who here uses synthetic oil?

[Douglas]

did you wait to rebuild your motor first? i'm interested in hearing what people are using & whether they've noticed any differences.

[Mark in KS]

From everything I've heard for the past 6 months, it's best to use non-synthetic motor oil.  That's because the seals will leak due to the great penetrating and viscus (sp) properties of the new synthetics.  I changed the oil on the 113 I just purchased and used good ole Valvoline.  So far, no leaking seals.

[Cees Klumper]

Most opinions favor synthetic oil after an engine rebuild, when the seals will have been replaced. Many have reported very good results when using synthetic oil from new/rebuild. Should you want to start using it in an engine before a rebuild, then you will have to watch for leaks, as well as changing the oil a couple of times in a short time, because the synthetics tend to loosen deposits/sludge from the interior of the engine which may then clog op oil passages etc. One tip to determine whether you can safely switch from conventional to synthetic oil without a rebuild, is to check the inside of the valve cover - if there is more than a minimal amount of sludge , it is probably better to stick to conventional oil.

Cees

white 1969 280 SL

[George Davis]

I agree completely with Cees.  My engine was rebuilt less than 100 miles before I bought the car, and after break-in I switched to synthetic oil.  On higher milage engines, I stick to conventional oil, just use a good name brand.  Personally, I consider the break point to be around 20,000 miles: under that, I'd probably switch to synthetic; over that, I'd stick to conventional.

George Davis
'69 280 SL Euro manual

[Douglas]

"The most asked question about engine oil for vintage cars is compatability with the new synthetic grades. A fully synthetic oil, or a mineral/synthetic blend, can be used in any engine. The early synthetics that were introduced approximately 15 years ago had a slightly different swell rate for rubber seals and began to be known for creating leaks in an engine that had the seals swelled to mineral oil. But that problem has long been corrected, and swell rates are nearly the same for mineral and synthetic oils. In fact, many old car owners prefer the better protection that synthetic oil provides, especially during cold start-ups and in extreme heat. While synthetic usually costs between 3 and 4 times what conventional oil does, the running costs are equal as synthetic doesn't have to be changed as often."

Ray Bohacz, Hemmings Motor News, Jan/Feb '03, p.61.



I was so impressed by this article that I decided to try Mobil 1 in my M110-equipped W114 sedan. The results have been excellent -- no leaks so far and on an original motor with 100K on it, i actually got 20MPG on a 80+ MPH sprint up the east coast from NY to Boston and back. i was astounded.

[George Davis]

Douglas, thanks for posting that info from Hemmings, I think you've changed my mind about using synthetics in high-milage engines!

George Davis
'69 280 SL Euro manual

[Douglas]

george,

glad you enjoyed that. i wasn't really trying to convince anyone; just trying to get some personal experiences for comparison.

the hemmings article seemed pretty positive though & my experience with my sedan is making me lean towards synthetics in the M130.

by the way, sounds like we have very similar machines. have you considered posting pix in the photo gallery? i'd like to see your pagoda.

[George Davis]

Douglas,

I understand about not trying to convince anyone, but still appreciate that info, it was new to me.

I'd like to post a pic one of these day, when I'm more digitally enabled.  But truth be told, mine is no show car, just a decent driver that could use some cosmetic work.  One of these days, though.  Your car, on the other hand, looks fabulous!

George Davis
'69 280 SL Euro manual

[Douglas]

george,

thanks for the kind words. like many people on this site, i have a curiosity about seeing other people's pagodas that borders on the obsessive. please do share pix with everyone when you get a chance. we are all curious!

in the meantime, i would like to change the subject to oil consumption -- how much are people burning, if at all? and what kind of oil are you using?

[JPMOSE]

I wanted to comment that I put Amsoil synthetic 10W-40 in my engine with 133K miles (always conventional oil prior) and have only consumed 1/3 quart in 700 miles.  I also have all original seals with the exception of the valve cover gasket.  I have always been a strong supporter of synthetic oil and will continue to be!

