I like Redline for one reason, they are the only American company that makes real synthetic oil. There is no ground oil in Group 5 oil, it is made from mixing an alcohol and an acid. They also use more molybdenum then any other company. Invest an hour or so and read the syn thread in my sig, most guys find it informational. Some of the info is dated because the oil industry is a fast changing industry, but there is a lot of knowledge from a lot of guys in that thread.
Amsoil "was" committed to group 4 oil, which also is much better then group 3 oil. However, like I was saying things change and there have been advancements in group 3 formulations so there are a lot of good choices. No engine oil will last in your engine and still protect your engine like Amsoil. We know this based on reading used oil analysis's and following the TBN (additive package number that shows the oil is still protecting against acid buildup), it is a 25k mile oil if you use a synthetic media filter in your engine! It is widely talked about that their premier lineup with a mix of group 3/4/5 oils.
An example of changing info may be if you were looking for an engine oil, if you read all of the oil posts you might opt for Penzoil Ultra instead of Redline or Amsoil, and that literally may be the best choice eventhough they are group 3. Not for a long oil change interval, but for low wear numbers.
But for gears and tranny's there are huge benefits from using ester based lubes, and there is only one American company that makes them. If you have any quetions after you read the syn thread, I'm sure guys like Syn or Myself will point you in the right direction. There are no brand loyalties between us, we just know what additive packages we prefer and then we pick an oil that matches what we want for our trucks.
