This is off of another web site(S2KI) and I find it funny how they talk up one oil and then in the same post say how they change it out after 3 to 5k miles.
"There's a little more to the drain interval with Amsoil than meets the eye. I'll give you a little background - then tell you the truth about the Amsoil 25k drain interval.
First off: I've been using Amsoil ATM 10W30 since my S2000's engine was broken in - but have been running ZRT 10W30 (as an experiment) for the past 10,000 miles. I am a huge proponent of the now dubbed "Signature Series" (ATM) 10W30 for a lot of reasons. Benefit to date: With 82,000 miles + on the clock my engine still has less than a 2% leakdown per cylinder (checked every 10K). The leakdown numbers are between 1.2% and 1.7% and have not changed toward the negative since the first leakdown at 35k (they actually improved ever so slightly - indicating the car was not quite fully broken in when I switched to Amsoil). My consumption has averaged less than 0.25 qt per 3,000 miles with ATM and less than 0.5 qt per 3,000 miles with the ZRT. I switched to the ZRT because it's a high ZDDP oil, which will give a little more protection to my crank thrust washers (I have a high clamping force pressure plate clutch). ATM has a relatively high moly content for anti-wear - ZRT has high phosphorous and zinc (ZDDP). I'm not worried about my catalyst - it's a Berk high flow cat.
My car has had two relatively high over-revs - one approximately 10,200 RPM early in the car's life (around 15k) and another more recently (73k) when a semi suddenly came in my lane and ran me off the road near Memphis while I was passing - that one was just under 10,000 RPM. No negative effects (although I had the intake retainers replaced with AP2 retainers as a precaution after the first over-rev. None were cracked).
Aside from the self-induced insults, my car sees 9k on a regular basis, I ran 4.57 gears for over half it's life, I'm currently running 4.44 gears (lower final drive ratios add wear and tear on the engine due to the higher RPMs), and I generally drive it like it was meant to be driven. The car is well maintained - but I drive the [censored] out of her.
- As for the 25,000 mile drain interval: If you drive a Prius, or another low-performance, standard-duty commuter vehicle under NORMAL conditions: then YES, you can use the 25k interval - as long as you use the Amsoil Ea series filter (which is made in either a 15k or 25k interval design).
*If you drive a vehicle with a HIGH PERFORMANCE engine (Honda S2000, for instance) then Amsoil directs you use the manufactures recommended drain interval. So NO, do not go 25,000 miles between oil changes - regardless of the oil.
A side note: the blanket statement that Mobil 1 is "Garbage" is not accurate (per se). Mobil 1 Extended Performance (EP) is actually a good motor oil. It's as expensive, or more expensive (if you're an Amsoil dealer or on the Preferred Customer Program - PCP) than Amsoil - and it's not as good as Amsoil ATM in testing... but it is a good motor oil. Standard Mobil 1, however, is NOT a "good" oil (IMHO and in testing) and has a terrible reputation of high consumption in AP1s.
The question is: are you lazy and don't want to bother ordering online? Then buy Mobil 1 EP. If you can think forward and organize your life in intervals greater than 24 hours (not necessarily me some weeks) - then either call or order online and get a better oil. The Amsoil PCP pays for itself if you buy a singe case of oil (12 quarts). So if you maintain your S2000 like I do (change oil every 3,000 - 5,000 miles; transmission every 1-2 engine oil changes; diff every 2-3 engine oil changes) then it's kind of a no-brainer - order a case of oil, 5 quarts of MTF and 4 quarts of SG 75W110 under the PCP and you will actually save a tiny bit of money over many of the popular store bought synthetic oils.
If you're switching to Amsoil from another oil - do yourself (and your car) a little favor and make that first Amsoil interval on the short side (1,500-2,000 miles). Around 10% of the old stuff typically remains after an oil change and you won't see the benefit of Amsoil until all the old stuff is gone. That won't happen after the first oil change."
If I'm going to pay for M1 or Amsoil or any synthetic oil I want to get the miles out of it before I change it out or I'll just get dino and go 7k miles.
