I've searched and found nothing really on Amsoil here. I have read that Amsoil and Mobil 1 are the only truely synthetic oils and Amsoil is better than Mobil 1. Is anyone running Amsoil. It cost about the same as Mobil 1. I also wondered about Amsoil's 25,000 mile or 1 year change interval. Should I go with Amsoil a regular nissan filter(~$4) and change every 3,000 miles even though Amsoil says it will last 25,000 or 1 year? Or should I go with Amsoil and an Amsoil filter($13.55) and get some more miles out of it like maybe 6,000? If it's better than Mobil 1 and only cost $.80 more a quart then I think why not go for it. Any suggestions or opinions would help.

 

Well, I have read a lot of info on other sites about this. Really, I am a bit undecided, and I am down to picking these two as well. It comes down to preference from what I can tell. From what I have read, the Amsoil is better only when you plan on extended oil drains. So it does have better life, although the mobil 1 is good in itself.

To me, both are about equal, except that mobil doesn't have the guarantee like amsoil does for extended drains. If you want extended drains go with amsoil, otherwise mobil. In our car, and the way I drive, I am leaning towards amsoil, although I is much harder to find and a little more expensive.

 

Based on what I've been told by a knowledgable mechanic, your wasting your money on synthetic oils if you still change the oil every 3,000 miles. You will get no added life out of your engine versus regular oil but you will spend alot more money.

The whole point with synthetic oils is to go longer between oil changes with no additional engine wear.

The concept that synthetic oil extends engine life is only true if you don't change your regular oil every 3,000 miles.

That's the way its been explained to me anyway.

 

I have been using Amsoil for 4 years in my Harley,over 40k on it so far, harley recommends oil changing every 3k miles,but with Amsoil, I change every 7500k, i have done an oil sample each time, no noticeable metal,oil was really clean. When I change cams, cam that was replaced looked brand new. I recommend Amsoil. Will use when my first change is due. check there website
amsoil.com.

peace

 

While I am sure the mechanic knows his engines, this is just not true. Syns take high and low temperatures better and overall they have better performance characteristics. This comes in handy in FI applications.

Also, its not that synthetics necessary clean better, however they are generally more resistent to heat and oxidation, so they degrade less than average quality petroleum oils and leave fewer sludge/varnish/carbon deposits.

So, yes, they are better in some situations, depends on how you drive your car, your climate, among many other things. I will be changing to a syn in my next oil change in a few days cause of these reasons.

 

Rodney,

I may be missing something but it sounds like we are saying almost the same thing. As you point out the synthetic oils do not degrade as fast, especially under stresssful conditions. This may be a large advantage if you drive your cars very hard.

However, under normal driving conditions , regular oil does not degrade at 3,000 miles and does not leave any more deposits than synthetics.

Therefore, use synthetics if your redlining your vehicle all the time or if you want to go longer between oil changes.

I would be very interested in additional points of view on synthetics versus regualr oil.

 

Yeah, Scott, but from your orginal post, I got the impression that the mechanic had said that the ONLY reason you would want synthetic is for extended drains. But your last post cleared that up a bit.

It really depends on how you drive, where you drive, and what you are looking for out of your vehicle. As a chemical engineer, I will be using synthetic cause I do drive my car pretty hard on occasion. But to each is own.

 

I'm using Amsoil ASL 5W30 (note that there are quite a few different Amsoil formulations) and will be changing it in the 6,000 to 7,500 mile range. Is it really better than Mobile 1? I can't prove it but I like that Amsoil gives a lot of technical info and actual wear test results. I couldn't find any other oil company willing to do the same. I am using the OE filters at the moment but will probably change to something better. There was a good thread a while back on oil filter construction, I'll have to search for it before I buy any more. I remember that they really slammed the OE and Fram filters.

 

Well, Amsoil and Mobil 1 come from the same base oil, Amsoil has been buying from mobil for years and years. The difference is in the additives. Amsoil does have better additives, which does make it last longer. Although, I am not one to test their ads for 25,000 mile oil changes, they do last for quite a while. I have Mobil 1 in my car right now, but I will be trying Amsoil sometime in the future. "Better" is a real subjective term when it comes to oils, it totally depends on application.

Now there are many other synthetics out there that are worth checking out. Redline and Royal Purple are among the true group 4/5 synthetics that are worth looking into. Redline is quite good, if you really, really run your car hard.

 

I use Amsoil 5W30 in the crankcase and Amsoil Series 2000 gearlube in both the MT and diff.
I previously used Castrol Syntec and Mobil 1.
The Amsoil is superior. The difference with the gear lube is unbelievable, in terms of shifting. I will probably put between 7K-8K per year on the car- it is stored winters- and I plan a change at the end of each season.
Do yourself a favor and get a better oil filter- like a K&N HP-1008.

 

Has anyone used the mobile 1 synthetic oil filter? If so what part number was it?

 

Has anyone used the mobile 1 synthetic oil filter? If so what part number was it?

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