Based on what metric?

 

Amsoil is not for everyone. If you want the absolute best you pay for the privilege. If you don't care about that then buy the cheapest synthetic oil you can find at Walmart.

Driving the same car for many winters using different oils.

 

I don't skimp on costs when they're justified. Without justification, the item becomes just another Giffen good.

Your opinion is noted.

P.S. - Walmart sells Castrol, which is the preferred oil of Audi. 5L for about $25 OTD. And theirs actually has ILSAC GF-6A approval. Don't let the Wallyworld sign disuade you from a good deal.

 

I really don't know all that much about motor oil but back in my drag racing days my nitrous infested LS1 sounded like it was running on gravel while on Mobil 1. Nobody really liked it back then. (no I didn't have the legendary piston slap).

When I switched to Amsoil per my mechanic's recommendation, it got nice and quiet. That was back in my college days (so a long time ago) ...I am sure both oil compositions have changed 10 times since then...

Since then, I've switched to Royal Purple. You wouldn't believe how many pieces of rotary equipment out in the refineries run on industrial barrels of that brand, so it inspired confidence.

I really don't know yet for my IS350...only have 1500 miles on it but when the time comes, I'll probably do Amsoil. (unless this nitroracer feller is right about the certification and it becomes problematic with the warranty. Personally, I have no idea.

 

Amsoil doesn't pay any car manufacturers for for the testing required to get the certifications, so they have none whatsoever (that I'm aware of, though I could be wrong). Again, not a deal breaker, but I'm not going to play WebMD with my engine like the folks over at BITOG.

I do have another vehicle that is out of warranty where I'm using non-approved oil. Don't want to be a hypocrite and obscure that fact. However, I'll be the first to say that I'm totally guessing as to whether or not it's worth the price, or that it's not actually harming my engine.

At the end of the day, you'd be hard-pressed to find a better oil or deal than Mobil 1 full synthetic when it's on sale at Costco. $30 vs $108. Is Amsoil really 4x better than Mobil 1? I doubt it.

 

My experience is the same makes the engine noisy.

 

Motul 8100 5W-30

 

Wrong viscosity?

 

I have seen some IS350 users 5W-30 to help with reducing oil consumption. Most Toyota/Lexus dealers near me use 5W-30 for older gen cars or cars that burn oil.

To be honest I might try using 5W-30 in my IS350 to see if it helps with the oil consumption if engine flush and 0W-20 PUP oil don't help.

 

Update -

After 3 OCI with PUP, my oil consumption has decreased. However, I have a bigger issue at hand - used a borescope to check the cylinder walls when changing the spark plugs and found scoring along the walls which is the reason why it is burning oil at high rpm. Some cylinders have it worse than others. At 183,000 miles car has taken a beating. Time to search for a used engine

Video of the scoring-

 

Mobil 1 by every account is not a fantastic oil. It sheers quickly and breaks down significantly over time.

 

I started using the new Valvoline Restore and Protect 0W20, they claim with continued use it can clean to like new condition. It’s a tall claim, it’ll be some time before there is proof as to their claims. Their marketing claim is luring, I’m going to continue on the Restore and Protect path and see where it ends with 5,000 mile oil change intervals. Car only has 64,000 miles, kind of low for a 7 year old car. But I will put a lot of miles on it.

 

Valvoline is good oil, I actually just put in Restore and Protect 0w20 in my IS300 to try. By all accounts looking at oil testing, the oil has a solid base and really nice additive package. I do 5k change intervals as well and use different oils. I have been using Amsoil and Pennzoil Ultra Platinum a lot and love those oils.

 

Thinking of switching to 5w-30

 

Those cylinder walls are done, sorry to see that. I see you mentioned the engine has 180,000 miles, seem like that type of wear is premature for a properly looked after engine.