Do diesel engine oils for modern turbo direct injection diesel cars benefit from being Grp IV or Grp V base stock? They are not high reving; I don't think they run particularly high oil temps; and I don't think they run with a lot of fuel dilution - - or at least the typical fuel dilution level is not that harmful. Am I wrong on any of these counts?
Does diesel PCMO nee to be Grp IV?GrpV?
- Thread starter m6pwr
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A direct injection engine does give more fuel dilution and we are seeing this as a problem on gas engines. A new Sonata I service is really hard on the oil with a conservative driver. I hear that Hyundai is coming out with a higher viscosity 20W for this problem.
Originally Posted By: m6pwr
Do diesel engine oils for modern turbo direct injection diesel cars benefit from being Grp IV or Grp V base stock? They are not high reving; I don't think they run particularly high oil temps; and I don't think they run with a lot of fuel dilution - - or at least the typical fuel dilution level is not that harmful. Am I wrong on any of these counts?
The exact content of most modern Euro oils is difficult to ascertain.
Don't forget these oils are made for high-speed driving.
Do diesel engine oils for modern turbo direct injection diesel cars benefit from being Grp IV or Grp V base stock? They are not high reving; I don't think they run particularly high oil temps; and I don't think they run with a lot of fuel dilution - - or at least the typical fuel dilution level is not that harmful. Am I wrong on any of these counts?
The exact content of most modern Euro oils is difficult to ascertain.
Don't forget these oils are made for high-speed driving.
I know fuel dilution and consequent intake deposits are an issue in gasoline direct injection engines, particularly turbo GDI, but from what I've read, diesels can tolerate much more % fuel dilution - - as much as 8% . If I had a GDI turbo I probably would make a special effort to find at least a PAO oil if not an ester base, but do I need to to find an oil like that for a diesel car? I've got an '11 BMW 335d. The service fill is Castrol SLX Professional OE 5w30, a GRP III low SAPS oil. Seems like an oil adequate to the task, as far as I can tell..
SLX Professional OE "adequate to the task"
Not in my experience with an X5 35d. TBN dropped to 1.5 and
TAN went up to 4.8.
So I'm using Delvac 1 LE, an ACEAE6/e4/E7 /MB228.51 oil.
Charlie
Not in my experience with an X5 35d. TBN dropped to 1.5 and
TAN went up to 4.8.
So I'm using Delvac 1 LE, an ACEAE6/e4/E7 /MB228.51 oil.
Charlie
Originally Posted By: m37charlie
SLX Professional OE "adequate to the task"
Not in my experience with an X5 35d. TBN dropped to 1.5 and
TAN went up to 4.8.
So I'm using Delvac 1 LE, an ACEAE6/e4/E7 /MB228.51 oil.
Charlie
yet it has not been proven that TAN is relevant in diesel engines. Engines have been run with TAN as high as 8 & TBN @1 with no ill effects.
SLX Professional OE "adequate to the task"
Not in my experience with an X5 35d. TBN dropped to 1.5 and
TAN went up to 4.8.
So I'm using Delvac 1 LE, an ACEAE6/e4/E7 /MB228.51 oil.
Charlie
yet it has not been proven that TAN is relevant in diesel engines. Engines have been run with TAN as high as 8 & TBN @1 with no ill effects.
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Hi,
BMWTurboDzl - Actually TAN is most relevant to diesel engines. This is because of the variable quality of distillate's sulphur levels
As an example and over many millions of kms/miles my averages of all engines at OCI (90kkms) was TAN 6.13 and TBN 2.26
Modern diesel engines seem to benefit most from the synthetic's (Grp3>) properties
BMWTurboDzl - Actually TAN is most relevant to diesel engines. This is because of the variable quality of distillate's sulphur levels
As an example and over many millions of kms/miles my averages of all engines at OCI (90kkms) was TAN 6.13 and TBN 2.26
Modern diesel engines seem to benefit most from the synthetic's (Grp3>) properties
Originally Posted By: Doug Hillary
Hi,
BMWTurboDzl - Actually TAN is most relevant to diesel engines. This is because of the variable quality of distillate's sulphur levels
As an example and over many millions of kms/miles my averages of all engines at OCI (90kkms) was TAN 6.13 and TBN 2.26
Modern diesel engines seem to benefit most from the synthetic's (Grp3>) properties
Does the introduction or ULSD largely negate the concern over levels of sulfur and IIRC reading somewhere were you had stated that you work found no discernible differences on engine wear which had oil with extremely high TAN numbers.
From reading your comments I inferred that it was ointless to worry about TAN levels in passenger cars doing 12k mile OCI.
Hi,
BMWTurboDzl - Actually TAN is most relevant to diesel engines. This is because of the variable quality of distillate's sulphur levels
As an example and over many millions of kms/miles my averages of all engines at OCI (90kkms) was TAN 6.13 and TBN 2.26
Modern diesel engines seem to benefit most from the synthetic's (Grp3>) properties
Does the introduction or ULSD largely negate the concern over levels of sulfur and IIRC reading somewhere were you had stated that you work found no discernible differences on engine wear which had oil with extremely high TAN numbers.
From reading your comments I inferred that it was ointless to worry about TAN levels in passenger cars doing 12k mile OCI.
Hi,
BMWTurboDzl - ULSD has changed the rules somewhat. Obtaining a TAN is somemwhat pointless in (diesel) cars doing 12k per annum and where ULSD is used exclusively and an Approved lubricant is in place
The TAN/TBN ratio is useful in high utilisation operations and/or where ULSD is not available - and etc
BMWTurboDzl - ULSD has changed the rules somewhat. Obtaining a TAN is somemwhat pointless in (diesel) cars doing 12k per annum and where ULSD is used exclusively and an Approved lubricant is in place
The TAN/TBN ratio is useful in high utilisation operations and/or where ULSD is not available - and etc
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