What oil for tuned diesel engine

[Simone]

I apologize for my english;

I have a Fiat Bravo (2008) 1.6l turbodiesel multijet 120 HP (88 kW).
Recently I got rid of the Diesel Particulate Filter, so the ECU has been reprogrammed, also to obtain more power and torque.

On BITOG, in the document: "Putting the Simple Back into Viscosity" I read:
Load
Equipment loads must also be considered when selecting the proper lubricant viscosity. Under a heavy load, the lubricant film is squeezed or compressed. Therefore, a higher viscosity lubricant is needed

I think my engine works "under heavy load" because of high torque at low RPM

The OEM recommends this: Selenia (Petronas) WR PE 5w-30 ACEA C2 which has Kinematic Viscosity @ 100°C = 10.2 cSt

Do I need a "thicker" oil? If the answer is Yes,
is it sufficient a SAE 30 with Kinematic Viscosity next to the top of the spec (12.5 cSt) or it is better a 0W-40?

I found at a very good price this one:
Shell Helix Ultra Extra 5w-30 Kinematic Viscosity @ 100°C = 12.02 cSt
Meguin Compatible 5w-30 Kinematic Viscosity @ 100°C = 12 cSt

More expensive:
Castrol Edge 0w-30 Kinematic Viscosity @ 100°C = 12.3 cSt
Castrol Edge 5w-30 Kinematic Viscosity @ 100°C = 12 cSt

Obviously, a choice based only on kinematic viscosity is incomplete, but I don't know what additives are in a specific oil, what base is used, ecc.

Than you very much fot the answers

Simone

 

[79sunrunner]

Welcome to the forum!!!! I'm a Fiat guy too, and it's good to have more more guys like you on here. Sometimes, when you choose you prefered viscosity, it comes to you has the best additives for your application. As of now , Shell Helix has been a favorite due to its high NOACK rating, and ability to hold up against loads. Also to consider is the weather in your region, Italy as far as I know is a warm place, and maybe a 0w/40 with your tuned engine would be a great choice. I'd try the Shell 5w/30, and if you can, get a UOA, and experiment. I wish I know more so I could give you more answers/thoughts. But these are just my opinions.

 

[LargeCarManX2]

Can you list the different oils you have available to you....Chevron, Shell, Mobil etc and the general temp and climate of your Country please?

 

[Brybo86]

when i google this car it says the car uses 5w40... I would use 0w40.

 

[supercity]

You could move to a 5w30 C3 lube like Helix Ultra Extra. It is basically the same as the C2 product without the fuel economy aspect. Removing the DPF means you could use an A3/B4 5w30 if you like but given the technology in these late model diesels I would stick with C2/C3 without researching it a little further.

 

[ac_tc]

Whats wrong with a cheaper HDEO xw-40? (italy is fairly warm)
You have already thrown all the emissins equipment out
so theres nothing to be afraid of.

 

[UG_Passat]

Try Shell Helix oils.... it is the brand Ferrai uses for all of their engines.

 

[GSCJR]

^^^^^^


Shell Helix Ultra AP-L 5W-30

 

[Simone]

Thank you all!

Originally Posted By: Brybo86
when i google this car it says the car uses 5w40... I would use 0w40.

This is the old recommendation... after the introduction of DPF, Fiat recommends 5w-30

Originally Posted By: LargeCarManX2
Can you list the different oils you have available to you....Chevron, Shell, Mobil etc and the general temp and climate of your Country please?

I usually buy directly from Germany because, due to different tax rate, I save money.
That said, I can buy all brands available in Germany.

Climate: this is an interesting topic.

My car has a water/oil heat exchanger (nowadays many cars have it, at least in Europe), so why should the choice of the lubricant viscosity be based on ambient temp?
Let me explain:
in the past (20/30 years ago) on turbocharged engine I usually saw 2 radiators, one for coolant, another for oil.
Since the air/oil heat exchanger does't have a thermostat, the temp of the oil varied much with the external temp.
In this case, if I had an average temp=40°C, I would chose a thicker oil or vice versa

In my case, the temp of the coolant (engine warmed up) ranges from 80 to 90 °C, so the oil should be at a higher temp (also because it is used to cool the turbocharger). How much higher depends on the load. Unfortunately I can't read oil temp, it isn't available from OBD2 interface.

We can have both 0°C and 40°C, the coolant however has a temp in that range; maybe at 0°C the coolant is next to 80°C and at 40°C it is next to 90°C.
Consequently the oil is often around 100°C.

I hope the concept is clear.

 

[edyvw]

Originally Posted By: Simone
Thank you all!

Originally Posted By: Brybo86
when i google this car it says the car uses 5w40... I would use 0w40.

This is the old recommendation... after the introduction of DPF, Fiat recommends 5w-30

Originally Posted By: LargeCarManX2
Can you list the different oils you have available to you....Chevron, Shell, Mobil etc and the general temp and climate of your Country please?

I usually buy directly from Germany because, due to different tax rate, I save money.
That said, I can buy all brands available in Germany.

Climate: this is an interesting topic.

My car has a water/oil heat exchanger (nowadays many cars have it, at least in Europe), so why should the choice of the lubricant viscosity be based on ambient temp?
Let me explain:
in the past (20/30 years ago) on turbocharged engine I usually saw 2 radiators, one for coolant, another for oil.
Since the air/oil heat exchanger does't have a thermostat, the temp of the oil varied much with the external temp.
In this case, if I had an average temp=40°C, I would chose a thicker oil or vice versa

In my case, the temp of the coolant (engine warmed up) ranges from 80 to 90 °C, so the oil should be at a higher temp (also because it is used to cool the turbocharger). How much higher depends on the load. Unfortunately I can't read oil temp, it isn't available from OBD2 interface.

We can have both 0°C and 40°C, the coolant however has a temp in that range; maybe at 0°C the coolant is next to 80°C and at 40°C it is next to 90°C.
Consequently the oil is often around 100°C.

I hope the concept is clear.

Ambient temp is important for cold cranking. 0W40 or 0W30 is going to lubricate camshaft and other parts of engine much faster then 5W30.

 

[UG_Passat]

ACEA C category is specially designed for light duty engines, in particular diesel with DPF's and other aftertreatment devices.

Since you removed your DPF... ACEA C2 may not be no longer necessary.

You can expand your search to C3, C4, A3/B4 oils since you have concerns being tuned, so the HTHS min requirements would be higher.

Shell Helix Ultra C is 0w40, ACEA A3/B4...
Shell Helix Ultra 5w30 is also ACEA A3/B4

 

[edyvw]

UG_Passat is right. However, I would stuill stick with Low-Saps oil because of EGR.
Shell Helix Ultra that meets VW 504.00/507.00 has HTHS of 3.68 which is more then enough for your tuned engine.