Engine oil brand and type

[mauro12]

Hello guys , I’ve recently replaced the engine oil and as usual I’ve used the bardahl xtc 15w50.
I was reading some article regarding the use of royal purple . Is worldwide known to be probably the best , unfortunately is quite expensive in Italy , around 25€ per liter .I would like to know your opinion and experience and also what type of royal purple you use.
Thank you

[rwmastel]

We have hundreds of active members here, and each one probably has a unique personal favorite oil brand, oil weight, oil blend, etc....   I recommend you use the search feature to find past threads discussing oil just to see the wide variety of recommendations.  There is no agreement or general consensus on any of it.  Just use good oil, good filters, and replace them often.

[Benz Dr.]

Use 15 W 40. Brand isn't so important but it will have the viscosity and additives that you need.

[MikeSimon]

What I am watching for in all my engines that have "flat tappets", i.e.: no roller lifters in contact with the cam, is zinc dialkyl dithiophosphates, abbreviated ZDDP. Most oils of 10W40/50, 20W40/50 have a level of 1200+ ppm of ZDDP which you would want. Another decision factor is synthetic over dino oil to prevent sludge. But a lot of it is personal opinion and preference. That's why posts like this on most motor-related forums turn into the dreaded "oil thread"

[Mike Hughes]

15W40 from many brands is commonly used in Diesel engines and may have the higher concentration of the ZDDP we are seeking.  One has to be careful to check even 10W40/50 and 20W40/50 oils for adequate ZDDP concentrations these days, as many brands have reduced ZDDP concentrations recently, including Castrol.  However, it is worth noting that Castrol "Classic" 20W50 has a higher concentration of ZDDP than the Castrol 20W50 that is not marked "Classic."  In our area most auto parts stores only stock the regular Castrol 20W50, but I have been able to find the Castrol "Classic" 20W50 at Walmart.

[su8pack1]

I've been using Quaker State 10W-40 since I bought mine in 1982. Now that's getting hard to find,

[franjo_66]

Not to infer that this is the best oil etc, but the Mobil 10W-60 has zddp of 1300ppm, which is why I use it in my 230Sl. Also it is relatively easy to buy and not overly expensive for a synthetic, high quality oil

[Jordan]

Thought I would throw this out there to make it even more confusing. 

https://www.motortrend.com/how-to/diesel-oil-in-gasoline-engine/

[mdsalemi]

Updated May 2022:

https://www.mobil.com/lubricants/-/media/project/wep/mobil/mobil-row-us-1/pdf/mobil-1-engine-oils-product-guide-sheet--may-2022.pdf

Many don’t like Mobil1 for one reason or another but it’s sure nice to have a comprehensive list of product formulations with the zinc and phosphorus levels front and center.

I’ve been using whatever their current “street” oil (as opposed to racing, motorcycle, diesel) is with the highest levels of zinc and phosphorus is. For many years now it’s been their 15W-50. It’s a bit harder to find, but pre-pandemic I was finding it at Walmart of all places in 5 quart jugs. Last year had two cases of 6 x 1 quart delivered on sale from NAPA. Seek and you will find.

This is probably a list for North America only.

[Jowe]

Just throwing in another option. I use Valvoline VR1 Racing 20W-50, which is common available in Europe, at least. https://www.valvolineglobal.com/en/vr1-racing-oil/

[mauro12]

I was wondering if it is convenient to have the car serviced in the official Mercedes dealer . We have a club in my region and the dealer is our sponsor . Probably we will have the opportunity to have some good deal for regular maintenance.
I don’t think that back in the 60s Mercedes used their own Mercedes brand oil like today .

[rwmastel]

I would seriously question the ability of technicians trained only on the latest technology to do proper maintenance on a 50-60 year old car.  Even if you have a 55 year old service tech (rare, I would assume?), he/she has probably never worked on a car this age at the facility.  For example, will they know to be careful to not put a second seal ring in the top of oil filter canister?  It can be difficult to notice one is already in there, and having two can crack the canister.  I recommend using someone experienced with these older cars.

[mdsalemi]

I was wondering if it is convenient to have the car serviced in the official Mercedes dealer . We have a club in my region and the dealer is our sponsor . Probably we will have the opportunity to have some good deal for regular maintenance.
I don’t think that back in the 60s Mercedes used their own Mercedes brand oil like today .

I would say NO.

[thelews]

Shell Rotella T4 15W40 Diesel.  Been using successive versions, T2, T3, T4 for 15 years, no issues.  Higher ZDDP (enough) plenty of protection, approved for vehicles even though the rating is off the bottle.  I called Shell to verify.  Relatively inexpensive too.  https://rotella.shell.com/en_us/products/triple-protection-motor-oil/rotella-triple-protection.html

[franjo_66]

Updated May 2022:

https://www.mobil.com/lubricants/-/media/project/wep/mobil/mobil-row-us-1/pdf/mobil-1-engine-oils-product-guide-sheet--may-2022.pdf

Many don’t like Mobil1 for one reason or another but it’s sure nice to have a comprehensive list of product formulations with the zinc and phosphorus levels front and center.

I’ve been using whatever their current “street” oil (as opposed to racing, motorcycle, diesel) is with the highest levels of zinc and phosphorus is. For many years now it’s been their 15W-50. It’s a bit harder to find, but pre-pandemic I was finding it at Walmart of all places in 5 quart jugs. Last year had two cases of 6 x 1 quart delivered on sale from NAPA. Seek and you will find.

This is probably a list for North America only.

