does Amsoil SS thicken with use?
- Thread starter Jeep J
- Start date
Was the viscosity tested before use? there's variation in the production, so 0.4 cSt either way is not uncommon. And there's variability in testing. I would consider that the same viscosity after use.
I believe oils with no Vll or with very high quality ingredients don’t shear. So the thickening is oxidative thickening which usually happens in extended oci’s.
dnewton3
Staff member
Generally the contributing factors which makes oils "thicken" from use are contamination (insolubles) and oxidation. These are typically unavoidable as the OCI matures, and in lower values they are generally harmless.
Don't confuse this with the effect of VMs; separate topic entirely.
Don't confuse this with the effect of VMs; separate topic entirely.
All oils will thicken over time due to oxidation. It happens to some quicker than others depending on the formulation. If you can control the oxidation rate you can control how fast it thickens. Amsoil is one of the most oxidation resistant oils on the market.
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At first no, then later yes. Much later on.....
Another instance of technical decision making on what is likely wholly insignificant data.
Much like "I put oil X in my car and got a .3 MPG improvement!"
Why not buy a thicker oil to begin with instead of hoping that an oil will get thicker in a good way?
Wish there was a 0W-25 available
There is, it's called 0W-30 or 0W-40.
I picked up a Mobil 1 0W-40 from Walmart shelf, shook it, it made a weird thicky sound so I put it back. My lil Jeep is not a Ram TRXThere is, it's called 0W-30 or 0W-40.
I picked up a Mobil 1 0W-40 from Walmart shelf, shook it, it made a weird thicky sound so I put it back. My lil Jeep is not a Ram TRX
Try Mobil 1. It's not as thick! lol
So you went from 25 to 40 and skipped 30? I'm guessing because it's harder to find 0W-30. I don't see much on shelves either.
Does your winter temperature range require a 0W oil?
There are lots of good 5w30s out there.
Nope, I live in Seattle. 35 - 45 degrees most days in winter. Do you think PUP 5w30 will flow fast and nice at 35 degrees? Or Mobil 1 Truck and SUV 5w30?
We live in the same area!
Even a 10W will do.
I use a good chunk of M1 EP 10W-30 because all my cars like it. Can't get it to burn in any of my cars old or new!
0W-30 in my Jeep. Covers cold starts and 250f oil temps when off roading.
Yes. Every oil does this due to oxidative thickening and soot/contamination loading. Oils that show a lower viscosity in UOA are doing this too. If an oil starts at 10.5 cSt and shows 10.0 cSt after 5k miles and no dilution present, it likely sheared down to 9.5 cSt (or lower) before thickening back to 10.0 cSt. Since HPL's oils don't shear, you only see the thickening.
15W-40 is enough for those lows.
15W-40 is enough for those lows.
Most 15W-40 oils are junk though. If in the API realm, I'll take a 5w30 or 5W-40 over a 10W-30 or 15W-40 regardless of temperature.
If anything, that only further proves the point I was trying to make.
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