Oil for 1969 MBZ 280SL

[DavidHunter]

 Am going through information overload. My recently acquired 280SL needs a top up in oil.
The service garage, a very reputable MBZ SL specialist recommends any non-synthetic oil.
The garage that sold me the car recommends 10/40 semi synthetic oil.
I have read through the forum and the recommendation are as varied as pebbles on the sea shore.
Has any one got any suggestions other than write a load of Post-It Notes, close your eyes and pick one?
Any help would be appreciated.
David

[WRe]

Hi,
my 2 cents to this point: Old motors need "old" oil means on mineral basis, no synthetic or semi-synthetic oil because this is to agressive. I'am using and this is also the recommendation of MB's Classic Center 15W40 but 20W50 would also be good. There are a lot of producers of these oils. See also MB 228.3 and 229.1 : https://bevo.mercedes-benz.com/bevolisten/bevo-sheets-sort1.html.
If your motor was totally refurbished/rebuild it could be appropriate to use semi-synthetic oil.
...WRe

[GGR]

Regarding oil, you risk to get as many opinions as posters. So your post-it strategy may not be a bad one in the end.

I would also recommend non-synthetic 15W40 for winter/colder climates and 20W50 for summer/warmer climates. You need to get an oil with sufficient zinc in it as otherwise you may end up with a damaged camshaft. Zinc was progressively reduced in oils to conform with emission regulations, but our older engines need it. Regulations are different in various parts of the world so you should see with a local vintage car club what they recommend. UK based members may also get you the right information. 

[Bonnyboy]

Having followed oil threads intently on various forums I always find this topic interesting.  I admit I never took OIL 101 at university and don't even understand why oil works the way it does. 

Every spring I buy myself 5 gallons of Shell Rotella T, 15-40 and put that in every old toy I own.  MGB, Triumph and Honda motorcycles and of course my 280sl.  Its seems to be the oil of choice for many gearheads as it has a high zinc level designed for diesel engines.

I change oil in everything every spring and so far have been happy with the results.

[Jkalplus1]

I use 10w40/full synthetic with zinc additives on my rebuilt engine: no problems, zero consumption between oil changes. That said, for having been there myself when I bought my car a few years ago, I can completely relate to how you feel. In the end, given how much care we give our cars, and the thorough frequency at which we change our oil, any of the advice given above will work perfectly, as the suggestions given all specify oil that is compatible with the specific requirements of our engines.  More fluid modern 0wxx or 5wxx grade oils might lack the film thickness required or zinc content. Stick to the advice, frequent changes, resist over-revving the engine until it is warm and you and your camshaft will remain best pals!

[jameshoward]

I think that unless you plan to leave your car out in the depths of winter or start it when it is very cold, you might consider the viscosity issue of less relevance. I do. The specs were written when the car was built, so it would have been expected that the cars would have been used in all weathers. Not the case today.

Regular oil changes are quite important, I think. Most folk seem to change oil every year as a minimum. I do, and I do few miles. It makes little sense to me to put a very expensive synthetic oil in my car for that reason. Another reason I don't use synthetics is because the one time I tried it I sprung a few leaks. I have now settled on Halfords classic car oil. It's a 20-50 designed - so they say - specifically for older cars. I can't fault it.

[franjo_66]

I concur with the frequent oil change strategy.
Every 6 months for me irrespective of mileage.

Have been using Mobil 1 15w50 with no issues. It has the high levels of zinc needed for our engines.
No leaks, no consumption, etc. (Original engine with documented 67,000 miles)

[jf308]

My mechanic here recommended Shell Rotella T, 15-40 as it has a high zinc level. Apparently his concern is the flattening of the cam lobes with reduced zinc content in newer oil formulations.
I found it at O'Reilly's Auto Parts in a bulk container.

[GGR]

Here is an interesting discussion: http://speedtalk.com/forum/viewtopic.php?f=1&t=35836

The first poster comes out with tests and Rotella T comes out OK. Then the discussion goes that there are a lot of failures if not using additives. Brad Penn seems appreciated though I read elsewhere that ZDDP contents were not as high as claimed. I also read that mixing additives was not a good idea because one doesn't know how it is going to alter the original oil formula. Also, too much ZDDP causes wear on the long run.

I use Brad Penn 20w50 when I do oil changes, and Rotella T 15w40 when I need to top up away from home. The day I read Brad Penn was not up to its claimed zinc level I freaked out and added some left over ZDDP additive I had. So far so good, no camshaft damage, but I really don't know for sure what's the best solution.

I'm afraid we're again in one of these threads about oil!

[DavidHunter]

Thank you all for your comments - think I am going to need more Post-It Notes to enable a random choice to be made.

This is a really stupid question but I cannot see in the 280SL Manual any details as to where you top up the engine oil.

I can check the oil level with the visible dip stick but there is no mention of the "this is where you put the oil" hole.

Anyone got a photo or diagram that might help?

David

[jf308]

Top of engine.  Forward portion toward front of car/radiator.  Oil Fill cap.  Don't think you can miss it.

[thelews]

Brad-Penn Green Racing Oil, the best, use viscosity you feel appropriate for your engine.

[dseretakis]

Brad Penn 20W50 green racing is what I use. My gf's family lives near Bradford PA where the refinery is located. Whenever I visit, I buy several cases for myself and friends.