Engine Oil Help Needed

[Critical Bill]

Good morning guys. I need a help to choose right oil for my 2006 V70 2.4 n/a with 96k miles on the clock.

Since I purchased the car 6 y/a I was using 0w30 a5/b5 recommended by volvo either castrol or shell and replacing every 5k miles.

There was oil a oil consumption roughly 0.7l in 5k miles for the last 4 years.
Not sure if this has somethings to do with volvo dealer overfilled my engine by 0.5l and I was driving with 6 l instead of 5.5 for few weeks.

Anyway I flushed my engine using Tec4 oil flush.
After that I replaced filter , flushed engine with new 5w30 for 20 min drive and drain again.
New filter and new shell oil 5w30 ab/b5 and I must say that oil looks like new till 1.5k and even now at 2.5 does't looks very dark and I'm pretty sure oil consumption is gone.

Now some people recommend to use 10w40 for few volvo models as the 0wXX or 5wXX does not maintain the minimum of 1bar oil pressure at idle.

I was also thinking to switch to ester oil like fuchs titan for example but they don't make them @ a5/b5 the only spec they have in common with recommended by volvo 0W30 castrol is API SL.


So my questions are

1. it safe to use 10W40 or 5W40 is better

2. Is safe to use Ester oil with unknown a?/b?

3. Is safe to switch to a3/b3 or a3/b4 instead of a5/b5.

Thank you all for help

[Georgeandkira]

1) I believe the 5W-40 would have better cold flow rates year 'round so it would just edge out the 10W-40. The 10W-40 would be just fine except during the coldest weather; coldness you probably don't experience anywhere in the UK.

2) I wasn't aware that ester oils lacked an ACEA rating. Since those ratings pertain to viscosity retention when hot (think turbos) and longevity (think cleaning-diesels-GDI engines) requirements, I'd confidently go with either one.

3) Yes, it's perfectly safe to switch to the A3,B3 oil. Our non-turbo cars are way less demanding.

I use Mobil1 0W-40 EF (European Formula) in my '07 NA as well as Total Quartz 9000 5W-40.

[oragex]

I understand the engine is the non turbo petrol. I have no oil consumption (level stays steady on the dipstick) during a 12 month/ 7000 miles oil change interval on my non turbo with 130k miles

About the oil consumption, you don't mention it, but if it wasn't already replaced, it's time for a new PCV regardless if the glove test fails or not https://www.youtube.com/watch?v=rRecTJnTJKc

This is DIY a video for your non turbo https://www.youtube.com/watch?v=3fEjbMpVSfo

May as well look at this video while there https://www.youtube.com/watch?v=gOx3Q8vqoz4

I use OW-40 because I live in Canada so the 0W grade is for very cold starts. But you'll find a 5W-40 to be just find in the milder UK weather. I wouldn't go as far as using 10W-40 because the 10W grade means the oil is pretty viscous at start up especially in colder winter days, may cause more engine wear.

Mobil 1 or Castrol Edge are just fine fore these older engines

[AndyV7o]

Ive written a thread about oil here https://www.volvoforums.org.uk/showthread.php?t=283503 which may contain info you find useful.
I wouldnt go 10w40, get a good 5w40 to A3/B4. Furthermore your hot oil pressure is more related to the hths value than the static viscodity on the label, so an A3/B4 oil will maintain pressure better than an A5/B5. Regardless of whether its 0w30 0w40 5w30 5w40 A5/B5 has hths of 2.9-3.4, A3/B4 has hths greater than 3.5, so, fir example a 0w30 or 5w40 A3/B4 can have a hths of 3.7, whereas both grades in A5/B5 could have a hths of 2.7, this makes a significant difference in oil pressure and hydrodynamic lubrication.
Im hoping to make the above thread a mine of info for people to peruse rather than 60,000 different oil threads all with sketchy details. I would be eternally grateful, if you wish to ask any technical info, if you hopped over to there, with the ideal that the Q&A is there for all to see.
Ill happily help on here though if youd rather or simply cba!