Originally Posted by pgtr
I believe the Ecotec in the Sol specs 5W30 meeting GM 6094M. No other SAE viscosities or API performance standards are referenced. What is special or unique about 6094M vs an oil meeting: SAE 5W30, API SM or ILSAC GF4?
Here's the explanation from a few years ago:
Engine oils for General Motors’ 2004 model year passenger cars will have to leap an additional hurdle beyond the ILSAC GF-3 specification, it was announced here Monday.
Speaking before ILMA meeting here, GM’s Roy Fewkes said the automaker has decided that since the introduction of GF-4 oils has been delayed, it needs to reactivate the GM 6094M low-temperature pumpability requirement. The old GM 6094M specification was dropped when API initiated the engine oil licensing and certification system and began identifying qualified oils with the starburst symbol in the early 1990s.
Since then, GM car owners manuals have advised drivers to use only oils displaying the starburst symbol on the container. Now, model year 2004 manuals will advise drivers to use oil that displays both the starburst and GM 6094M.
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.
GM’s Jim Linden says that this additional requirement is being put in place to support the continuation of GF-3 oils since the introduction of GF-4 oils has been delayed.