Ok, here's one more...take it as you wish, just relaying a conversation:

When I ran over to the dealership yesterday to sign my title that had come in on my trade-in, I had a talk with the service manager whose been servicing Mazdas for "over 15 years". We spoke at length (I had met him previously servicing another one of my cars) and so I finally asked about synthetic vs regular oil, and I got the standard, "Mazda recommends regular, but whatever you feel better with." Then he immediately said, "Synthetic will not void your warranty". I said, "Ok, what do YOU recommend?" He said, "I'll put synthetic in at your first scheduled oil change" with a BIG smile!!!

Also, he said synthetic is much better on the new rotary engines (and most any engine for that matter) and there are no longer seal issues. He also said that I could even start adding synthetic now when the oil gets low (I kinda looked at him on that) and he said no problem until I went to a full synthetic oil change. He said it will NOT hurt the motor, has seen several high-mileage rotaries that run BETTER on synthetic with no problems. Another tech who was standing nearby came over and echoed the same thing.

Another comment: "There really isn't that much difference between most standard motor oils amongst themselves, meaning standard vs standard. With a rotary you're going to be burning oil anyway. Synthetics amoungst themselves are very similar... BUT... they don't break down like regular oil. Wouldn't you want the added protection, especially if you plan to put a lot of miles on it?"

Finally, I asked about Amsoil. He thought it was a good product. They use Castrol on their services, but "You can use ours, or bring your own".

So I guess, for me, my question on oil has been answered and what I'll be using...

Russ

 

Rotary God(s) is pleased.

Not sure if my dealership would be willing to put synthetic in there for me, I'll have to ask next time I'm in.

 

Btw, mazda is giving their same canned response for the MPS 6 as well. Turbo I4 and they're telling the dealers to only use semi-synthetic...even though it looks like its got full syn from the factory.

Audi/VW turbo turds anyone?

 

Our 1.8T is running dinosaur juice, as far as I know. Then again, I'm a little less picky with her because she's getting old...

 

I guess you missed the giant class action lawsuit over the whole dino juice in the 1.8T's.
http://www.autosafety.org/article.php?scid=151&did=963

426,000 Audi A4 and VW Passat's Effected.

They were forced to extend engine warranties on certain make/models which had a higher occurance then others.

Basically the engine builds up sludge and "turbo turds" if you run non synthetic oil in for the recommended service intervals.

The turbo's cook the oil, which coagulates in the lines, causing partial blockage (akin to cholesterol in arteries). This in turn can cause both turbine and engine failure, generally after the warranty period expires.

The solution to this problem is either more frequent oil changes, or swapping to a full synthetic oil stock, which can handle the temps associated with a turbo based engine.

The german recommendations for the 1.8T engine are actually incredibly specific now because of the sludge issues. The latest standard requires an oil which is at least Group IV (Full synthetic, not refined group III stocks), and has an HTHS of at least 3.5. (Spring Edition Audi Quarterly 2005). I might actually have that article if you want it scanned. (I'm a member of the audi club cause they host bad *** racing events)

Basically if you don't follow the spec's to a key, there is a very high likelyhood of the engine being damaged beyond repair.

Because of these issues, and the lawsuits, Audi and VW now REQUIRE the use of synthetic in the 1.8T engines to fullfill the manufacturer vehicle warranty. Not only that, but it has to be a high quality syn (No group III fakers!), which meets or exceeds the Euro spec as outlined in the letter.

Here's the letter that was mailed to owners.
http://www.autosafety.org/uploads/ph...WOilSludge.pdf

Audi Owner Letter
http://www.autosafety.org/uploads/ph...iOilSludge.pdf

Basically this whole (extended service interval) kick has caused billions upon billions of dollars in damages. People tend to follow the longer intervals, while running the standard oils, which breakdown far before the actual changeover. Additionally in the turbo cars, the dino oils break down incredibly quickly due to the heat of the turbo (oil runs through the turbo to cool it), and quickly disentegrates into unfriendly goo. Mercedes, Audi, VW, BMW, are all now dealing with these non synthetic warranty issues.

If you've got a turbo, you should be running full syn, no if's and's, or buts.

 

My son used the recommended syn oil in his 3 series BMW at the recommended 15,000 mile interval, I told him not to go beyond 10,000, I recommended 7500 but he went by the manual 15,000. Twice he began to get valve tap noise at about 14,000 miles due to sludge, the oil filter was becoming blocked. I have had 4 different cars that have reached over 175,000 miles, regular oil changed every 5,000 miles, no engine problems, almost no city driving involved. I will stick with the same treatment in my 8.

