Technical Croma Oil 9.55535-N2 or S2

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Technical Croma Oil 9.55535-N2 or S2

kozzz

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The Oil classification of Fiat is very vague for me:

  • Fiat 9.55535-M2 Qualification for lubricants with extended drain. OEM recommended product also meets ACEA B3-04/B4-04, GM-LL-B-025.
  • Fiat 9.55535-N2 Qualification for lubricants with a very good characteristics for turbocharged engines, Diesel and gasoline, with extended drain. Minimum requirement is ACEA A3/B4-04.
  • Fiat 9.55535-S1 Qualification for Diesel and gasoline engine, with exhaust treatment system, lubricants, granting fuel economy and extended drain. OEM recommended product is also approved to ACEA C2.
  • Fiat 9.55535-S2 Qualification for Diesel and gasoline engine, with exhaust treatment system, lubricants, with extended drain. OEM recommended product also meets: ACEA C3-04, MB 229.51 and API: SM/CF.
Nowhere have I found out whether the next following (newer oil) is better than the previous one and it is recommended instead of the old one.

Is the oil 9.55535-S2 better than the 9.55535-N2 or does it meet all N2 criteria and can it be used freely instead of obsolete N2/M2?

So, should I better use the 9.55535-S1/S2 in Croma (2006, 150hp) instead of 9.55535-N2/M2?
 
@kozzz

Welcome to Fiat Forum.
While it may seem strange, the newer oils ACEA C2/3 are not as good lubricants as the old (A3/B3) ones. It's to do with compatability between emissions control equipment (Catalysts and DPFs) and oil additives. The older additives can damage the Cat or DPF. The newer additives do not lubricate as well as the old ones.
If your Croma has a DPF you must use the later oil type. If not you can use either and the older is prefered.
I assume you have the 1.9 16V Diesel? In he UK all 1.9 16V Cromas were fitted with DPFs.

Robert G8RPI.
 
Thx. Yes Croma, Diesel 150hp with DPF (Euro 4), that's why the confusion. User Manual recommends Fiat 9.55535-N2 or minimum ACEA B4.

The ACEA European Oil Sequences 2016:


A/B: Gasoline and Diesel Engine Oils – “High SAPS”
A3/B3 Stable, stay-in-grade Engine Oil intended for use in Passenger Car & Light Duty Van Gasoline & Diesel Engines with extended drain intervals where specified by the Engine Manufacturer, and for severe operating conditions as defined by the Engine Manufacturer.
A3/B4 Stable, stay-in-grade Engine Oil intended for use at extended Drain Intervals in Passenger Car & Light Duty Van Gasoline & DI Diesel Engines, but also suitable for applications described under A3/B3.
A5/B5
Stable, stay-in-grade Engine Oil intended for use at extended Drain Intervals in Passenger Car & Light Duty Van Gasoline & Diesel Engines designed to be capable of using Low Viscosity Oils with HTHS Viscosity of 2.9 to 3.5mPa⋅s.

C: Catalyst & GPF/DPF compatible Engine Oils for Gasoline & Diesel Engines – “Low SAPS”
Note: These Oils will increase the DPF/GPF and TWC life and maintain the Vehicle’s Fuel Economy.
C1 Stable, stay-in-grade Engine Oil with Lowest SAPS-Level, intended for use as catalyst compatible Oil at extended Drain Intervals in Vehicles with all Types of modern Aftertreatment Systems and High Performance Passenger Car & Light Duty Van Gasoline & DI Diesel Engines that are designed to be capable of using Low Viscosity Oils with a minimum HTHS Viscosity of 2.9 mPa⋅s.

C2 Stable, stay-in-grade Engine Oil with Mid SAPS-Level, intended for use as catalyst compatible Oil at extended
Drain Intervals in Vehicles with all Types of modern Aftertreatment Systems and High Performance PassengerCar & Light Duty Van Gasoline & DI Diesel Engines that are designed to be capable of using Low Viscosity Oils with a minimum HTHS Viscosity of 2.9 mPa⋅s.

