I've been using Mobil 1 quite a long time and I decide to not use it anymore.
My buddy (some of you met him few times) who is an engineer student at UofT researched on synthetic oils for himself and I jumped on it too later when he first told me about it.

Here are some infos.
The best sythetic oil is made of PAO and Ester molecules which does not include any conventional natural oil substances. Some of companies that uses PAO are Amsoil, Motrlube, Royal Purple and Redline(Ester).

These PAO based oils doesn't clog the oil filter with Carbon, last longer, lubricates better. A guy who is using Motrlube changes oil every 100,000km/3 years(yes 100,000km with filter changed reguarly)and when he send the sample of it to anylize it, it was still fine to use more. Too bad they only make 10W-40 and 15W-50. I emailed them to find out if it's a pure PAO or mixture of PAO and Ester.

Amsoil recommends to change it's oil every 25,000miles(40,233km) and Redline recomends to change the oil(basically highway driving) between 10,000 and 18,000mile(16,000- 29,000km). I found out Amsoil is mixture of PAO and Ester and Redline is just an Ester( they probably have PAO one available also).

But Ester is made out of ACID and Water. You don't want it in your street driven engine unless you always burn all the moistures in the engine before you shut it.

I don't know what Royal Purple is made out of. Probably PAO + Ester.
ok, now why I don't want Mobil 1. Mobil 1 tri-synthetic has PAO in it but only 1/3 of it is. The rests are 1/3 of hydrocarbon and 1/3 of crude oil. It's probably the best engine oil you can grab from Canadian Tire but kinda crappy for a Synthetic oil. It will still leave carbon in your engine. This info is based on their tri-synthetic. They came up with NEW Super synthetic now, so it could be worse or could be better. Look at the price change from last year and you decide.

Here is some good article on synthetic oil
http://www.squirrelpf.com/tech/oil.shtml
PAO oils, or a PAO blend are your best bet for street use, they provide excellent protection, are affordable and more stable than ester oils. Ester oils are made from an acid and water, which is perfectly fine if you can guarantee no moisture is going to enter the engine, unfortunately on the street the temperature fluctuations of daily driving creates moisture. An ester in the presence of water tends to want to return to its original form, an acid and water . Picture acid in your crank case – NOT GOOD! Ester oils are fine for racing and constant high heat applications that will not create moisture but it’s questionable about the stability for street use. PAO oils have all the benefits of an ester oil just not as good of viscosity index when used in extreme situations


Now, who's still gonna use Mobil 1?
Anyone have more info on these?

 

I'll stick with Mobil 1 because it's easy to get hold of and fairly cheap. I pulled my valve cover to adjust valve lash a few weeks ago and after 40k miles, there is absolutely no residue on any part of the valvetrain and nothing stuck to the underside of the cover. In contrast, there was some minor buildup under the cover of my 90k Civic that has been fed Castrol all of its life. By the time my engine would wear out anyway (200k-300k miles for a conservative estimate) the car will be long gone. Sure, those others are probably better oils, but Mobil 1 is more than enough.

 

Looking around on amsoil website they have 5w-30 and 10w-30, its about $6 a quart, I'm debating using this in my ZC. Fill it up with new oem filter, run it a little, drain it, replace filter again and go from there.

Edit : I do have a question though, when using synthetic, lets say you change your oil every 10k miles, how often do you change just the filter? I know its easy to just change the oil with the filter but if I'm shelling out $25 a change I might want to just replace the filter at 3k and the oil at 6k.


Modified by blah13 at 3:48 AM 4/21/2003