The great oil debate
BITOG is a great resource.
Oil quality is not even the big issue, suitability for the application is the ticket, have seen one popular LT1 oil put up nothing but mediocre results for the LT1 but put it in a 1.8t VW and the results are awesome. Doesn't make it a great or bad oil, just makes it a great choice for the VW and a not so great choice for the LT1.
Wear metal content in used oil in the intended application is pretty much the only useful test. The rest is smoke and mirrors.
10w30 is only thicker than 5w30 when cold.
Even reading amsoils site they will tell you that you can't just take their oil to 25K in any car or in any condition.


