I'm going to use Mobil 1 High Mileage 5w30 for my van on the next oil change but I noticed that it is only GF-3/SL rated? My van calls for gm6094M (SM). It obviously isn't under warranty with 173k miles and the cat in it is shot, and i'm not changing it. It doesn't burn oil so that wouldn't be a problem anyway. Is there any disadvantages of running a sl rated oil? I presume it is SL because of the extra anti-wear stuff in it. I'm sure it isn't a problem, probably even better that its not sm rated but I just wanted to be sure.
EDIT: Found this
"Oils for these cars will be identical in every way to ILSAC GF-3 oils, except in the area of low-temperature pumpability. The new specification sets maximum allowable low temperature pumping viscosity as follows: 30,000 centipoise at minus 40 degrees C for 0W oils; 40,000 cP at minus 35 degrees C for 5W oils; and 50,000 cP at minus 30 degrees C for 10W oils.
By contrast, the GF-3 specification sets a maximum low-temperature viscosity of 60,000 cP for all three of those grades."
I'll read it later, i'm sure it will answer my question, but now, its grass cutting time!
EDIT: Found this
"Oils for these cars will be identical in every way to ILSAC GF-3 oils, except in the area of low-temperature pumpability. The new specification sets maximum allowable low temperature pumping viscosity as follows: 30,000 centipoise at minus 40 degrees C for 0W oils; 40,000 cP at minus 35 degrees C for 5W oils; and 50,000 cP at minus 30 degrees C for 10W oils.
By contrast, the GF-3 specification sets a maximum low-temperature viscosity of 60,000 cP for all three of those grades."
I'll read it later, i'm sure it will answer my question, but now, its grass cutting time!