement for ULSD - therefore they are not allowed to recommend it.
Also - while normal treat rate for MMO (gas and diesel) is 4 oz/10 gallons, Rich Kelly normally recommends 6 oz/10 gallons for diesel to get additional lubricity benefits beyond what diesel already has (it is already somewhat lubricious to start with). 4 oz/10 gallons is enough for gas as it has very little lubricity to start with and gas engines are designed to handle "drier" gas (fuel pumps and fuel injectors).
MMO is also a very good diesel additive, but due to the constraints above, cannot be recommended for diesels that require ULSD.
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