Thanks for that link Michael - very useful.
I noticed that the 10W-60 is not on there, (I suspect it's not available in the USA), but if anyone is interested, Ph level is 1300ppm and zinc 1400ppm. 
It is also a full synthetic oil

[mdsalemi]

Thanks for that link Michael - very useful.
I noticed that the 10W-60 is not on there, (I suspect it's not available in the USA), but if anyone is interested, Ph level is 1300ppm and zinc 1400ppm. 
It is also a full synthetic oil

All Mobil1 is full synthetic in North America. No hybrid or blends. And yes 10W-60 is not in their North American offerings.

[mauro12]

I’ve always used Bardahl and still I’m wondering why is not popular anymore in USA . Regarding the Mercedes dealers , unfortunately all mechanics that used to work on these cars are all passed away .
Who was 30 in the 60s now is very old or dead .

[rwmastel]

I’ve always used Bardahl and still I’m wondering why is not popular anymore in USA.

I'm not familiar with it at all.  Don't think I've heard of it.  I looked them up and it's available at Walmart and they do have a factory near Seattle, WA.  Maybe it is just simple lack of advertising and marketing?  They also sell 'stop leak' and 'no smoke' and other additives.

[mdsalemi]

Bardahl has made (for the USA) mostly additives over the years. They have a full complement of motor oils in their product line, and presumably available in the USA, but try finding them. I could not.

As Rodd suggests it's a matter of marketing and advertising. Castrol, Mobil, Valvoline and others are very large corporations with large marketing budgets. Breaking into the somewhat mundane business of motor oil is a tough sell for smaller companies. I think today that fewer and fewer people are changing their own oil compared to say, the 1960s and 1970s. Thus serving the rapid oil change franchises and commercial operations in large drums (30 Gallon and up) is most important. That's a guess, but I suspect its true.

Liqui-Moly is a German brand that has been trying to make inroads in the USA for a few years now, advertising in the car club publications. They advertise themselves as suitable for all the German cars (Audi, MB, Porsche, VW etc.) but if you open the hood of many modern Mercedes there is (or was at least) a sticker saying something to the effect of "We recommend Mobil1". I asked the LiquiMoly marketing folks about that and they said, "yes, we know about that. We cannot afford to pay Mercedes-Benz enough to place our stickers on the cars" and also, if the USA dealers aren't getting Liquid-Moly in bulk for oil changes, it would send confusion to the owners: why are you recommending Liquid-Moly when the dealer is using Mobil1? That is a peculiar situation.

So, Mauro and others so situated: if you can get a proper grade of oil in your local market and be assured it has the right zinc and phosphorus additives in the proper quantities, don't worry about the brand. We may never have heard of it here in the USA. Motul, Coffin, Halfords, Ravenol, Petronas are all oil suppliers known in their respective markets with little to no presence in the USA. That fact--not available or scant in the USA is irrelevant.

[MikeSimon]

Regarding engine oils in (current) German cars, we had this little discussion here. I learned something new.

https://www.sl113.org/forums/index.php?topic=36241.msg264877#msg264877

[dakman29]

Kendall GT 20-50, harder to find but all I use

[MikeSimon]

Kendall GT 20-50, harder to find but all I use

+1!

Mobil is part of Exxon Oil.

[Ed Riefstahl]

Hi folks,

I believe it's very important to note that Rotella is one of the ONLY oils left on the market that still contains ZINC. These older cars from 50's, 60's 70's were designed to run on oil that contained zinc, an important lubricating additive. Possibly that's what John is referring to - ZDDP. I'm not familiar with that term though.

I believe most folks are not aware that ZINC has been removed from most oils because zinc damages catalytic converters. It is widely favored for high compression diesel engines though, because of its lubrication qualities. I've been using Rotella T, 15-40 in all of my diesel tractors and antique cars for decades.

Just my 2 cents worth.

Ed Riefstahl

1966 230SL (Ms Magoo)
1970 280S (Miss Daisy)
1989 300SE (Majestic)
1999 BMW Z3 5 speed
1991 BMW 318I 5 Speed
1997 Toyota Paseo Convertible - Red 5 speed (have you ever seen one?)
1997 Ford Ranger step side (Mater)
2023 Mazda CX 5

[MartinK]

Keep in mind that MB recommend by the owners manual a 10W30. If somebody uses a SAE40 may be alright but what the hell should a 50 or 60 grade improve?

The weakest point is the camshaft. It is not lubricated by pressurized oil. It flushes down from the oil pipe from above the cam.  And if the oil is too sticky, the flush rate in liters per minute is with a 60 grade worse than with a 40. I have seen several engines with seized or grinded cams. And it was never a matter of too less ZDDP, It always was a matter of too less lubricant.

A standard ExxonMobil Super 2000 10w40 contains around 1000ppm ZDDP (for those of you who are scared by a ZDDP level less than 1000) and fulfills the MB sheet recommendations.

Have a nice drive always. ..

Martin (operating the M127.981 with Mobil1 FS 0W-40)

[Pawel66]

Mauro, if I may - I think what you can find in Europe is Valvoline 20W50 VR1, checked for ZDDP content to protect the camshaft.

As for servicing by Mercedes - I do some jobs at Mercedes, e.g. suspension when I had to remove springs, exhaust pipe when I needed high lift, steering when I needed alignment, etc.. But then I always was there working together with the Mercedes technician with BBB in my hand and all special tools brought with me.

All maintenance and 95% of the ad hoc jobs I do in my garage, my mechanic helping me sometimes. The biggest topic was disposal of used engine oil - I had to make arrangement with a nearby shop to take it from me to utilize properly.