Q4 Oil - Fully syn or semi-syn?

[AlfaJack]

What do you use?

So, would you recommend a fully synthetic or a semi syn? Is the general rule that fully-syn will always be better for an engine than semi-syn?

Currently I have Fuchs Titan Race Pro S 10W-60 but it is a touch expensive (what is in the car was free for swapping some shocks for a forum member

What about this?:
http://www.camskill.co.uk/m1b0s5592p..._5_Litre_-_5L_
Any recommendations appreciated.
Cheers,
Jack

[Steve Webb]

Hi Jack, I think the fully synth oils hold together better for longer with the high temps inside the engine, (around the turbo etc)

I always used to use Agip (now eni) Racing which was a 10/60 oil, but lots of the Integrale lot used Motul 300v which was supposed to be slightly better. Both of those are fully synthetic.

People used to avoid the old Mobil 1 because it was a 0/40 oil, and it was very thin even when cold. The thinking was that it was actually thin enough to drain fully from the various parts of the engine and not give you any lubrication until it had been pumped back round.

[mpampis_]

I am using valvoline 10/60. Normal cost and nice oil

[jimnielsen]

I couldn't even imagine using non synthetic oil. Castrol Edge 10w60 is $70.00 AUD here .. that's about tuppence ha'penny in British pounds! Mobile 1 is just too thin for the Q4's oil pump - I am sure it works well in more modern cars.. Having paid for more than a few 'oil analysis' readings with the Castrol Synthetic, I can certainly say that it works well. You can't really buy the Aguip product here.. so i have had no experience with it..


jim ~

[Suzumushi]

I am using valvoline 10/60. Normal cost and nice oil

can confirm that
i'm also using valvoline vr1 racing 10w60 for a couple of years
previously (but not in q4) Motul 300V le mans and Castrol RS

regards

[Steve Webb]

Isn't the Valvoline VR1 a semi-synth oil though:

Valvoline VR1 Tech sheet

[mpampis_]

10/60 is full synth. I pay every time 80 euro for 6 litters and oil filter

[Suzumushi]

10/60 is full synth. I pay every time 80 euro for 6 litters and oil filter

Nope,
as Steve wrote, vr1 is not a full synth oil, but it's still my number one choice

regards

[mpampis_]

You are right. I change them every 7000 km

[AlfaJack]

I couldn't even imagine using non synthetic oil. Castrol Edge 10w60 is $70.00 AUD here .. that's about tuppence ha'penny in British pounds! Mobile 1 is just too thin for the Q4's oil pump - I am sure it works well in more modern cars.. Having paid for more than a few 'oil analysis' readings with the Castrol Synthetic, I can certainly say that it works well. You can't really buy the Aguip product here.. so i have had no experience with it..


jim ~

Cheers all, thanks for the advice.
Re oil being too thin, I remember when my dad put Mobile 1 in his 164 3.0 - it seemed to burn through it at an alarming rate!
However - 10/60 should be the same thickness as any other 10/60 across any temp range no matter who makes it?

[Steve Webb]

Nope,
as Steve wrote, vr1 is not a full synth oil, but it's still my number one choice

regards

Which neatly brings us back to Jacks original question of what is the difference between Semi and fully synthetic oil.

[mpampis_]

In my opinion there is no difference if you change them about every 6-7000 km

[Evodelta]

In my opinion there is no difference if you change them about every 6-7000 km

Then use fully synthetic and leave it in for longer.

[mpampis_]

I like refresh the oil and the filter quicker so I am pleased with that

[AlfaJack]

So, is everyone using 10/60 or is anyone on 10/40?
I was made aware today that I am actually using a 10/50 at the moment.
Also I was questioned as to why I wanted a 60 when the car is specified for 40.

All I could suggest was that other owners use a 60 and that it keeps the oil pressure up. He said all I was doing was making the engine work harder and he would recommend keeping to the handbook.

Any thoughts on the right oil weights for this engine?

[Steve Webb]

I was under the impression that the numbers related to the temp that the oil stayed stable at. The first number is the lower temp, the second is the higher temp. So a 10/60 is not necessarily thicker than a 10/40 at normal temps, but will retain its thickness until a higher temp.

Could be talking rubbish though.

[Evodelta]

When deciding what to use the main factors are:

Mileage and wear of engine.
Usage, track day, road etc.
How often you change it.
Your local climate temperature.

Put oil in which suits you and your engine, the manufacturers of the engine aren't usually wrong.

[AlfaJack]

112K miles
All sorts of driving on the roads...rarely track days
Changed about every 5K miles

Looking at that I feel I don't really have to go OTT and spend £50 on the oil.

[Evodelta]

If your oil pressure is showing ok then I would be putting in a 10/40 SS and changing at 6k. Anything more than that is overkill and a waste of money.

I use Millers for a couple of reasons; They have a very good range of high quality products and they are local to me.
I can go over to pick my oils up and get to talk to the people in the tech department, they are of the view that many enthusiasts such as us are a bit too precious and throw out our oil far too early, their FS oils now will do 10,000 road miles quite easily in your average turbo engine.
As you may have read elsewhere I took them a sample of 10/60 FS to analyse, it had been in a new engine which had done 4000m of mixed road miles and remapping time then onto a full trackday where it was driven as hard as possible all day long, oil temps of 100'c and 8500rpm weren't uncommon.
As a rough rule of thumb they reckon a trackday is about the equivalent of a years normal road driving in terms of wear and tear on your car, it's far from scientific though!

The oil was deemed to be perfect and could have stayed in even longer......

The only oil I have seen which (if they still make it) I would avoid is Castrol RS, it had a reputation for a terrible black sludge problem and I have indeed seen the inside of an engine which used it and didn't look too good to me, whether it did any harm or not I don't know.

[AlfaJack]

Cheers Martin. Sounds good to me.

[buncheQ4]

Hi , Do you know Mobil1 5-50 ?. How is it?

[Evodelta]

5 is too thin, you need at least a 10.

[wrinx]

10/60 is apparently the best oil to use for the 16v turbo lump but it's not cheap in the UK.

I've got a bottle to throw in mine...but I need to find out where the oil is disappearing from before I stick this liquid gold in the sump!

rinx