Audi Junkie

Magnesium additives can increase friction and there are some other undesirable side-effects that I can't recall, that's why it's not used anymore. Belgian Syntec was rushed over to make-up the gap in VW 502 oils when Audi had the big sludge problems. Seriously, brands aside, what is preferable for the same money, German Syntec 0w-30 with cutting-edge Methylcrylate base oil and high-tech additives or old Belgian Syntec, formulated for 1998 A3 spec? A3/VW 502 spec is very unimpressive, Blends and Dino can meet it. I'd just assume use Mobil Clean with it's solvent-dewaxed G-III/PAO base and state-of-the-art Antimony/Borate ester additives. OTC oils for V6 is unlimited choices, for 1.8t, I'd stick with GC, Mobil 1, Pennzoil Platinum (unique Gas-to-Liquid POE base, equal to or better than PAO at $4/q)
PS I use the thick GC in my new Acura, where 5w-20 is specified....InsAniTY!!!

diagnosticator1

BTW, the InsAniTY can be an advantage in some ways, you are fortunate the you are aware of it, most of those afflicted, don't know it, and it shows! (J/K!)

Audi Junkie

but their +100c visc is thicker to make the HT/HS, GC does it with thinner +100c visc, say 12cSt for GC vs 14cSt for others. Redline is the exception, their HT/HS is always higher than comparable visc oils. Another thing to consider is an oil like M1 0w-40 starts at 14cSt, but shears below GC's 12cSt to rethicken from oxydization. Ok, so...what happens to the HT/HS mid oci? It probally drops along with visc. GC stays at 12Cst, no shear, good consistant HT/HS and relatively good mpg due to the thinner visc. It's super-smooth too. My engine runs like an electric motor. Here is one guy's personal account vs AMSoil...<ul><li><a href="http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=51;t=001081">http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=51;t=001081</a</li></ul>