Synthetic oils

5.0_GT_kid

Dirt-Old 20+Year Member
Apr 18, 2004
1,155
1
39
Largo, Florida
So I have a question here I hope some of you can answer. Over the years I've read alot about Synthetic oils and it seems that Amsoil, Mobil 1 and Royal Purple are the favorites, with Amsoil being the top dog.

My question is, what makes Amsoil (or any other brand for that matter) better or worse than another brand of synthetic oil? Is there any kind of proof as to which brand is actually better, or is it a preference thing?
 
  • Sponsors (?)


The main difference is whether they use a Type 3 or Type 4 base. A Type 3 base synthetic is petrolem formulated, where Type 4 bases are chemically formulated. Mobil I use to be a Type 4 and recently went to a Type 3. Amsoil & Royal Purple still use a Type 4 base whereas Mobil I does not. Tests have showed there is no difference between the two bases other than seal swelling and distortion, but the true synthetics have been crying foul as they are more expensive to produce. Ther is a ton more info on this subject, but I tried to give you the Readers Digest version.
 
Differences in the various oils (in addition to Gp III or IV stock) is how much PAE and PAO they have. Also there are differences in the add packs.

Bottom line is that any of them will probably be overkill for most peoples' application.