Engine oil AMSOIL or Eneos

Have noticed on several times that when I went from Subaru OEM oil to Amsoil BACK to OEM that it runs much quieter and smoother on Amsoil.

But I run Amsoil signature blend in my vehicles. And I also push 15,000-25,000 miles per change.

I have seen my friends and family use amsoil for 25000kms each change and their cars do 200k- 300k without any engine issues.

I already added to engine oil and transmission. 5mpg improvement avg. already.

Switch to Amsoil products and go every 6,000. I honestly would go every 7500 with it if it was me driving that much.

Send your used oil to Blackstone or Amsoil for analysis and all of your questions about oil will be answered.

The best all rounder motor oils currently in the US are Pennzoil Ultra Platinum and Amsoil Signature, the latter you can run for at least 20k normal service or 15k extreme service.

I got better results from signature 5w30 at 11,200 mi than I did from Motorcraft “full synthetic(lies) at 4300mi. So I change my amsoil at 8-10k and my Pennzoil ultra platinum at 7500.

I have amsoil in mine. I went 7500 once. Im sure anyone can go 10k with amsoil but it will be dark oil when u change it out lol

Amsoil's biggest 'benefit' is a longer service life. Their additive pack doesn't break down as quickly, so you can run it longer between oil changes. However, if you're paying twice as much and running it twice as long, it's a wash and you're not gaining anything. When I was selling Amsoil, I had a modified 4 banger and a high mileage 24v that had both been running Rotella for the entire time that I owned them before switching to T6 when it was introduced. I pulled UOA samples every 1k miles, then switched to Amsoil Signature after 5k and did the same thing except I pushed the Cummins to 10k. Zero improvement in fuel dilution, wear markers, or carbon build-up. After seeing there was no real-world benefit, I stopped selling it. I won't market a product I don't believe in, let alone one that I see as an outright scam.