Will switching from Synthetic to Dyno oil harm my engine?

Each to his own kink. Live and let live and all that.

May your seals swell alarmingly for Christmas :-)

Huw

I only use fully synth oil and swap it every 2.5-3K miles. But thats the manufacturers recommendation lol. Ouch. Bloody 3SGTE engine :D.

J

You are simply wasting your money changing it that often.

So what do you think that proves? That every car run on an extended oil change schedule will wind up a sludge pit?

My wife's car has run Mobil-1 10W30 for the past 205,000 miles (that's right, 215,000 miles total, was switched from Castrol GTX to Mobil-1 after the initial 10,000 mile break-in period.) The change interval is between 7000 and 10000 miles, most of the time closer to 9000 miles. Its gone as long as 15,000 miles on one fill a couple of times (my bad!) The engine is a 1993 Chrysler 3.5L SOHC v6, 215 horsepower, in a 1993 Eagle Vision TSi. I recently had occasion to remove the valve covers to install new gaskets. The cams, rockers, and valve stems looked like new. Not "clean," I mean LIKE NEW. As in "if you put these back in a parts bin, no one would notice that they were used unless they looked REALLY closely." I have observed the same with my 1969 Dodge 440 and my 1973 Plymouth 318 as well, although neither of them began their lives on Mobil-1 with ~10,000 mile oil change intervals.

Now, I could argue that Chrysler just builds a far superior engine to BMW (and in truth, I believe that is true when you take into account a lot of practical considerations for an everyday routine-driver type car- otherwise I'd own BMWs instead of Chrysler products). But I honestly think the Beemer got screwed by something else. Poor oil, a filter stuck in bypass mode, coolant intrusion into the lubricant, fuel contamination of the lubricant.... SOMETHING else. Not the oil change interval.

So? That sludged BMW isn't a diesel engine. UK and US DIESEL fuels are quite different and have a significant impact on DIESEL engine oil change schedules, but not so when comparing US and UK gasolines or lubricating oils.

I would say that the "pamperer" in this case is heartily deceiving himself. Valvoline Max-Life (in particular) was observed to have an excellent additive package WHEN FIRST INTRODUCED, but within a year or so, a number of key wear-preventing additives were sharply cut back. Its a 3rd-rate lubricant at best,\ now, unless they've put it back to the way it was. This was chronicled extensively on bobistheoilguy.com a few years back.

OK, now THAT I can agree with. Although I doubt that you'll find manyu of the group II/III hydrocracked base oils that are truly comparable to synthetics discounted quite that deeply.

And given what a tiny fraction of the cost-of-ownership buying oil is, spending $5 a quart is still way down in the noise.

snip

Every gasoline engine that overloads its oil with combustion byproducts and continues to operate in this condition will experience sludge accumulations. It's just a matter of time. There is nothing you can argue to the contrary.

What does that have to do with the main thrust of this thread?

The actual difference between UK and US diesel fuels depends on the State being compared.

Huw would disagree with you. The mineral oils that exceed the minimum API SL specifications abound in the UK. Go read some labels. See how often an API SL oil does NOT carry any diesel specs, let alone any MB specs or ACEA specs.

No I wouldn't!

The mineral oils that exceed the minimum API

They may do but only in their combined diesel rating, which marks them out as being superior. For instance, I use a mutifleet oil that combines API SL with API CH4 heavy duty diesel long drain specification. This is a much better oil than plain SL but SL is the only quoted petrol engine standard on the [rather large] can.

Go read some labels. See how often an

That may be a result of your market requirements which do not generally differentiate between performance levels above a minimum. In Europe it is common for manufacturers to require something better than an oil that is of a minimum acceptable industry standard.

Huw

If the car manufacture states you need to change it that often, 3k, and you don't, and something fails under warranty, they can refuse coverage. Now you really wasted money.

just a thought.....

tom @

Name a few motor cars that need 3000 mile oil changes and are still within the warranty period.

Huw

Then there was a failure to communicate.

That is my point (from a couple of lines up). Anyone shopping the automotive retail shelves in America will find mostly API SL with no diesel approvals at all.

