The different oils in Amsoil's product line with the same viscosities are made with differing basestocks. You probably should take the time (since you are NOW a BiTOG reader
) to find out about basestock chemistry and all about group I through group V (1-5).
For example, Amsoil makes 3 5w30's, the HDD with more ester basestock (one of the true synthetic bases) and HD additives (for diesels), ASL - a PAO (one of the other true syns) based very solid automotive 5w30 at a decent price - the oil that I think would be a great choice in your car, and the XL-7500 5w30, which indeed is overpriced, because it's not a "true" synthetic, it's a "super refined", hydrocracked petroleum base, but it's not a synthesized base....follow me?
As for Amsoil testing, they lately have been mostly testing the ASL and it's 10w30 brother, ATM. These oils are good oils and do well in many standardized tests, as well as in the real world. These really are the only oils I sell, along with 15w40 and 10W-40's that are both PAO based. These oils can be had for about $4.50 a qt.
The XL's which aren't much cheaper, probably would not come close to ASL/ATM in these tests, but they are API "certified", so they fill a niche, I suppose.
[ December 22, 2003, 12:33 AM: Message edited by: Pablo ]

For example, Amsoil makes 3 5w30's, the HDD with more ester basestock (one of the true synthetic bases) and HD additives (for diesels), ASL - a PAO (one of the other true syns) based very solid automotive 5w30 at a decent price - the oil that I think would be a great choice in your car, and the XL-7500 5w30, which indeed is overpriced, because it's not a "true" synthetic, it's a "super refined", hydrocracked petroleum base, but it's not a synthesized base....follow me?
As for Amsoil testing, they lately have been mostly testing the ASL and it's 10w30 brother, ATM. These oils are good oils and do well in many standardized tests, as well as in the real world. These really are the only oils I sell, along with 15w40 and 10W-40's that are both PAO based. These oils can be had for about $4.50 a qt.
The XL's which aren't much cheaper, probably would not come close to ASL/ATM in these tests, but they are API "certified", so they fill a niche, I suppose.
[ December 22, 2003, 12:33 AM: Message edited by: Pablo ]