Oil-burning Volvo T6 SI6

[YZJB]

Hello all, happy new year! (It’s already 2023 here in Australia)

My mum’s daily is a 2011 Volvo S80 T6 which has the 3.0L turbo six. It has 185,000km on the clock (~115,000mi) and we only bought it recently with just under 180,000km on the odo. I’m aware the 2011s are known for oil consumption.

In that time I’ve replaced the oil and oil filter twice. The first time with Castrol Magnatec Stop-Start A5 5W-30 and a MANN filter. This oil made the car run nicely but it consumed around 1L per 1,000km/620mi. I never let it run low so not a huge problem, but not an ideal rate of oil consumption.

So for the next oil change I thought I’d try an ACEA C3 oil, so I used Nulon APEX+ Multi 2/3 5W-30 which is a C2/C3 oil and was on sale fairly cheaply, so I didn’t care if it burned through it quickly. This really slowed the oil consumption, down to about 0.5L per 1,000km/620mi and in terms of engine noise and smoothness etc. it was either the same or slightly better than the A5 oil.

So, what should I try next to improve things further? I usually have Castrol Edge Professional A3 0W-40 on hand as I use that in our Mk2 and Mk3 Focus RSs. Would this be worth a shot in the Volvo? Or should I just stick to a (relatively) cheap C3 5W-30 and live with some oil consumption?

Thanks for your help and all the best for 2023

Cheers

 

[Greasymechtech]

Definitely work the HTHS ladder. Give the 0w-40 a run, and then the 5w-40 a run.

Probably verify the PCV breather system and make sure all is functioning and nothing clogged up.

 

[YZJB]

Definitely work the HTHS ladder. Give the 0w-40 a run, and then the 5w-40 a run.

Probably verify the PCV breather system and make sure all is functioning and nothing clogged up.

The PCV was replaced by the previous owner within the past 12 months, so I’m pretty confident the crank case breather system is up to scratch. Hopefully higher HTHS and slightly higher viscosity etc. helps out

 

[kebabaluba]

Older Volvos love oil with HTHS above 3.5 so Acea A3/C3 are your best options unless you would do some HDEO like i do in mine.

 

[Oillover]

The PCV was replaced by the previous owner within the past 12 months, so I’m pretty confident the crank case breather system is up to scratch. Hopefully higher HTHS and slightly higher viscosity etc. helps out

Regardless, do a few tests at home to verify it's working properly.
There's one specific tube which feeds into the oil pan. If it's clogged, you'll have consumption issues.
It doesn't take much time/effort/tools to verify it's operating correctly.
Youtube has many vids on how to check the system is operating as intended.

 

[addyguy]

It’s an older car in a warm climate - cheap 15W-40. May reduce consumption, and will save you $$.

 

[GlennDa5id]

Did they replace the whole PCV valve cover assembly or just the PCV diaphragm. The turbo cars did not have the pistons rings with oil burning issues I believe.

 

[YZJB]

T

Did they replace the whole PCV valve cover assembly or just the PCV diaphragm. The turbo cars did not have the pistons rings with oil burning issues I believe.

The entire PCV housing was replaced. Interestingly the oil consumption seems to be gradually reducing since I’ve given it a few short OCIs. I wonder if it had sticky rings and I’m cleaning everything out a bit? Dunno