after using dino oil for so long? The point with synthetics are to start using them after break-in and prevent any additional wear. Yes, it "could" help the turbo bearings live longer but so will good quality/consistent oil changes using Dino oil. My brothers 94 850 turbo wagon got 190k out of his turbo using that philiosphy. Synthetics are for the people who do NOT maintain there cars!
The oil has a longer service life! Change your Dino oil every 3500 miles max and be happy! Save your money!

There is more difference between synthetic oils than there is between non-synthetics.
Some "synthetics" use hydrocracked base stock, which can approach (but not equal) the capabilites of PAO.

In my biased opinion, the best oil available is AMSOIL Series 2000 0W-30. Second choice is AMSOIL 5W- or 10W-30. If I couldn't, or wouldn't, use AMSOIL, then I'd go with Mobil 1 xW-30.

You can mix brands and viscosities, but no need to go to anything higher than xW-30.

Sorry I missed your questions w/ my previous reply. Any full synthetic under $4/qt. is a good by. I am not a big fan of Pennzoil...their petro base oil is a sludge magnet. You can change weights and even mix syn with petro based if needed. Don't mix different weights, though.

I have a '99 S70 T-5 5-spd. I use Valvoline syn oil in the motor and syn lube in the tranny. I have gone to Valvoline syn lubes in my '91 300ZX and '71 240Z. I use Valvoline Dura-Blend in my Minivan and and children's cars. I have always used Valvoline products and have had no problems. Mobil 1 is good. From my research, Amsoil appears to be the best. You could look at Redline and Royal Purple. You need to buy from a rep and these run about $7.00. Most syn cost about $4.50/qt. For the typical driver doing regular oil changes, they will all perform well. Many manuf are recommending syn oil especially for turbos that run hot. Syn oils don't coke the way petro based does. A blend oil (petroleum and syn, i.e. Dura Blend) traps more contaminants (petro portion) and resists breakdown (syn portion). A syn flows better at cold temps and is usually rated as 1 weight higher than a petro based of the same weight. It breaks down much less at sustained high temp running. It is great in manual trannies for synchros and cold shifts. One word of caution, stay away from additives. Use a good filter always...the Volvo Mann filters are good. Hope this helps.

No.

Go to bobistheoilguy.com

Some "synthetic" oils are not "synthetic" at all. Unfortunately, like a lot of things in life, it's all marketing. Learn about Group III oils......then compare them to true synthetic Group IV and V's.

Mobil 1 is a good motor oil. It has some properties I don't like, but it is a good oil.
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