C3 Stable, stay-in-grade Engine Oil with Mid SAPS-Level, intended for use as catalyst compatible Oil at extended Drain Intervals in Vehicles with all Types of modern Aftertreatment Systems and High Performance Passenger Car & Light Duty Van Gasoline & DI Diesel Engines that are designed to be capable of using Oils with a minimum HTHS Viscosity of 3.5 mPa⋅s.

C4 Stable, stay-in-grade Engine Oil with Low SAPS-Level, intended for use as catalyst compatible Oil at extended Drain Intervals in Vehicles with all Types of modern Aftertreatment Systems and High Performance Passenger Car & Light Duty Van Gasoline & DI Diesel Engines that are designed to be capable of using Oils with a minimum HTHS Viscosity of 3.5 mPa⋅s.
C5 Stable, stay-in-grade Engine Oil with Mid SAPS-Level, for further improved Fuel Economy, intended for use as catalyst compatible Oil at extended Drain Intervals in Vehicles with all Types of modern Aftertreatment Systems and High Performance Passenger Car & Light Duty Van Gasoline & DI Diesel Engines that are designed to be capable and OEM-approved for use of Low Viscosity Oils with a minimum HTHS Viscosity of 2.6 mPa⋅s.

SAPS: Sulphated Ash, Phosphorus, Sulphur
HTHS: High Temperature High Shear Viscosity
DI: Direct Injection
DPF: Diesel Particle Filter
GPF: Gasoline Particle Filter
TWC: Three-Way Catalyst
 
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thus, considering that the 9.55535-M2/N2 or at least ACEA B4 is recommended in the Owner Manual, it is logical to use the following (new specifications for DPF engines) such as:
ACEA C1 (Lowest SAPS-Level, HTHS Viscosity of 2.9 mPa⋅s)
ACEA C2 / C3 (Mid SAPS-Level, HTHS 2.9 / 3.5 mPa⋅s.)
ACEA C4 / C5 (Low / Mid SAPS-Level, HTHS 3.5 / 2.6 mPa⋅s)


Or not?
 
thus, considering that the 9.55535-M2/N2 or at least ACEA B4 is recommended in the Owner Manual, it is logical to use the following (new specifications for DPF engines) such as:
ACEA C1 (Lowest SAPS-Level, HTHS Viscosity of 2.9 mPa⋅s)
ACEA C2 / C3 (Mid SAPS-Level, HTHS 2.9 / 3.5 mPa⋅s.)
ACEA C4 / C5 (Low / Mid SAPS-Level, HTHS 3.5 / 2.6 mPa⋅s)


Or not?

Hi,
A C2/C3 oil is ideal. Don't use any B grade oil.

Robert G8RPI.
 
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I've used and they also meet/exceed the requirements:

Selenia WR 5W-40 Engine Oil
Castrol Turbo Edge Diesel 5W-40 - Fully Synthetic
Halfords Fully Synthetic Diesel 5W-40

Unlike a TwinAir or MultiAir petrol engine there is nothing specifically technically challenging other than low SAPs and DPF operation. Low SAPS and DPFs are now common place bog standard diesel engine requirements. A specific Fiat approval is not a requirement (especially when out of warranty)

Selenia WR is a 5W-40, ACEA B3/B4, API CF rated oil and the official oil for the Croma 1.9 diesel engines

Catrol Edge Turbo is a 5W-40, ACEA A3/B3/B4, API SL/CF

Halfords 5W-40 Fully Synth Diesel, ACEA A3/B3/B4, API SM/CF

You can refer to the ACEA Sequences Data you listed to see that the oils I mention are all OK.

Going to a C2/C3 is an option but not required. C2/C3 oils are basically post 2005 era and these C2/C3 oils are specifically targeted at the more modern EU fuel consumption/efficiency measurement requirements/standards.