 

Aye...there have been a number of major sludge issues with BMW's spec'd intervals. Basically if you follow the 15k changes, you'll destroy your engine, even if you use bmw's own oil!!

I don't know how far along that particular class action lawsuit has gotten yet.

 

crossbow -

What oil do you like for:
a n/a RENESIS ?
a blown RENESIS ?

Looking for weight & brand.

 

but castrol doesn't make a real synthetic .....syntec is a group III

rotarygod as taught me well:-)

 

You give me too much credit! lol

Castrol does make a group IV PAO based synthetic. I'm just not sure if it is still available in the U.S. It may be. Oil companies are constantly changing their formulations so you never know what your oil may be at the next fillup. I remember several years ago when I used Havoline (my favorite conventional). I had one oil change where the oil was a darker amber color and at the next change the bottles were different and the oil was a lighter color. There was no mention anywhere of a change but it was obvious.

 

So is synthetic good or bad? I've heard both sides of the story. As long as I get free oil changes from my dealer every 5K I'll stick with the dino they give me.

 

I've been using synthetic in rotaries for years. I know many people that have.

 

I use dino juice and change every 2500 miles. Not a worry in my world

 

I thought the manual said something about SAE 5w20 non synthetic

 

My dealer said synthetic was fine too but i still think the manual said to use non synthetic, has anyone had any synthetic related problems, i haven't. I still switched to castrol gtx non synthetic SAE 5w20 cause

 

I actually don't know why?

 

As explained to me synthetic breaks down the seals, at least in older rotaries. I was told it is LESS of a problem in new rotaries but the problem is not necessarily solved since there isn't enough long-term data to know. To me that doesn't mean that it won't be a problem, just less of one or take longer to happen. I'm not sure that I would trust it knowing this.

 

The first formulations of group IV synthetic oils were found to cause some forms of rubber seals to swell. This didn't apply to all rubbers though and only affected some engines. Current group IV oils address this issue in one of two ways. The first way is to use an additive that cancels out this effect. Some are doing this. Technology has led to the advancement in the formulation of the group IV base oils themselves now that actually let them formulate this property into the base stock itself. The current group IV synthetic oils address this issue and no current oil should have any issues with any current technology engines. I've never had a single issue running a synthetic in rotaries and I'm using it in my '84 RX-7 right now. Have been for a very long time.

 

No matter how many times this is discussed, it is probably worth reiteration: Using synthetic oil may be worse, as good as, or better than conventional oil in the Renesis, but there can be no question that using synthetic oil is not expressly authorized by Mazda, and this creates a whole lot of wiggle room for Mazda to attempt to deny warranty claims in such cases.

Is it rational to take such a risk it if you under the 4 year/50k warranty?

I don't think so, but I won't pretend to think for anyone else.

 

I can't stand variable interval servicing, or extended.

However, at £80 per service for the RX8, I'll have it done at least twice in the recommended interval.

The Beetle is on long life - up to 20K between services and 2 years. So, I figure I want it done at 10K, but because I guess the long-life oil is going to be better, I stick with it.

I am charged £196 for it (the difference in costs between oils is not that much, btw). So I check my oil, and what is there? Lovely green long-life oil? Nope. Brown oil.

It wasn't brown BEFORE it was serviced.

Got it changed properly, but that experience makes me very reluctant to own a VW again (well, that and how crap the dealer is).

 

I know it's not worth the risk to me. Unless Mazda recommends differently I am going to stay away from synthetic.

 

...or at all for that matter. Is it rational to go around telling dealerships something that would be questionable that they can't prove anyways? I don't think so, but I won't pretend to actually use my brain or care about my engine for that matter.

 

There is absolutely no warranty wiggle room. Any 5w-20 oil that meets the quality designation SL or ILSAC keeps your warranty whether it is conventional or synthetic.

 

Try explaining that line of logic to Mazda, even when you have the dealership on your side, if/when Mazda denies a $2,500 warranty claim.

Life's all about tolerance of risk. If you feel comfortable taking the cost of a new rotary engine risk, regardless as to whether synthetic oil factually caused a mechanical failure, that's your perogative - you shouldn't talk to people as if they're ******** because they're not as willing.

I personally am deeply skeptical of the good faith of large corporations, and will act to protect my ASSets.