Synthetic or Conventional?

[james jefferson]

Originally Posted by joey

I have never used synthetic oil.
Is it really better than regular oil?
Any website links to an unbiased comparison between synthetic vs. regular oil?

yes, i am really sold on castrol syntec been using it for about 10 years now on my vehicles. even use it in my riding lawnmower and believe it or not on shaft of my vent fan in my roof of house. of course mobile one is excellent also, but i prefer syntec. try it you'll like it, but its about $4.75 a quart.

[joey]

Originally Posted by james jefferson

yes, i am really sold on castrol syntec been using it for about 10 years now on my vehicles. even use it in my riding lawnmower and believe it or not on shaft of my vent fan in my roof of house. of course mobile one is excellent also, but i prefer syntec. try it you'll like it, but its about $4.75 a quart.

How do I know if I will like it? We are talking like it is a favorite beer
We need a Consumer Reports or third party tester to perform a controlled test. I would pay the extra money without hesitation if I thought it was better for the car. Years ago I thought I read synthetic can also be bad for some cars. How do we know we aren't being duped by scare tactics and/or smooth marketeers?

[II kings 9:20]

Originally Posted by joey

How do I know if I will like it? We are talking like it is a favorite beer
We need a Consumer Reports or third party tester to perform a controlled test. I would pay the extra money without hesitation if I thought it was better for the car. Years ago I thought I read synthetic can also be bad for some cars. How do we know we aren't being duped by scare tactics and/or smooth marketeers?

IMHO consumer reports is an awful place for the kind of info you are looking for. I have found many errors and strong anti American bias in their "reporting". I use them as a fact and figure guide (recalls, NHTSA data, dimensions etc.). I would google for the unbiased info you are seeking and while we are on the topic your oil filter is as important a choice as your oil. I am a synthetic guy, My plan was for Mobil 1 but I got Amsoil for only $2.00 more per case of 12. In every measurable test except cost synthetic is better (4ball wear, shear strenght, cold pour, heat resistance et.al.). Most cars in virtually every major and minor race series use synthetic. 24 hrs of Le Mans and Daytona etc champions use synthetics. I know several people who use regulr oil for 200K+ with no oil burn.I think the theoritical and actual advantages of synthetics may not add that much in the real world because regular oil is so good and engines wear better with modern alloys. In a previous post i indicated to check the cold pour for yourself, that was enough to convince me and it does'nt matter if you live in a warm climate put a bottle of each in the freezer overnight. I did it in mid winter at 15 below, this alone tells me it is better for the engine. CR does provide useful facts and they commmissioned an independent study of NY taxi cabs (virtually all city driving) and using regular oil the changed the oil in one group at 3K and the other at 6K. At 100K engines were broken down and digitally analyzed and there was no difference in wear. This every 3K yang is the biggest dupe going started by Penzoil (owner of Jiffy Lube). I don't blame them, it's good for shareholders. Kendall Oil still around today has as it's symbol a hand with two fingers up. This was the first oil in the 40s that could go 2K b/t oil changes. Look how far we have come. We put a man on the moon yet our oil can only go another 1K miles b/t changes I believe in following recommended factory intervals. The X5 gets changed at 12-15K with Syntec specified by the factory. The Ferrari Enzo requires a special Shell synthetic at $60/qt and if you don't use it you void the engine warranty ( a $200K rebuild). There is no reason why you can't get 200K with regular oil and intervals, many others have done it on lesser cars. Think of it this way, Mobil 1 costs about $2.50 more /qt than even some cheap oils. Over 100K miles you would do 13 oil changes (7500 intervals) at 7qts each. 13x7x.$2.50=$233.27. It's your call, go with what you are comfortable with but clearly cost is not an issue. The 300C owners manual states synthetics are fine so safety is also not an issue. I now struggle with which filter to use but I made a decision to go with Amsoil's larger than stock SDF 15.

