Amsoil on 20wt. oils

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Nov 16, 2002
I emailed Amsoil to ask them a question regarding 20wt. oils and whether they prefer the oil thicken or thin out of grade if it does occur. This kind of relates to my other post regarding an oil for a C5 Vette. My response came from Jim V. (forget his last name, i left the email at work). He said basically the same thing everyone here has been saying.

He said 20wt. oils came about for political reasons..EPA etc. Ford and Honda jumped on it and in part, it forces owners who don't know any better to take there car back to the dealer to get serviced bc these viscosities are or were hard to find. He also said Amsoil's XL line of 5w-20 doesn't sell very well and that most costomers feel safer with a 30wt. oil. He did mention that he wouldn't feel to good about an oil thinning into a low 20wt if it starts at or near 20wt. to begin with. I mentioned to him that a particular brand (Mobil 1) tends to start a low 30wt. oil. Now Mobil 1 is a great oil and analysis proves this, but I think for High End cars a heavier Redline or Amsoil is more ideal, unless you change the oil 3-5k miles before it thins out. I'm not knocking M1, and they don't always thin out, but I'd feel more comfortable using a heavier oil rather then thin, especially if I owned a performance car. Why settle for a lighter wt oil bc the EPA wants better fuel efficiency? Some engines 20wts. will do well I'm sure and be perfectly fine, but for F-150 trucks I would not go with a either. So in the long run, if the US ever goes to longer drains, like Europe, the trend will have to be to go back to 40wts. I imagine, unless the technology allows a 20wt. to go very long distances.

He also mentioned that Amsoil doesn't make a long drain 20wt. oil bc they wouldnt want it to thin any lower, hence protection loss.

[ March 26, 2003, 05:22 PM: Message edited by: buster ]
Hasn't the US already gone to longer OCIs? Isn't Toyota here up to 10K and Ford has extended longer as well in the last 10 years, both with 20wt oils.
Holy thread revival batman
Originally Posted By: OVERK1LL
Holy thread revival batman

I just noticed that!!.
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I wonder what their answer to that question would be today? I bet it would be a lot different.
Yeah, A LOT has changed since Buster made that post...(I'm suprised no-one commented on it back in 2003 - the first response is from a couple of days ago!)

Amsoil now makes, what, 7 types of 20-weights? And their SS line has 2 long drain 20-weights that we've seen go 20k+.

One thing that IS interesting is that when Amsoil re-formulated SSO 0W-30 (from TSO), they made it a VERY thin 30-weight - 10.3cst @100C, and 56.56cst at 40C....I wonder if that was to help the people who needed a 20-weight, but couldn't deal weith using one.....
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