Synthetic Oil-- why can't you switch back/worth it?

viper69 · Post by **viper69** » 18 Nov 2016, 16:18

rspi wrote:This is the most reasonable engine oil thread I have ever read. Lol

I purchased my DD with 189,000 miles, switched to synthetic after I serviced the PCV at 191,000 and now have 333,548. Have done 2 Blackstone oil samples, about to do a third.

My engine has never been opened and developed a leak which I have not fixed at about 300,000.

Thanks for this video. Previous to posting I thought the people who told me one cannot switch back to normal oil were spewing some "crap" because they wanted to make money. But Mobil has no incentive there as they sell both hah. So I'll go w/that.

They claim it doesn't affect seals. IF true, then why do people report leaks at times once they switched? I'm not convinced on this one.

Post by **tryingbe** » 18 Nov 2016, 19:42

viper69 wrote:
They claim it doesn't affect seals. IF true, then why do people report leaks at times once they switched? I'm not convinced on this one.

How would an oil affect seals? If the seal is in bad condition, it's gonna leak. Synthetic flows better than convention, so synthetic oil will appear to be leaking out faster and making a larger pool on the ground.

Post by **rspi** » 18 Nov 2016, 21:06

My take on oil leaks is... synthetic oils have better cleaning agents, etc., so, it will start to clean away sludge, etc. If you have bad or weak seals, and there is some sludge built up around them, and the synthetic oil starts to clean that away, it will probably leak soon. My opinion... change the seals if they are bad. Did synthetic oil cause the leak??? A better question is, would you rather have sludge in the engine or a clean engine with leaking "bad" seals? I'd rather clean the inside of the engine, give it better oil, and fix any leaks.

viper69 · Post by **viper69** » 19 Nov 2016, 12:30

Thanks a lot guys that helps me a lot!

Post by **abscate** » 25 Feb 2019, 05:26

MVS....the only car forum where you can have an oil change interval thread without a flame war, or someone getting banned...

Post by **regent** » 28 Mar 2019, 09:32

I realize I am running the risk of getting banned for exposing the deep secret that the engine oil DOES NOT appear on VOLVO's Lifetime Fluid List

Post by **abscate** » 29 Mar 2019, 04:36

I did Blackstone on both my P2 and P80 Volvos this year. Mobil 1 with 7500 mile changes

Both showed that I could go to 10-12000 miles on those cars with oil still In specs. I’m sticking with a once a year on the P2, and using that oil for make up with the T5, about 1 liter per 2000 miles.

The T5 interval is 3-4 months on its usage schedule.

WhatAmIDoing · Post by **WhatAmIDoing** » 29 Mar 2019, 07:49

abscate wrote: 29 Mar 2019, 04:36 I did Blackstone on both my P2 and P80 Volvos this year. Mobil 1 with 7500 mile changes

Both showed that I could go to 10-12000 miles on those cars with oil still In specs. I’m sticking with a once a year on the P2, and using that oil for make up with the T5, about 1 liter per 2000 miles.

The T5 interval is 3-4 months on its usage schedule.

I think the max interval I would feel safe with is 7,500mi on full synthetic in a turbo charged vehicle. I'm kind of impressed blackstone said you could go over 10k. Are you running Mobil1 10w-40 HM in the T5?

Post by **abscate** » 29 Mar 2019, 07:56

10W-30 Mobil 1 HM in the T5

We rarely breach 90F here in upstate NY, and when I am in the city, I take the Volvo Train down the Hudson in the P-Amtrak model.

Post by **erikv11** » 29 Mar 2019, 11:07

abscate wrote: 29 Mar 2019, 04:36 ... with the T5, about 1 liter per 2000 miles.

That is pretty high consumption for a white block, I'm curious what's the mileage now on that engine?