[joey]

It would be nice if the car manufacturer would qualify/recommend a synthetic oil alternative replacement.
I just don't feel qualified to pick a synthetic oil.
I did a Google search and happened to find part of the Consumer Report taxi test you mentioned. In that article they say

But there is little indication that the brand or weight needs to be given serious consideration, and synthetic oil has no discernible advantage over the old stand-bys.
http://www.triumphspitfire.com/Oiltest.html

But then there was this said in another link.
The synthetics offer the only truly significant differences, due to their
superior high temperature oxidation resistance, high film strength, very
low tendency to form deposits, stable viscosity base, and low temperature
flow characteristics. Synthetics are superior lubricants compared to
traditional petroleum oils. You will have to decide if their high cost is
justified in your application.
http://www.unofficialbmw.com/all/misc/all_oilfaq.html

I am just as confused as before and frozen into inaction

Don't know if this is of help or interest, but I had saved this link awhile back regarding oil filters.
http://minimopar.knizefamily.net/oilfilters.html

[II kings 9:20]

Thanks, I have visited that oil filter site many times, one thing is as sure as the sun rises in the east, I will never put a Fram filter on any car of mine. I tend to follow the second opinion that synthetics are superior at least in tests, who knows in the real world. Maybe your engine could go 450K instead of 250K? Most of us will have gotten rid of it long before we would ever appreciate the advantages. (although I have seen some cars burn oil at 70k, abuse??)

[joey]

That reminds me of my Super 90 Audi I owned about 25 years ago.
After about 70k miles it was burning a quart a day.
A case of failing valve guides.
I had to leave 5 minutes early every morning for work to add a quart of oil.
I drove around with a case of oil in the trunk.
Couldn't believe it when I traded into to a dealer for $500 (on a rainy night 15 minutes before closing time).
Luckily the car was painted black or they would have seen the oil smeared
all down the sides of the car.
Try to clean the car and the rag would stick to the paint

Found a picture. Man, that was one ugly car! Much better in black.

[Abshear7]

FYI, I mentioned the change to synthetic to my dealer on Friday and was advised not to do it; service mgr. stated that the MDS system may or may not be affected differently by a different type of oil, so safer to stay with mfr. recommended. Not sure how valid of a concern this is, but thought I'd pass it along.

[II kings 9:20]

Originally Posted by Abshear7

FYI, I mentioned the change to synthetic to my dealer on Friday and was advised not to do it; service mgr. stated that the MDS system may or may not be affected differently by a different type of oil, so safer to stay with mfr. recommended. Not sure how valid of a concern this is, but thought I'd pass it along.

Good point, being too much of a do gooder enthusiast trying to do all this stuff for longevity and wind up ruining your engine. You never see the missile that kills you and this could be one of those missiles except that the owner's manual clearly states that it is ok to use synthetic (though not specifically recommended nor is conventional oil specifically recommended either). It does recommend API grade and weight but no brand or type is specified. All Mercedes (including the Euro V12 which pioneered the MDS) use synthetic. Frankly, I am suprised that DC does'nt require only synthetic because of significant sludge reduction vis a vis the MDS. Since they say either is OK, they probably found in thier 6.5 million miles of testing it does'nt really matter.

[II kings 9:20]

Originally Posted by joey

That reminds me of my Super 90 Audi I owned about 25 years ago.
After about 70k miles it was burning a quart a day.
A case of failing valve guides.
I had to leave 5 minutes early every morning for work to add a quart of oil.
I drove around with a case of oil in the trunk.
Couldn't believe it when I traded into to a dealer for $500 (on a rainy night 15 minutes before closing time).
Luckily the car was painted black or they would have seen the oil smeared
all down the sides of the car.
Try to clean the car and the rag would stick to the paint

Found a picture. Man, that was one ugly car! Much better in black.

You should be ashamed, that Audi is beautiful, it reminds me of my old Peugeot.

[james jefferson]

i notice on page 294 of owners manual it says that synthetic oil maybe used if quality specifications are met (and they are by mobile 1 and syntec). i changed my oil at dealer to syntec at 300 miles and again at 989miles. now i'm on the regular 3k to 4k intervals. As golly gee whiz info, i used 30w syntec in my sears riding lawn mower for last 4 years of its life. when about 13 years old, and somewhat beatup i lost all the oil by some gasket that went. interestingly, i cut grass for about 30 minutes before i noticed oil streaks in my grass. no oil and it was humming along, i didn't know it. my son in law changed gasket, and mower still hums along. And no i do not have any financial connection to castrol. lol.