I'm really sorry to still be asking this,i hope I don't come across as a dim-wit& I am doing me best,but I still can't decipher from all the posts I've read which oil I should buy,there does seem to be several opinions/choices.

So,Which is the correct oil (Brand & Type)for my 2012 T/A.

AL D,thanks for the info on the place near Blackpool,i'm going to speak to them Today,then make a decision whether to take the Car up there,or work with my local guy.
Once again thanks for all the help.
Thanks,Graham.

There's confusion because Fiat changed the spec for the TA engine oil.

Originally, the handbook stated
SAE 5W-40 ACEA C3 grade totally synthetic lubricant.
FIAT Classification 9.55535-S2.

From the factory it would have had
SELENIA K P.E.


Later (I think march 2014 onwards) it was changed to
SAE 0W-30 ACEA C2 grade totally synthetic lubricant.
FIAT Classification 9.55535-GS1.

From the factory it would have had
SELENIA DIGITEK P.E.

Now, it depends on what you think yourself which oil to use.

The Selenia oil is what Fiat contractually use at the factory.
You won't find many dealers using it, no matter what anyone tells you, they'll more than likely (hopefully) use one that meets the correct specification.

Which is either:
SAE 5W-40 ACEA C3 grade totally synthetic lubricant.
FIAT Classification 9.55535-S2
Or
SAE 0W-30 ACEA C2 grade totally synthetic lubricant.
FIAT Classification 9.55535-GS1

There are other brands of oil that meet either of these specs, I think Shell makes one as I seem to remember checking it after my dealer billed me for some after a service.

https://www.shell.com/motorist/oils...semi-synthetic/shell-helix-hx7-ect-5w-40.html
and
https://www.shell.com/motorist/oils...thetic/shell-helix-ultra-ect-c2-c3-0w-30.html

You can find and download the handbook yourself here.
https://aftersales.fiat.com/elum/Home.aspx?id_language=2
If you select brand and model, it allows you to select year and month as well.

BTW, my 4x4 TA was March 2014 and only ever got
SAE 5W-40 ACEA C3 grade totally synthetic lubricant.
FIAT Classification 9.55535-S2

As I wrote, I always checked it after.

There was never any explanation regards the altered spec from Fiat.
I'm a lot of a cynic and think it was due to money for servicing dealers.

They halved the serving intervals and spec'd expensive oil all at the same time, kind of odd eh?

Hi Graham, you could always ring Warrington Motorpark Parts and get price for two 2 litre cans of Selenia 0w 30. Though that Alfa place at Lytham must be able to get hold of it. I had 0w 30 C3 in my previous 4x4. Did 10k miles in 4 months and it was fine. Make of that what you want. You can buy a lot of the correct oil for the price of a Uniair unit.

Shop 4 parts also sell the correct oil in Selina or Petronas (same oil different bottle)

This filtered by Fiat spec brings up these 2. https://m.buycarparts.co.uk/motor-oil-search?release[0]=fiat-9-55535-gs1&viscosity[0]=sae-0w-30

chris3234 said:

Shop 4 parts also sell the correct oil in Selina or Petronas (same oil different bottle)

Click to expand...

While Selenia = Petronas, Digitek P.E. != Synthium 7000

So, same company, different oil, even if the base spec is the same.

Total Quartz Ineo First 0w 30 C2 is Fiat compatible (PSA group) as is Millers XF Longlife C2 0w30. Plenty of choice if want to buy on the high street after all.

Goudrons said:

BTW, my 4x4 TA was March 2014 and only ever got
SAE 5W-40 ACEA C3 grade totally synthetic lubricant.
FIAT Classification 9.55535-S2

As I wrote, I always checked it after.

There was never any explanation regards the altered spec from Fiat.
I'm a lot of a cynic and think it was due to money for servicing dealers.

They halved the serving intervals and spec'd expensive oil all at the same time, kind of odd eh?

Click to expand...

Well, as an engineer, I can say the following:

a) the 5W-40 Selenia seems to be the correct oil for Euro5 TA engines. The MultiAir module will be calibrated to that oil.

b) I like to be a cynic in many cases, but in this case:

c) .... there is a good engineering reasons for the changes:

- Euro6 requires a few changes to the engine, a very common one is the change to a lower viscosity oil. Manufacturers would rather avoid that, as tighter tolerances are required, which makes everything more expensive.

- The long service intervals were most likely causing a lot of warranty issues. The manual always stated that for cars that are used mostly in city traffic and/or do low mileages (<6000 miles per year), an annual service is required. Reasons including, but not limited to, condensate in the oil, which leads to early oil degradation. So while a motorway car with full synth oil should be fine with 18000 miles intervals, the typical use of a twinair engine would lead to a lot of people not changing oil for a few years and thus causing problems. As an engineer I'd change the interval to 9000 miles for a car like the 500 or Panda for that reason alone.

So, sorry for busting the conspiracy theory. But then, I would say that, as an engineer I'm part of "THEM"

Dr.-Ing. habil. Torsten S, CEng, FIMechE

sorry, lots of letters before and after name = credibility ;-)

murphyv310 said:

Hi.
I've scanned my handbook and the Euro 6 supplement.
if we look at Torstens posts re resetting the Uniair module there is some doubt regarding the oil viscosity and whether the old spec should be adhered to on the older engines.

....


Here is the two scans for perusal.

Click to expand...

Interesting scans. That's a pretty good way to confuse the customer and the workshop crew

Since a change from 5W40 to 0W30 (or in general a lower viscosity full-synth) is a common theme in Euro6 engine adjustments, I would not assume that the 5W40 is bad for the engine and was changed because of problems, but because of tighter requirements. I'd stick to the 5W40 for the Euro5 engines - especially since Fiat seems to make it quite clear in your case that the new spec applies only to the Euro6 engine.

