Quote
... a good synthetic 5W-30 has meager evaporation and stability, better than most cheap 15W-40s...


Considering there is no good synthetic 5w30 oil in USA (exept for Amsoil) 15w40 (which is a diesel oil) actualy does help with oil consumption.

I'm using 1qt every 300-400 miles when using 5w30 Castrol Syntec or Mobil1.
After switching to Shell Rotella 15w40 i'm up to 1qt every 1,000.

Real synthetic oils available in USA include (but not limited to) Castrol Syntec 5w40 (formulated for Volkswagen turbo engines), Mobile1 0w40 (European formula), Amsoil (all of the grades), Dello400 synthetic 5w40 (Diesel) and Shell Rotella Synthetic 5w40 (again Diesel).

Every other "synthetic" oil on the market IS NOT a true synthetic (Mobil1 being Class4, comming realy close to a true synthetic, but still not as good as Class5 oils listed above).

Just my $.02

"If i can't crawl over it, i'll fly over it"
rubo

'96 Amigo 4x4, 3.2L V6, 4L30E, D44 rear, SOA, 1" BL, undergoing surgery.
'00 Rodeo LS 4x4, 3.2L V6, OME 919 Springs, front cranked to match,1" BL, 265/70x16 Scorion A/T's.