Agreed. I wish alternative "above the API minimum" approvals were the norm here. As is, the only clues you have are the infrequent diesel designation (often AFTER the gasoline designation) or the infrequent vague reference to ACEA. Otherwise, you buy a fleet diesel oil. Of course these never have those Energy Conserving approvals or pissy viscosity numbers.

Oh fercryinoutloud! Its quite easy to find diesel-approved oil anywhrere in the US. Both synthetic and conventional.

My entry into this discussion came about because a picture of a sludged-up GASOLINE engine was used to imply that the "reality" as opposed to the "theory" of extended drain intervals would inevitably lead to that kind of thing. It does not.

Or you can read the oil analysis web pages. The fact that US-marketed oils are not MARKED above the API standard does not in any way imply that many oils sold in the US do not indeed exceed those standards by a wide margin.

Wal Mart has carried Shell Rotella T Synthetic for a few years now (alongside the non-synthetic Rotella, Delo 400, and Delvac 1300). It may also carry Mobil 1 "Truck and SUV" that is widely believed to be rebottled Mobil Delvac 1 (spec sheets look very similar, and the Mobil 1 "Truck and SUV" does have the API CI-4 rating).

The one at

?

I agree. Most standards met by an oil are not printed on the can and can only be found in more detailed literature and their product data sheets. It should be noted however that there seems to be greater detail readily available in Europe where ISTM there is a greater appreciation generally of oil gradation as opposed to most Americans [on Usenet at any rate] who seem to appreciate only a crude difference between mineral and synthetic, while not appreciating that for specific applications a particular mineral oil could be more suitable than a particular synthetic depending on the standards met by them. All I tend to hear is the question 'is synthetic better than mineral?' not 'is GM long life spec oil better or broadly compatible to BMW long life spec oil and how do these compare with VW506

01?' or similar question, as should be the case in a sophisticated discussion.

The only American that I have ever observed to wish to know anything above a basic level about oil is Philip. Obviously there must be a huge knowledge base within the oil industry over there but if Usenet is representative then most opinions here on Usenet are nearly baseless, or based on conjecture or tradition or with an exaggerated importance given to base oil type with little regard to the *standards* met by the end user product. Indeed, I feel that most Americans think that I am from another planet when I post about

15000 to 20,000 mile oil change intervals being commonplace. Maybe they think that I must mean 1500 to 2000 miles. Others seem to draw the conclusion that I am trying to get them to change their Toyota Camry's [for instance] oil at those intervals, whereas in fact I advocate changing at the manufacturers recommended intervals while pointing out that they could use a better oil to achieve this with an added safety margin or that an interval might well be specified for an easy life in a geographical area.*** This might not even mean changing to a synthetic oil or even changing at all if their present oil is more than adequate. Another gripe, while I am about it, is that 'more than adequate' is often taken to mean that there could be some gain from using 'something better'. In most cases there is just no advantage from using an oil that is just so much better than needed or specified by the engine manufacturer. ***It would surely lead to an easier and less controversial life for European manufacturers if, in the American market, they followed local tradition and had an initial oil change at 500 miles and a regular change every 3000 miles thereafter. No one would comment on this one way or another. Instead they choose not to compromise and use appropriate monitored intervals as used in Europe. They invite, in a way, the occasional sheep who has a strong opinion, to find pictures of an engine overwhelmed with sludge, regardless of the true story behind the picture, to rubbish the superior technology and reaffirm the 3000/5000 mile status quo as they see it. Perverse human nature in action.

Huw

Steve. This thread has evolved a bit higher than you can appreciate right now. Sit back and learn the nuances of API oils having no diesel designation, fleet oils, and European ratings.

It does lead to sludged engines. The 'extension' is by degree. Is 25k miles "extended"? How about 15k miles? Maybe 40k miles? Use determines the interval ... not your abitrary choice.

You are woefully ignorant of (for example) Mercedes Benz oil rating system and how various API SL rated oils measure up when tested above API minumums. Sit back and shut up while Huw educates you ... if possible. I'll let you have the last word.

I stand corrected. Mobil Delvac 1 is the synthetic whereas, Mobil Delvac

1300 is a conventional oil.

The Mobil Delvac 1 is very rare in truck stops as is Shell Rotella synthetic.