ROD
"There's a little more to the drain interval with Amsoil than meets the eye. I'll give you a little background - then tell you the truth about the Amsoil 25k drain interval.
First off: I've been using Amsoil ATM 10W30 since my S2000's engine was broken in - but have been running ZRT 10W30 (as an experiment) for the past 10,000 miles. I am a huge proponent of the now dubbed "Signature Series" (ATM) 10W30 for a lot of reasons. Benefit to date: With 82,000 miles + on the clock my engine still has less than a 2% leakdown per cylinder (checked every 10K). The leakdown numbers are between 1.2% and 1.7% and have not changed toward the negative since the first leakdown at 35k (they actually improved ever so slightly - indicating the car was not quite fully broken in when I switched to Amsoil). My consumption has averaged less than 0.25 qt per 3,000 miles with ATM and less than 0.5 qt per 3,000 miles with the ZRT. I switched to the ZRT because it's a high ZDDP oil, which will give a little more protection to my crank thrust washers (I have a high clamping force pressure plate clutch). ATM has a relatively high moly content for anti-wear - ZRT has high phosphorous and zinc (ZDDP). I'm not worried about my catalyst - it's a Berk high flow cat.
My car has had two relatively high over-revs - one approximately 10,200 RPM early in the car's life (around 15k) and another more recently (73k) when a semi suddenly came in my lane and ran me off the road near Memphis while I was passing - that one was just under 10,000 RPM. No negative effects (although I had the intake retainers replaced with AP2 retainers as a precaution after the first over-rev. None were cracked).
Aside from the self-induced insults, my car sees 9k on a regular basis, I ran 4.57 gears for over half it's life, I'm currently running 4.44 gears (lower final drive ratios add wear and tear on the engine due to the higher RPMs), and I generally drive it like it was meant to be driven. The car is well maintained - but I drive the [censored] out of her.
- As for the 25,000 mile drain interval: If you drive a Prius, or another low-performance, standard-duty commuter vehicle under NORMAL conditions: then YES, you can use the 25k interval - as long as you use the Amsoil Ea series filter (which is made in either a 15k or 25k interval design).
*If you drive a vehicle with a HIGH PERFORMANCE engine (Honda S2000, for instance) then Amsoil directs you use the manufactures recommended drain interval. So NO, do not go 25,000 miles between oil changes - regardless of the oil.
A side note: the blanket statement that Mobil 1 is "Garbage" is not accurate (per se). Mobil 1 Extended Performance (EP) is actually a good motor oil. It's as expensive, or more expensive (if you're an Amsoil dealer or on the Preferred Customer Program - PCP) than Amsoil - and it's not as good as Amsoil ATM in testing... but it is a good motor oil. Standard Mobil 1, however, is NOT a "good" oil (IMHO and in testing) and has a terrible reputation of high consumption in AP1s.
The question is: are you lazy and don't want to bother ordering online? Then buy Mobil 1 EP. If you can think forward and organize your life in intervals greater than 24 hours (not necessarily me some weeks) - then either call or order online and get a better oil. The Amsoil PCP pays for itself if you buy a singe case of oil (12 quarts). So if you maintain your S2000 like I do (change oil every 3,000 - 5,000 miles; transmission every 1-2 engine oil changes; diff every 2-3 engine oil changes) then it's kind of a no-brainer - order a case of oil, 5 quarts of MTF and 4 quarts of SG 75W110 under the PCP and you will actually save a tiny bit of money over many of the popular store bought synthetic oils.
If you're switching to Amsoil from another oil - do yourself (and your car) a little favor and make that first Amsoil interval on the short side (1,500-2,000 miles). Around 10% of the old stuff typically remains after an oil change and you won't see the benefit of Amsoil until all the old stuff is gone. That won't happen after the first oil change."
If I'm going to pay for M1 or Amsoil or any synthetic oil I want to get the miles out of it before I change it out or I'll just get dino and go 7k miles.
ROD
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