Synthetic Oil: When to switch?

OK….. I have heard all the good stuff about the Synthetic motor oils and I have always heard that you are supposed to break in a new motor on Fossil oils, and then, after “X” number of miles or hours, you can make the switch to the synthetic.
My wife’s BMW, and the new Corvettes (and maybe some others) come from the factory with 0 miles and the Synthetic oil is already in them, and I was wondering if you really need that break in period?

What rules are you guys following in regards to the Fossil/Synthetic usage?


Krash
Dallas TX

yep and 1ce you switch, can't go back. Me personally, I don't like the idea of synthetic oils, the fact that ice you use them, you cannot go back, dosn't seem right. The fact that some new cars come with synthetic is understandable, the engines are probably broke in and run tested with regular oil, then changed to synthetic.

If your engine requires a break-in period, I'd change once the rings have completely seated (2500 miles?). Change it again at 5000 miles and every 5000 miles after that. If the car came with the synthetic alreay in the car, I would assume the factory breaks-in the engine on a stand before installing the engine.

The only reason to start off with dino oil is that synthetic can do too good a job and hinder the abilty of the rings to seat. On a fresh rebuild, do as your builder suggests, and if you rebuilt it yourself, I'd start with dino and then switch.

My Ranger has 135,000 miles on it, and it doesn't leak, doesn't burn oil, and looking into the valve train area, it's as clean as a baby's bottom. When the dipstick is pulled, the oil at the end of a 5000 mile cycle looks almost as good as the new oil going in.

I've used nothing but Mobil 1 (5W-30) and have never had a problem. I'm sending the oil out to be anylized at 150,000 to see what the microscope can see. While it costs 3 times the cost of dino oil, I just consider it cheap insurance. And yes, I'll use it in my Studebaker (10W30).

From the Mobil 1 web page:

Can different synthetic motor oils be mixed together?

Mobil 1 is fully compatible with conventional motor oils, semi-synthetic motor oils and other synthetic motor oils, should it be necessary to mix them. However, it is important to note that the superior performance of Mobil 1 will be reduced by diluting it in any way

All of the other synthetic oil brand web pages agree that the oils can be mixed. They do warn that any additive ingredents may be compromised by mixing oils....duh.

Not mixing synthetics with dino based oils is an old adage from when synthetics first were introduced.

Mixing the oils isn't a problem. It's what happens with some of the seals (depending on material) when switching back to dino. While it may be coincidence, I've seen enough cars sprout little leaks here and there after the change over to question it.

As for oil compatibility, this is a nonissue. Some companies like Valvoline sell 'blended' oil that are half synthetic and half dino. Why anyone would want this, I don't know, but....

synthetic oil = Here is a little long winded article but very telling. With the exception of a few brands you ere getting SCREWED!! Read this to learn the games being played. This was posted by another and I copied to send it out but references were provided. Jeff C

Interesting tidbits on this topic:
Synthetic Motor Oil Gets All New Semantics (first published by Patrick Bedard of Car and Driver)

Now that the meaning if "is" has gotten so slippery you need to grab it with both hands, we'd better keep an eye on longer words, too.

One's already got so squirmy on us- "synthetic," as in synthetic motor oil.

Most guys know two things about synthetic oils. First, the price is three to four times that of conventional oils. Second, they're not real oil, not made from crude.

News flash: Scratch that second part. Now motor oils derived from crude may be labeled "synthetic." But they still cost over four bucks a quart.

Bait and switch? That's the obvious conclusion. Except in this case the advertising ethics people have given their approval.

Here's what happened, according to a detailed account published in the trade magazine Lubricants World. Late in 1997, Castrol changed the formula of its Syntec "full synthetic motor oil", eliminating the polyalphaolefin (PAO) base stock (that's the "synthetic" part, which makes up about 70% by volume of what's in the bottle) and replacing it with a "hydroisomerized" petroleum base stock.

Mobil Oil Corporation, maker of Mobil 1, "Worlds Leading Synthetic Motor Oil," said no fair and took its complaint to the National Advertising Division (NAD) of the Council of Better Business Bureaus. NAD often arbitrates between feuding advertisers on their conflicting claims.

The notion behind synthetic motor oils as we've known them is an elegant one. Instead of relying on the cocktail of hydrocarbons contained in crude oil, why not go into the laboratory and build the perfect base stock from scratch, molecule by molecule, and builds it till it gets 10-carbon molecules, then combines three of those to form PAO. The result is a fluid more stable than the usual base oils derived from crude. It keeps flowing at low temperatures. It's more resistant to boiling off, and more resistant to oxidation, which causes thickening with prolonged exposure to high temperatures.

