I was listening to Pat Goss' radio show and heard him say that Amsoil is the ONLY real synthetic oil available. Is this true, or his he simply paid off by Amsoil?

If you're not familiar with Pat Goss, he is on "Motor Week" on PBS and has a syndicated newspaper column, as well as the radio show.

This is the first and only time I've heard anyone make that claim.

"Synthetic" oil is an almost misleading term. Synthetic oil can come from a number of differernt base stocks. Synthetic oil can come from a hydrocarbon base stock. To make a long story short, guys in white lab coats can select the best hydrocarbons that come out of the ground and create an oil fron that. This oil could never be created in nature, is entirely lab based, and therefor synthetic. I don't know where this guy get off saying Amsoil is the only true snythetic. Redline uses a polyol-ester base stock... which is petrolium based http://www.exxon.com/exxon_productdata/lube_encyclopedia/polyol_ester.html for a quick defination.
I took a quick look at the Amsoil website and could find nothing on their base stock... but the descriptions all over the sight say "100% synthetic". *opinion*Just another reason I really don't like the company... their website dosen't know anything, just like their sales people *opinion*

I would like to see what Amsoil defines as "true synthetic."

As far as traditionally, synthetic was defined as a Group IV base stock oil, which is limited to either polyalphaolefin (PAO), ester (some consider ester to be Group V others), or a combination of the two. However, many other manufacture use PAO based oils (as Amsoil concedes in their report as I read from their webpage) but Amsoil noted that many would change to Group III (which a few company have).

MrHorspwer (or anybody else interested), the issue, IMHO, is whether or not Group III (which is in reallity very highly processed mineral oil IMHO) is in the strictest sense "synthetic". Some oil manufacture sell Group III basestock as "synthetic," and the courts ruled in favor allowing such advertisement.

So should I not put it in my diff and tranny and get RedLine or RoyalPurple instead? Is it that big of a deal?

JR:confused:

Put whatever you wish...both are good oils. I use Mobil1 "synthetic" in everything....engine, tranny, and diffs. :D

Mobil 1 in trany gives me problems with second in cold weather!!!

If you plan to switch to AMSOIL synthetic motor oil, do not use their original formula. Go with their API certified XL-7500 motor oil instead. I tried their original 5W-30 in my RS for a few hundred miles, and I was getting a lot of loud valve train noises. They sounded more like bad rod bearings. I have switched over to Mobil 1 5W-30 synthetic, and no more loud clacking noises.

--
Richard

That's because there is no friction to mask the noises... I have it a little on my 2.2.

I've used all different grades of their product line. Even 0w-30 in the summer! No problems :D

Currently using xl 5w-30 and Subaru filter.

Roger

There's a good thread on tranny and diff. oils in the Maintenance forum. Synchro's need some friction to work quickly, so a lot of us run different fluids in the different boxes. The Subaru LSD is sealed, so it shouldn't matter whether you run something with friction modifiers or not. Some folks are reporting good results with the Redline oil in the transmission.

Ahm using Mobil1 5w30 right now. Changed oil at 3000 and no problems so far. Gets cold in the morning around here.:cool:

I have Amsoil 0W30 in my engine. Very happy with it so far, summer or winter. Have run it as low as 45 below.

I've been using Mobil 1 for about 15 years now - always had good luck with it. Plus you have the advantage of being able to find it just about anywhere.

The comment that Amsoil is the "ONLY" synthetic oil is simply bad information. Amsoil is in a group of lubricants that is slowly dwindling but they are certainly not the last manufacturer to incorporate PAO base stock for their oils.

Oil groups are broken down into 5 categories. Group IV and V are considered by many to be true synthetic while Group I-III are either "solvent refined" or "hydrocracked" mineral oils. Understand that there is nothing wrong with a Group III oil except that you are paying a very high price for a very highly refined MINERAL OIL.

Valvoline, Mobil, Amsoil and Pennzoil use Gp. IV (PAO) base stocks to formulate their oils. These companies all produce fantastic products.

Castrol (North American), Petro Canada, Shell (North American) and Chevron all use Gp III base stocks to produce their synthetic oils. These oils are fantastic also.

The difference here is that companies like Castrol and Shell are charging Gp. IV prices for Gp. III product. Chevron and Petro Canada prices are better and I have no problem with their pricing.

The main difference in oils is going to be the additive packages that are formulated for each company. some will have a superior base stock and a weaker additive while others will have weak base stock and strong additive package. I would strongly recommend using either Petro Canada (where available) oil if you choose a Gp. III or ANY of the Gp. IV synthetics if you're going to go with synthetic oil. Oil analysis is recommended to determine which oil is working the best for you. None of the name brand oils is going to give you any trouble but some people are anal about certain things and need every bit of information they can find.

Another strong recommendation is to do oil analysis before and after the installation of a K&N air filter. Watch for the increase of silicon in the oil. If a high jump is noticed then I would stop using this brand of filter. Keep in mind that oil analysis is used to see trends in contaminates so one sample is rarely enough to give you the data that you need to make educated determinations on products such as oil brand and air filter quality.

Sorry for the long post. I Hope some of this is helpful to you.

First, you have nothing to be sorry for--excellent post.

Second, what do you know about K&N filters that the rest of us don't?? Do they pass more dirt than stock filters?

Notice that he mentioned silicone and not dirt being the main problem with a K&N. If you over "oil" the thing, the silicone in the "oil" that is sucked from the filter can cause problems. Dirt will also possibly be a factor, but if you change your oil and oil filter regularly, this shouldn't be a huge issue.

FWIW, I don't think any motor oils are formulated with silicone as an ingredient. Silicone is used in some industrial oils to help combat foaming. Very TINY amounts are dispersed in the oil. Too much silicone is bad. ;)

Steve

I used to have a K&N air filter in my truck, but I stopped using it after an oil analysis showed a great amount of silicone and dirt in the oil. My truck came from the factory prefilled with Mobil 1 10W-30 synthetic.

--
Richard