I have a 1.6 litre FCA Diesel engine with a variable displacement oil pump, the car is equipped with a DPF and urea NOX system. Factory calls for 0W20 (Acea C2! Try to find an 0W20 C2 oil other than the manufacturers oil!) oil, the same engine the year before (apparently also with a variable displacement oil pump) called for 0W30 (Acea C3) oil. The years before 5W30 (Acea C3) and the base engine block used since mid 00's used to use 5W40 (A3 w/o DPF).
I do encounter oil dilution (as I had with all my DPF cars before, regardless of the manufacturer) - I'm a tad bit worried that the 0W20 becomes a 0W16 or below. Maybe thats why the car only has a 1 year official service interval where it used to be 2 years with x30 oils.
Right now I'm running 5W30 (Acea C3) - with no apparent noticeable ill effects. Since I'm only using that particular car from spring through summer til early fall - I already had in mind going to a C3 5W40 or even a HDEO 10W30.
But I'm concerned with the variable displacement oil pump, which might keep the oil pressure at a low level during cruise. We all know that oil pressure euqals resistance to flow, so having a thicker oil with a variable oil pump with low pressure might end up with too little oil flow?
What I've gathered so far:
a.) I have no idea how the variable pump is designed, or how the software is designed to operate. All I know is that I have a variable pump and that the car is from an era where every last microgram of CO2 reduction is tried to achieve.
b.) While the car is intended to run on 0W20 (Acea C2) oil - even that gets thick in very low temperatures. So in theory a 10W30 in hot summer might be at the same cold start viscosity as a 0W20 in very very cold weather. Since the lather has to work someone might assume the first has to work too. What I dont now here is wether the ECU and its oil pressure regulation system does take outside temperature into account.
c.) How much thicker can I go in terms of operating viscosity without throwing everything out of balance? A respected member on here once wrote that a normal working engine without problems cant be destroyed by any regular viscosity oil. But is that also true with variable displacement pumps that keep pressure to a minimum?
d.) The car might throw codes when too thick of an engine oil is used, but so far I haven't seen any indications with 5W30 C3 instead of the 0W20 C2 oil yet under any circumstances.
e.) The car does see high oil temperatures, at 248°F I slowed down drastically since I got worried with the 0W20 factory fill thinning out too much. One might say the engine has been designed around 0W20, but I personally am not so sure. Basically this engine before used to run on 5W40 - 5W30 - 0W30 before, (older engines pre '10 - 10-14, 14 - 18). 2019 up, where only urea NOX was added suddenly changed to 0W20. My personal opinion is that 0W20 with Acea C2 is used to try to get the consumption as low as possible, but the manufacturer is maybe worried, so its a ACEA C2 0W20 (which is also only availabe from the manufacturer).
What if I have to tow in hot summer with the 0W20 and already high temperatures (which I guess is intended, as a lot of newer cars tend to run a hotter temperature level)? That 0W20 might thin out to a 0W10 due to excess heat?
f.) 6000 miles on 5W30 and the car runs great, oil analysis shows reduced wear. But I know from previous generations (that had no variable oil pump, and earlier versions of the variable pump that might had different software targets) that the engine itself loves 5W40, 10W40 oils. Much better wear metal results. So I would like to make my way back to a 40 weight oil - but I'm unsure wether I might do long term damage due to too much reduced oil flow (a 40 vs a 20 at operating temp at the same pressure the 40 flows much less than the 20) - without noticing it before its too late.
So right now I'm on the fence ... 5W30 Acea C3, 5W40 Acea C3, 10W30 CJ4, 15W40 CJ4 DPF compatoble oils are all available in my personal storage shed.
Whats your take on this?
I do encounter oil dilution (as I had with all my DPF cars before, regardless of the manufacturer) - I'm a tad bit worried that the 0W20 becomes a 0W16 or below. Maybe thats why the car only has a 1 year official service interval where it used to be 2 years with x30 oils.
Right now I'm running 5W30 (Acea C3) - with no apparent noticeable ill effects. Since I'm only using that particular car from spring through summer til early fall - I already had in mind going to a C3 5W40 or even a HDEO 10W30.
But I'm concerned with the variable displacement oil pump, which might keep the oil pressure at a low level during cruise. We all know that oil pressure euqals resistance to flow, so having a thicker oil with a variable oil pump with low pressure might end up with too little oil flow?
What I've gathered so far:
a.) I have no idea how the variable pump is designed, or how the software is designed to operate. All I know is that I have a variable pump and that the car is from an era where every last microgram of CO2 reduction is tried to achieve.
b.) While the car is intended to run on 0W20 (Acea C2) oil - even that gets thick in very low temperatures. So in theory a 10W30 in hot summer might be at the same cold start viscosity as a 0W20 in very very cold weather. Since the lather has to work someone might assume the first has to work too. What I dont now here is wether the ECU and its oil pressure regulation system does take outside temperature into account.
c.) How much thicker can I go in terms of operating viscosity without throwing everything out of balance? A respected member on here once wrote that a normal working engine without problems cant be destroyed by any regular viscosity oil. But is that also true with variable displacement pumps that keep pressure to a minimum?
d.) The car might throw codes when too thick of an engine oil is used, but so far I haven't seen any indications with 5W30 C3 instead of the 0W20 C2 oil yet under any circumstances.
e.) The car does see high oil temperatures, at 248°F I slowed down drastically since I got worried with the 0W20 factory fill thinning out too much. One might say the engine has been designed around 0W20, but I personally am not so sure. Basically this engine before used to run on 5W40 - 5W30 - 0W30 before, (older engines pre '10 - 10-14, 14 - 18). 2019 up, where only urea NOX was added suddenly changed to 0W20. My personal opinion is that 0W20 with Acea C2 is used to try to get the consumption as low as possible, but the manufacturer is maybe worried, so its a ACEA C2 0W20 (which is also only availabe from the manufacturer).
What if I have to tow in hot summer with the 0W20 and already high temperatures (which I guess is intended, as a lot of newer cars tend to run a hotter temperature level)? That 0W20 might thin out to a 0W10 due to excess heat?
f.) 6000 miles on 5W30 and the car runs great, oil analysis shows reduced wear. But I know from previous generations (that had no variable oil pump, and earlier versions of the variable pump that might had different software targets) that the engine itself loves 5W40, 10W40 oils. Much better wear metal results. So I would like to make my way back to a 40 weight oil - but I'm unsure wether I might do long term damage due to too much reduced oil flow (a 40 vs a 20 at operating temp at the same pressure the 40 flows much less than the 20) - without noticing it before its too late.
So right now I'm on the fence ... 5W30 Acea C3, 5W40 Acea C3, 10W30 CJ4, 15W40 CJ4 DPF compatoble oils are all available in my personal storage shed.
Whats your take on this?