I also serviced my automatic transmission with Redline D4 synthetic fluid (changed filter as well).  I didn't notice any difference in shifting (still shifts with a punch from 2nd to 3rd).  but I haven't check vacuum pressure at the modulator yet.

Best Regards,

J. P. Mose
1968 250SL

[mdsalemi]

Interesting revival of an old topic.

Recently our local MBCA section held its tech session at Roush Aviation, part of Rousch Engineering, yeah that's Jack Roush he with the winning NASCAR teams.  Aviation is also his passion and he owns and flies two WWII P51 Mustangs.

The Aviation rebuild facility in Livonia, Michigan rebuilds and restores Rolls-Royce and Packard Merlin V12 engines (from the Supermarine Spitfire and P51) and has even developed some new parts for it including roller cams and ceramic coated pistons.  No mean feat when you have to get these parts certified for airworthiness.

The only oil they use?  Mobil 1.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[Benz Dr.]

I've been using synthetics since 1982 which is probably longer than almost that is using it now. Back then there was a lot of resistance to this type of oil but not so much these days. When you consider how much used oil is floating around it makes good sense to use something that can stay in your engine for a whole year.

I have a combine that we bought new in 1982. It has a Perkins diesel in it and has about 2,800 hours of use ( this is about 150,000 miles ) . I can still see the part numbes on the valve springs, it's that clean inside the engine. I change oil every 400 - 500 hours with AMS/OIL 15 W 40. Normal change intervalls would be 100 hours and 23 liters of oil.

Ask me to show you our combine during the summer party.

Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org
  1 877 661 6061

[France]

Hi guys,

I had the same experience as several here--started using Mobil 1 when I acquired Carling at about 100K miles.  Four years later I am getting aboutg 20MPG and using reasonable amounts of oil for an old car.  I don't baby this car--she is a daily driver and remains stationary for long periods of time.


Trice
1968 280SL US, signal red/bl leather, auto, kinder
Sarasota FL; Alsace France
There's two theories to arguin' with a woman.  Neither one works.

[enochbell]

I recently read an article on recommended oil change frequency for synthetics, and the science of the argument holds that synthetics actually get better in protecting moving parts as they get used (up to a point); the article said the composition of the subparticles in the oil made it more slippery after 5k than it is poured out of the bottle.  The article was arguing against frequent oil changes, from an economic, environmental and performance perspective.

Now, that said, I still change my synthetic every 6 months or 5k miles in all our family cars,   The real question is...does age have any bearing on the life or effectiveness of synthetics as it does with organic products?  Can I go to a yearly change on my W113, which gets driven no more than 2k per year?  

Thanks,
g

'64 230sl, fully sorted out...ooops, spoke too soon

[France]

My engineer better half cites the same economic/environmental/performance arguments you've mentioned, so we change Carling's oil every 8 mos. to a year, after she's driven 2,000 to 3,000 miles.  She was just given another bill of perfect health--I drove her for 9 weeks this spring.

Trice
1968 280SL US, signal red/bl leather, auto, kinder
Sarasota FL; Alsace France
If you're not the lead dog, the view never changes.

[rwmastel]

quote:Originally posted by France

--she is a daily driver and remains stationary for long periods of time.

Trice,
You might have to explain this one for me!  

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[J. Huber]

I guess I am the odd-man out (what's new) I still use good ol' Castro GTX 10W-30. I change the oil & filter every season -- averaging about 2000-2500 miles between. This is all in a replacement block that now has maybe 65K miles on it. Cylinder head & valves far less (18?). Would I stand to gain much from switching? Any down side to synthetics?

James
63 230SL

[Chad]

quote:Originally posted by Douglas
[br
I was so impressed by this article that I decided to try Mobil 1 in my M110-equipped W114 sedan. The results have been excellent -- no leaks so far and on an original motor with 100K on it, i actually got 20MPG on a 80+ MPH sprint up the east coast from NY to Boston and back. i was astounded.

