Oil recommendations
 

What oil do you recommend for 850 turbo with 120,000

Synthetic would really be your best bet, not sure what viscosity these engines like.

this is not a recommendation but this is what i have been using and its fine for my C70 1998

I use Mobil 1 Fully Synthetic 5W-50

My V70 T-5 is currently running 15W40 Synthetic.

I run Castrol Synthetic 5w30 and add a oil additive called MOA by BG.

On all our Volvos I used Mobil 1 10-30W.........but for our 2001 V70 with 115,000 miles, I've just switch to Mobil 1 10-30W High Mileage version which has some additives for older vehicles that help to reduce engine wear, protect seals, etc. You can get the details from the Mobil 1 Website.

won't the synthetic expose the little leaks

Ive used synthetic in a car with around 70,000 miles with no leaks and used it all the way up to 180,000 miles and the car had no major leaks. The only gaskets I replaced were the valve cover gaskets.

I think as long as your car is not leaking anything really bad, you will have no problems with it.

I used Valvoline 10W30 Synthetic Blend for high mileage cars and change it every 3,000-4,000 miles. The closer to 3,000 the better.

Just a suggestion; Be careful with the high mileage oils in turbo engines. They cling longer and therefore may burn slightly in your hot turbo oil lines and cause a blockage. I burnt up a turbo on my supra this way....

Thanks for the input on this..........the Turbos always had some complications to the equation. Were you using Mobil 1 High Mileage or some other high mileage brand and at what mileage interval did you change the oil? I've also seen high mileage or extended mileage formulas in the conventional oils, too. I noticed one person uses synthetic and also adds BG MOA oil additive but don't know if he has a Turbo car or not.