Going C2/C3 is not a technical issue I believe but will potentially be more expensive.

This is a slightly more user friendly explanation of ACEA oil specs:

https://www.opieoils.co.uk/t-acea-car-engine-oils-specification-explained.aspx
 
It is my understanding that the 1.9 16V DPF engine needs a C2/C3 low SAPS oil. These cars meet EURO 4 emissions even though they did not need to by date.The owners manual is not helpful as it does no differentiate between DPF and non DPF engines.

Robert G8RPI.

Yes you are correct Robert. And Fiat did not help with either their owner's handbooks or their workshop manuals which stated Selenia WR. The also produced an owners DPF Supplement publication about DPF operation etc. but even this did not update the Selenia WR oil requirement.

C2 is ideal for Croma's with DPFs and indeed the later 2006/7-2010 Cromas where changed from Selenia WR to Selenia P.E. (Pure Energy) a C2 rated oil. To my knowledge all the early/firsts 2005 Cromas with 16V 150BHP Multijet engines had DPF filters and were factory fitted with the Selenia WR and all dealers used Selenia WR.

Having owned my Croma 2005 with DPF for over 10 years and a lot of towing I never had any DPF issues because of not using a C2 oil. Also I don't think we have ever seen a DPF filter problem with the Croma's posted in this forum (would need to ckeck). EGR has been the big getting clogged up issues.
 
Maybe being an earlier DPF it's design is more tolerant of contamination. Large diameter long channels and or different catalyst mix. Cost driving to smaller DPFs (small diameter short channels) may make them more sensitive to oil type.
My Chroma had 5 main dealer service stamps for oil change but only 3 resets on the engine ECU oil change counter so either they didn't change the oil or didn't know to reset the service and oil degredation counters.This implies there was little chance of them using the correct oil.

Robert G8RPI.
 
Maybe being an earlier DPF it's design is more tolerant of contamination. Large diameter long channels and or different catalyst mix. Cost driving to smaller DPFs (small diameter short channels) may make them more sensitive to oil type.
Robert G8RPI.

This was my thought as well. Certainly my Croma 2005 had a very large DPF and used differential pressure measurement across the DPF to determine clogging / regeneration timings.

Don't know about later Croma's (would need a VIN to identify production date) but many DPF systems on other makes used just the single pressure sensor in conjunction with (I assume) engine ECU mileage/time/loading parameters. Using a single pressure sensor would be a good cost reduction if the engine ECU data can be relied upon.
 
Just did a check on ePER and it was not until October 2007 that Fiat started changing the DPF and Catalyst system, including pressure sensor changes.

So it is possible for Cromas prior to October 2007 production were still being built and shipped with Selenia WR (non C2 oil).

If the original poster can use his VIN to identify if WR or WR PE is OK. Either way WR PE will cover all bases.
 
Croma, VIN: ZFA19400002030208
I would like to use Total Quartz Ineo MC3 5V-40 (low SAPS, ACEA C3, API SN/C, Fiat 9.55535-S2, FIAT 9.55535-GH2) ?
 
Croma, VIN: ZFA19400002030208
I would like to use Total Quartz Ineo MC3 5V-40 (low SAPS, ACEA C3, API SN/C, Fiat 9.55535-S2, FIAT 9.55535-GH2) ?

Absolutely no problem using the oil you have mentioned / want to use.

For your info your VIN is for:

194.767.0.0 - 1.9 JTD 16V CM 6M 150CV 110KW EMOTION
Engine: 4841324 Vehicle: 02029123 Manuf. date: 31/1/2006

SPECIAL VERSION NO SPECIAL VERSION (LV0)
M 1900 JTD 16V 150HP/110KW (M92)
V EMOTION (V4)
P 5 DOORS (P5)

So date wise Jan 2006 is prior to the October 2007 DPF and CAT changes.
 
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