20mpg sounds like great mileage for a w114. Is it the 4-cylinder or six-cylinder?

I ask because my M130 six-cylinder w114 coupe 250C get about 15-16mpg in town/highway, doesn't matter. It is a 2.8L engine.

1967 230SL (Manual)
2006 Prius (Mostly Electrical)

[Douglas]

Chad,

I've got the M110 6-cylinder -- the twin-cam -- in my W114 sedan. Yes, 20PMG is astounding mileage. (The city mileage is another story, of course...)

Douglas Kim
New York
USA

[France]

Sorry, Rodd, for the shorthand...

I meant to say that although she is a daily driver "when I'm there," she can remain in storage for weeks at a time.  Then she's driven daily for a couple of months, after which she's put up for a couple of months.  It hasn't seemed to bother her at all.  Mind you, I'm careful of how I store her (65% humidity, battery disconnected, tires plumped to 35 lbs,etc.).  I don't like to leave her, but I must, and it's nice to know that you can if you take precautions.  I've found the trick to startup is to normalise the oil pressure before turnover--makes all the difference.

Trice
1968 280SL US, signal red/bl leather, auto, kinder
Sarasota FL; Alsace France
If you're not the lead dog, the view never changes.

[Raymond]

There is no downside to engine health from using synthetic.  

In the Star magazine last year an engineer went into depth on the benefits of synthetic oil and explained why MB now specifies synthetic for all the production engines they have ever built.  That includes all the old, used engines running around.  

Even the old airplanes that I fly, which are still running leaded fuel, benefit from synthetic oil.  The airplane I sold last year had over 3,500 hours on the cylinders and compression was within 3 lbs of factory spec on all four cylinders.  

A former employee had 50,000 miles on an Acura that he raced on road courses for two full seasons and when he tore it down it looked like brand new.  

All endurance race cars and motorcylces use synthetic oil for good reasons, including the fact that you can see performance improvement on a dynomometer simply by abandoning the dinosaur oil for synth.

If you aren't using synthetic in your Pagoda you're depriving her.

Ray
'68 280SL 4-spd Coupe

[J. Huber]

Well, shucks. Thanks Ray -- I wouldn't want to deprive the Guzzi. So next change will be synthetic. Next question -- what's the synthetic oil of choice? comparable to a 10-30.

James
63 230SL

[mulrik]

OK let's get some science into this (I'm a scientist by profession...). If you read some of the links below you'll see that engine oil is classified into an API category.

I've also included some links to additives explained and some of the test parameters used to classify the oil into the above mentioned categories. I don't know if synthetics are better in our engines than mineral oils or if one should use 0W, 5W, 10W or 15W-40 oil in our engines. But read below at become more knowledgeable.

As Joe Alexander has previously written all oils today are much better than at the time our cars were made. Castrol makes an oil which they call classic oil and sell in a nice tincan, and claim is made especially for classic cars; DON'T go near it!!! It is classified SE which is way below todays standard of SL/SM. So look at the API classification when you buy you're oil.


http://api-ep.api.org/filelibrary/API_MotorOilGuide_2004.pdf
http://www.performancemotoroil.com/info_about_motor_oil.html
http://www.performancemotoroil.com/Mobil_1_test.html
http://www.infineum.com/information/api-passenger-sj-sl-2004.html

Enjoy
Ulrik


'67 250 SL Papyrus White 113043-10-000023

[Bob G ✝︎]

I would not recommend synthic oil in an older engine. I tried it and because it is so slipery it worked it self pass the seals and on to the floor . I changed back to Castrol 20/50 no problems.
however if you rebuild your motor there may be some newer gaskets including  the rope gasket that have improved protection. Until then I would not attempt using it in my 1968 280SL.
this does not mean I do not beleive in the product. I use mobile one 10/30 in my wife's 1992 300-E and Red line oil in my 1987 ford mustang.


Bob Geco