Engine oil type

[Spangy]

Hi,
I want to change the oil in my 1968, 280SL and have a question regarding the oil type to use.  My experience with flat tappet valve trains in other autos is to use a zinc additive, or racing oil.  Does this hold true for the merc?  Do I use a 10w40?  What do you folks think about dino vs synthetic?  Any help will be appreciated. Thank you, Dale

[Benz Dr.]

I use 10 W 40 synthetics or regular 15 W 40.  I also use a zinc additive like Comp Cams or similar.

[Jkalplus1]

This is useful info, thanks.  If it is good enough for Benz Dr, it will be good enough for me!  I read a lot about zinc additives, but I am not sure which one to get.  The sales brochures and marleting ploys baffle me and smell of BS.  I was planning on buying this:

http://www.ebay.ca/itm/COMP-CAMS-ENGINE-BREAK-IN-OIL-ADDITIVE-12-PACK-159-12-/200764629082?pt=Motors_Car_Truck_Parts_Accessories&hash=item2ebe81205a

Is this the one you are talking about?

Tks,
J

[Spangy]

Great info!  Thank you very much for the info.  I will go with a 10w40 and most likely go with the comp cams additive too. 
Thanks again,
Dale

[jeblack123]

I received this advertisement from Hemmings about an oil with higher levels of zinc and phosphorous designed for classc cars in an e-mail today. Any thoughts as to its usefulness?

http://blog.hemmings.com/index.php/2012/09/21/hemmings-introduces-zinc-rich-motor-oil-formulated-specifically-for-classic-cars/?refer=news

Thanks,

James

[mdsalemi]

Just got the same note today.  Looks good.  I wonder who makes it for them?  Seems to have that magic number for the zinc and phosphorus.

Funny if you drill down on the product intro, and read the comments..."no need for this stuff"..."snake oil"..."too pricey"...

Let no good deed go unpunished.

[mdsalemi]

See the other thread titled "Oil with Zinc and Phosphorus."

[Tomnistuff]

Metric Motors, in the crate with their rebuilt engines, sends the following sheet.  If it`s good enough for Mike and his crew, it`s good enough for me.  By the way, Castrol invented ZDDP (zinc dialkyl dithio phosphate).
Tom Kizer

[mdsalemi]

Castrol themselves, however, recommends their Edge 5W-50 formulation, which replaced Syntec 20W-50.  In the UK, they seem to offer a more comprehensive line under the Castrol Classic banner...

Who knows what or whom to believe?

[mdsalemi]

I ended up buying 6 quarts of the recommended [by Mobil 1] motor oil, their 15W-50 today.

They seem to change formulations every now and then.  This one is recommended for older engines.

Nominal zinc level 1300 ppm, phosphorus 1200 ppm.  This is the highest levels by far in the Mobil1 line, EXCEPT for their racing oil formulations. I woud imagine these are a bit harder to find.  They contain 1750 and 1850 ppm respectively; are available in 0W30 and 0W50, and are not recommended for street use.

[zoegrlh]

I have been using the Castrol GTX High Mileage 10W40 oil for over 10 years now.  It is a "part synthetic" which means it is a synthetic blend oil for API service SN, SM, SL, SJ.  Seems to work for me.
Bob

[Benz Dr.]

Look at API the rating on the bottle. The one you should look for is '' SM '' which contains moly additives. This is the replacement for zinc used in modern engines. If you can't find anything else this should be your second best choice.

  Phosphorus is part of the detergent package if I remember corrrectly. 

[Paul & Dolly]

 
I suspect that most of us do less than 3000 miles a year, so an annual oil (of correct specification) and filter change will prove more beneficial than using the higher priced Synthetics and Long life oils.

Synthetics are fantastic for modern high efficiency engines especially where turbo or supercharging is involved, and extended service intervals have been introduced - but our engines were designed for frequent  regular oil changes - i.e. nice clean oil.

Whilst mechanical shearing will have little effect on a modern synthetic, Combustion product contamination will affect any oil or additive package, so please do not concider that by using a "modern" oil , that we should skip the regular and frequent oil and filter changes .

Paul

[zoegrlh]

Here in the states, EPA, in 1996 forced ZDDP (Zinc Dialkyl Dithio Phosphate) from domestic motor oil.  If your engine was designed prior to 1989, your cam and flat lifters required ZDDP in your motor oil to avoid premature deterioration.  If you are one of those drivers that require assurance towards wear of your enging parts, you can find this product ZDDP Oil Additive at Eastwood.com.
Bob