Quote Originally Posted by Packy View Post
Not all synthetics are equal. Mobil 1 is a group III which is actually NOT synthetic but highly refined crude. ALL Dino oils will sludge. Amsoil is a group IV PAO, redline and most Motul oils are group IV. IV and V are the only true synthetics. Penzoil ultra euro has some group V on it, much better than Mobil 1.
Incorrect:

1. Different grades of Mobil 1 have different percentages of the various basestocks. Look at the MSDS if you don't believe me. M1 0w40 has group II, III, group IV, and group V (as alkylated napthalene). This is the case with any name-brand synthetic. You have to use a mixture of group II through V for optimal performance. The specific percentages of each are often not disclosed because it is proprietary.

2. Group III is synthetic, period. The myth that it is not needs to die.

3. Dino oils do not sludge. A modern dino oil will contain some synthetic content anyway, so the line is blurring there.

4. Amsoil sells oils of various composition, such as group III, IV, and V. Most of them are a mix of those, like any other oil. You have bought into the marketing hook, line, and sinker if you believe their stuff is not group III.

5. Most Motul oils are not group V, they are mostly group III with some IV and V mixed in at varying percentages. Again, look at the MSDS if you don't believe me. Only the 300V grade is high in group V content. Red Line is group V but contains group II - IV for various reasons, such as combating seal swell and as an additive carrier.

6. "Group IV and V are the only true synthetics" is flat out wrong (see #2). The newer "group III+" stuff, such as Visom and XHVI, actually surpass group IV and V in many areas.

7. Only the 5w40 grade of Pennzoil Ultra Euro contains GTL, which is a competitor to Mobil's Visom. It is not necessarily "better", just different.