Torsten S said:

Interesting scans. That's a pretty good way to confuse the customer and the workshop crew

Since a change from 5W40 to 0W30 (or in general a lower viscosity full-synth) is a common theme in Euro6 engine adjustments, I would not assume that the 5W40 is bad for the engine and was changed because of problems, but because of tighter requirements. I'd stick to the 5W40 for the Euro5 engines - especially since Fiat seems to make it quite clear in your case that the new spec applies only to the Euro6 engine.

Click to expand...

These tighter Euro 6 petrol engine requirements were what exactly?

You only need to be able to read letters to know there are no differences between Euro 5 and Euro 6 emission regulations for petrol engined cars, only diesels had alterations between the two regs.

Both Euro 5 and Euro 6 petrols need to meet the same levels, which are:

CO - 1 g/km,
HC - 0.1 g/km,
NOx - 0.06 g/km
PM - 0.005 g/km

Changing the oil would not have altered anything emissions wise as there was no tighter requirements to meet for this or any other petrol engine.

If it was true, why was there no difference in emission output of this engine after they became Euro 6? Same before, same after.

In fact, Euro 6 TA's still stated 5W40 in their handbooks up until April 2014, quite some time after they started selling them as Euro 6, so it's a fact they didn't need the change in oil to meet the regs.

As is well known on this forum, both earlier and later Multiair units both fail, so to actually pin it on one of the two stated specs of oil in the different versions of the handbook is quite a stretch of the imagination, though the real reasons are another discussion, the truth is out there, it probably is oil related, but level rather than which of the two spec's.

There must have been valid reasons to swap both service interval and oil spec, but they aren't due to tighter emission regulations because there just wasn't any, proof is in the tailpipe!

Don't forget the C3 oil is low ash, the C2 being more conventional. Low ash oils have a reputation of being less protective so that could be the reason for cutting the service intervals.
PS, I too have letters before and after my name.
I'm sure others with degrees and certificates will be as well. Mine though are for electronics.

Why though are C3 oils now specified in a petrol engine? Ash can build up in a diesels DPF but if oil consumption is minimal surely engine oil wouldn't be a big issue.
Oil consumption in a FIRE engine is negligible but C3 oil is specified, perhaps then fiat thought that cat degradation could occur in the TA due to moderate oil useage in the first few thousand miles, just thinking out loud though.

The only change between Euro5 and Euro6 for petrol cars was the introduction of a particle number limit, in addition to the already existing particle mass limit. This was brought in, since the low particle emissions of modern diesel were now below those of (mainly direct injection, but many turbos had problems as well) petrol engines. Apparently it was even necessary to increase the limit by one order of magnitude over that of Euro5 Diesels for the first 3 years, as many petrol engines were not able to achieve the lower limit.

The handbook issue seems to be the one that Trevor pointed out, that the handbook had the Euro5 spec in it, with a supplement for Euro6? So it still seems that all Euro6 had the 0W30 from the start, but in 2014 there would be both Euro5 and Euro6 on the market and the handbook reflected both? Not the best thing in my book to do, because it's just bound to cause a lot of confusion.

Re letters after the name. I was pointing that out tongue in cheek, as I realised that I had gone into lecturing mode (occupational hazard). Disclaimer: I am a thermo- and fluid dynamicist, my last work on engine development was in the 90s, and even back then I was only running design tests on variable valve trains. So the intricacies of Euro5 and Euro6 are not my speciality, I rely on colleagues' expertise for that. What I do know is that in many cases a lower viscosity oil was required, in many others it wasn't really required, but done nonetheless, as there were some efficiency gains to be had. It seems to cause some problems with bearings apparently, as the load bearing capacity of the oil film needs higher pressures - and with oil consumption.

Oh, it seems I'm rambling again. Occupational hazard, see above ;-)

murphyv310 said:

Don't forget the C3 oil is low ash, the C2 being more conventional. Low ash oils have a reputation of being less protective so that could be the reason for cutting the service intervals.
PS, I too have letters before and after my name.
I'm sure others with degrees and certificates will be as well. Mine though are for electronics.

Why though are C3 oils now specified in a petrol engine? Ash can build up in a diesels DPF but if oil consumption is minimal surely engine oil wouldn't be a big issue.
Oil consumption in a FIRE engine is negligible but C3 oil is specified, perhaps then fiat thought that cat degradation could occur in the TA due to moderate oil useage in the first few thousand miles, just thinking out loud though.

Click to expand...

Interesting point about the low ash oil. Could it be that with the introduction of particle number limits, even moderate oil burn could lead to a higher rate of emmision rate fails on that front? My handbook states 400ml per 1000km is considered normal, and I have just topped up 200ml after 620 miles, so am at about half that. Hope it will settle for less than that after the run in period.

Electronics, that's black magic

Goudrons: Agreed, there may be other reasons for the change in oil with the change to Euro6. But I'm certain they are valid engineering reasons, not a money making scheme. I just know from colleagues that there was a lot of development going on at that time not only for diesel, but also for petrol, most engines were definitely not the same before and after.

I guess that the PN limit was brought in because it is less particle mass than size that is dangerous, as it is a quite narrow band of particles that will enter the lung. Too big, and they don't reach the alveoli, too small and they will just be exhaled again. It's the ones that are just the right (or rather wrong) size that enter the alveoli and stay there. Just heard an interesting talk by HSE last week about that subject. IIRC the critical size is somewhere between 1 and 10 microns.

With that in mind, some Euro5 petrol cars where most likely worse than Euro5 diesels, as they'd have had fewer, but smaller particles and could therefore cause more lung damage.