Should I go synthetic?

[Gribbin]

I have a 83 911SC with 122k. It is due for a oil change and was wondering if I should go with synthetic oil. The car runs well and does not leak. What is the difference? What brand is a good brand?
Any help would be great!

Thanks, John

[tarix]

In general all fully synthetic brands are "good brands". The main differences are in the additive package they use. Porsche is currently partnered with Mobile 1 and so in some ways that might be considered the "best brand" because it comes recommended by Porsche.

Synthetics generally offer better protection, better heat dissipation, and better operating range.

If your car isn't a daily driver and you don't take it to events then its mostly a personal choice. The people who will see the most benefits are heavy drivers.

There is a ton of information available about synthetics and plenty of oil discussions have appeared on this board. Start with the synthetic FAQ here on Pelican and if you still want more information use the search button above!

http://www.pelicanparts.com/techarticles/mult_gas_and_oil/mult_synthetic_faq.htm

[island911]

almost too much info here.

I run Synthetic; and agree that it generally offer better protection, and better operating range. . . .but better heat dissipation? I dont think so. There is a dino or two, which have a fairly high zinc content. I think syth would have a hard time competing w/ those in the heat dissipation race.

[tarix]

Originally posted by island911
better heat dissipation? I dont think so.

Yup, you're right. I apparently pulled that out of my tail pipe. Should have checked first. I was under the impression that it had better theromdynamic characteristics, but I can't find any mention of that anywhere.

Also, if you aren't overloaded yet, Mobil has an entire site dedicated to Mobile 1. http://www.mobil1.com/

[donstevens]

Do it.....You'll love it.

Don

[Gribbin]

dO YOU CHANGE OIL EVERY 3K? wHAT ARE THE RULES?

[Jim Sims]

Be prepared for engine oil leaks if you move to synthetic. Jim

[gr8fl4porsche]

No - too risky. Very good chance your dry motor will start to leave little tears on the garage floor.
Nothing wrong with Dino oil - just change it regularly.

[David]

No, unless you want more oil leaks.

[Carl83911]

GO FOR IT. how is your compression? leak down results?

If you have good compression and great leak down test results, go for it. you should be ok.

[chuckr]

I put Synthetic in my 83SC @ 160,000 miles. I was using
Valvoline VR-1 20/50 and had NO leaks. I went with Redline
20/50 and had NO leaks ! I did notice my engine ran cooler
and I got better milage.

[JackT]

This gets debated over and over and over again. There have been tests and tests and tests and there is never a clear reason to switch to synthetic, except that you can go more miles before an oil change. I change my oil about every 1500 miles so that is not a reason for me. In my simple mind, if my car didnt leak with Mobil 1, which it does, I would use it becauase it can't hurt anything. In fact, maybe, when the weather is cold, on startup, it provides better protection. Otherwise, the dino oils listed above will do just fine. There are a lot of other things that will go wrong with a 911SC engine before it is damaged because of using Castrol GTX instead of Mobil 1.

[Por_sha911]

The silicone ones are firm but just don't look real. I say stick with natural... Oh, wait, this isn't the OT forum. Sorry.

[donstevens]

Originally posted by Gribbin
dO YOU CHANGE OIL EVERY 3K? wHAT ARE THE RULES?

Synthetic oil almost always has the ability to go twice as far, often 3 times as far as conventional oil between changes. Every car is different so there are no steadfast rules to go by. Used oil analysis (www.oaitesting.com) is the right tool to use to determine how far you can go on the oil (any oil for that matter)

If you do a little studying you'll find that 3000 mile drain intervals are a farce, even with conventional oils. https://www.amsoil.com/usa.aspx

Don
www.lubedealer.com/dstevens

[livi]

I was just thinking..

The drain interval debate usually circles around the quality and brand of oil. Some people argue that synthetic oil keep its properties longer than dino oil and because of that can be used with longer intervals.

But what about all the small metal parts and dirt that is suspended in the oil posing a threat to the internal engine parts ? Would the accumulation of such debris not be the same with any kind of oil and hence make an important factor for drain intervals ?

Please correct a newbie as you gents see fit !

[anthony]

Originally posted by livi

But what about all the small metal parts and dirt that is suspended in the oil posing a threat to the internal engine parts ? Would the accumulation of such debris not be the same with any kind of oil and hence make an important factor for drain intervals ?

Don't you think any metal bits or any debris would be caught by the oil filter?

[livi]

Yes if they are big enough, but I figure there are debris in all sizes and a lot of it so small it passes threw the filter.

Well, it was just a thought...

[Hayabusa]

What about on a fresh rebuild? Will the same "drip" rule apply to the older type engines with brand new seals and tolerances when/if switching to the synthetics?

[Sonic dB]

Dont mess with a good thing...stick to dino and avoid oil leaks

[Hayabusa]

Thanks. It does sound like an easier solution.

I was a quart low the other day out with the 930 and I went in to the auto store, picked up a quart of Castrol. I felt like I was cheating a bit since I run it in my other cars/motorcycle.

A full synth oil change compared to dino would be marginally noticeable.