Still, there's more than one road to the point B of improved stability. Petroleum refiners in recent years have learned how to break apart certain undesirable molecules - wax, for example, which causes thickening of oil at low temperatures- and transform them by chemical reaction into helpful molecules. These new hydroisomerized base oils, in the view of some industry participants provided properties similar to PAO's but only cost half as much," Lubricants World reported.

The argument before NAD tiptoed around the obvious- does the consumer get four bucks' worth of value from each quart of synthetic oil?- and plunged straight into deep semantics. Mobil's experts said "synthetic" traditionally meant big molecules built up from small ones. Castrol's side held out for a looser description, defining "synthetic" as "the product of an intended chemical reaction."

What do unbiased sources say? It turns out that the Society of Automotive Engineers (SAE) and the American Petroleum Institute (API) both have technical standards covering motor oils, and both of these organizations in the '90's backed away from their old definitions of "synthetic," leaving lots of room for new interpretations.

In the end, NAD decided that the evidence constitutes a reasonable basis for the claim that Castrol Syntec, as currently formulated, is a synthetic motor oil, said Lubricants World.

The obvious question now: Has the term "synthetic motor oil" been opened up to the point that it no longer means anything? Maybe. But here's a better question: Did synthetic ever mean what we thought it meant?

"Great oil" is what most guys think it means. "At that price, it's gotta be great stuff!"

Okay, but how great? Your cars manual tells what motor oil you should use, and with few exceptions, that description will consist of only two specifications. One is for viscosity, such as 10W-30; and the other is for the API service grade, SJ being the current one for gasoline passenger cars.

The buck-a-quart multi-grades meet these standards, as do the synthetics.

The synthetics, on the back label, claim compliance with more standards, but even if you know what they mean, they seem beside the point for U.S. passenger cars. For example, should you care about diesels if you drive a gasoline burner? API service CF is the oldest of the current specs for light-duty diesels; some synthetics list that one. Synthetics may also list ACEA A1 and B1, which are European specs roughly equivelant to API gasoline and diesel specs. The Europeans grad their oils by level of performance, so that A2 and A3 are tougher specs than A1. Same for diesels. Usually the date of the spec is omitted, but A1-98 is newer than A1-96.

Completely absent is the one performance claim that would have some real meaning for all of us- some indication of longer oil life. (except for AMSOIL which clearly states 25,000 miles/1-year or 35,000 miles/1-year for their Severe Service 0W-30 synthetic). Automakers hold synthetics to the same oil change intervals as conventional oils. And the oil companies, promise even less. "To give added protection and life to your engine, change your oil every 3000 miles." This same language appears on the back of both Penzoil Synthetic and conventional oils. Valvoline synthetic makes a similar recommendation. (commentary: Since 1972 AMSOIL is the ONLY synthetic oil manufacturer in the world to guarantee 25,000 miles or 35,000 mile oil change intervals and utilizing full PAO synthetic technology exclusively).

Synthetics do get one unambiguous endorsement: Corvettes, Porsches, Vipers, and all AMG models from Mercedes-Benz come with Mobil 1 as the factory fill.

Most synthetics mention GM 4718M in their list of claims; that's the unique spec created by General Motors for Corvette oil. It's a high-temperature requirement that tolerates less oxidation (thickening) and volatility (boil-off) on a standard engine test called Sequence 111E according to engineer Bob Olree of GM Powertrain. (note: AMSOIL 0W-30 far surpasses GM's 4718M spec).

But don't expect to learn such details on any label (again, except for AMSOIL which clearly states test results on the back of every bottle of Series 2000 0W-30 and 20W-50 synthetic). Mobil 1 at least uses straight forward declarative sentences. Most of the others read as though they were written by a lawyer looking for an escape clause. Why else would the following claim be so rubbery? "Penzoil Synthetic motor oil is recommended for use in all engines requiring ILSACGF-1, GF-2, API SJ, SH, or SG, and in engines requiring oils meeting GM 4718M." Okay, but does it actually pass those standards?

"Yes" says James Newsom, Penzoil's motor-oil product manager.

Castrol Syntec, on its label, "exceeds" every standard it mentions. Hmm. Now that the meaning of "is" is in play, I have to wonder, does Syntec meet those standards as well?

"It does" says Castrol's Julie Ann Oberg. While I have her on the phone, I ask if there will be a Syntec price reduction now that the lower-cost base stock has been substituted for the old synthetic. She says no.

synthetic oil has been around for decades.research and development for jet engines for an example.amsoil pioneered the stuff for us the motoring public.mobile 1,castrol and all of the dino companys have their brand of junk out there.royal purple,amsoil and red line oils are true synthetics for us power crazed motoring public.they beat the dino boys hands down period.end of discussion!!!increase in miles per gallon.almost eliminating all friction.less friction more power.extended oil changes.in the coarse of one year and that includes filter changes every 3 or 4 thousand miles.the difference in out of pocket costs are very close.do not put it in any unbroken motor unless its built like drag strip motors.who by the way tear down and rebuild as they are staging for the next run.they to my knowlege all run it. quarter mile pro racers run synthetics.performance gains vary engine to engine but they all run faster,cooler etc. etc. and some make more than one pass before changing oil.i personally run a mildly built 455 olds in my 1981 caprice 2 dr coupe.i've owned about 12 years now ,got 100,000 miles on it ,use no oil and my motor still screams, coupled with a built turbo 400 and this heavy chevy---well--- i'll put it this way many times at stop lights they all ask the same question what do you have in that car.i smile and say it came with an olds diesel.stock low compression or trigger pull engines all benefit from it.oh and don't use it if your leaking oil or a loose engine or yada yada.it works people and its gaining popularity buy and try.you will be somewhat pleased.and i'am just a hotrodder doing my own thing i work for none of the company's mentioned

i failed to mention that some racers use dino oils i believe but only if they are a big sponser ,john force castrol for instance.true synthetics will pour at extreme cold temps. and will take the heat where mobile 1 would turn to carbon.dino oil is pushed by our friends the oil companys and we all know they would never lie???to us uh right or maybe or. they are supposed to be our friends.lets see no new refinerys since the 70's during jimmy carters president days.bragging right now about the huge profits they are enjoying.and with this latest storm katrina.we will see gas here in oregon over $4 bucks a gallon.nope i'am sure of it they lie to us.wow what a reality check.hey royal purple works increases gas milege etc. my big chevolds is proof to me and i have been using it for over 2 years,in my trans my rear axle etc.hey if you can buy a better car uh i mean uh.dino oil brain fog.okay send the hate mail my shrink says i can pretty much handle it just don't put that olds in gear by by

Lots of great info Jerry, thanks!! I've been using Mobil ! for a long time, very pleased with it. An engine does seem to break in a bit quicker with fossil oil.

Fuel prices are really terrible, I hear Hawaii capped theres at $3.00 per gallon. I had to go to Sioux Falls yesterday, when I left here at 6AM the price of gas was $2.89, when I got home at 11Am, the price had jumped to $3.18. Seems the station will make quite a profit on the fuel they allready had underground!!!! It just doesn't seem right. If I have 200' of tubing in the rack that I paid $2.00 a foot for and my supplier told me that when I bought more the pirce would be $4.00 then it would be ok for me to charge the customer $5.00 a foot because it was going to cost more when I head to replace it???

In the northern states this winter for people on fixed income and the poor it is going to come down to a choice of should I buy groceries or pay the heating bill???

AMSOIL and Break In on New and Rebuilt Engines

Q. I heard that new cars require a break in period with petroleum before you switch them to synthetic. How long should this break in period be?

A. AMSOIL Synthetic Motor Oil can be used during break-in trouble free. In fact, vehicles such as Dodge Viper and Chevrolet Corvette come factory filled with synthetic oil.

Since most new vehicles come filled with petroleum oil, it only makes good sense to change to AMSOIL at the first scheduled oil change interval. New engine components generate high levels of wear metals and can contain contaminants from assembly. By allowing the engine to operate with the petroleum oil until the first oil/filter change interval, the wear metals and contaminants are removed prior to installing AMSOIL.

While the Viper and Corvette are factory fill with synthetic, the engines are broken in at the engine plant. They don't say how they break the engine in or what oil they use to do so. As an engine isn't typically abused abused during break-in, dino oil should work fine and help the rings seat that much sooner.

But, I'm still a big believer in Mobil 1. When the new engine is ready to be run, the first oil will be dino, then Mobil 1 from 2500 miles on.

Okay, so now I'm totally confused. Just recently we replaced the head gaskets in the Cobra. When we got it apart we found two of the roller rockers were in pretty bad shape. Someone who knows more than I do (and that's not hard, most everyone knows more than I ) told me it's because I've been using synthetic oil. He said; "If you use the car on a regular basis synthetic is best, BUT, if the car sits for two or three months (as the Cobra does over winter,) synthetic "drains" too well, and in the crucial start-up period, until oil pressure builds, you're running metal to metal, with no lubrication at all. Mineral oil "clings" better, and will leave a film over the internals."
So now I'm using mineral oil. Was he right? Did I do the right thing?
johnboy

i think somebody is blowing smoke up your butt. far as i know synthetic oil has the best #'s on everything. i've use AMSOIL for the last 20 yrs. and its done ok by me. my cars set more than i driveum. oil is the least of my worries. :HMMM:

Yep,I think you may be right. So next oil and filter change, I'm going back to synthetic. Thanks.
johnboy