10/30 mobile one synthetic okay in a 1983 500Sl

[nh500sl]

Is this oil to light to run in this car in the summer in Oregon? Thanks for any info, Nick.

[meltedpanda]

call me old school, well I am but I would run regular dino in any car before 85. 10/30 is a good weight however .
all sorts of discussions about synthetic oils after a life of regular ol dino

[cwmoser]

I think Mercedes recommends 20w40 or 20w50 dino oil.

BTW, I put in Mobil-1 Synthetic in my 2000 Isuzu Trooper when it had around 140,000
miles and it had such loud valve clatter that I drained it refilled with dino oil after
about 300 miles. But, you might have a better outcome.

[Diseasel300]

Originally Posted by cwmoser

I think Mercedes recommends 20w40 or 20w50 dino oil.

I'll second the heavier weight oil suggestion. I have an '85 500SL and ran 10w-30 Dino in it for a short period when I couldn't find the right stuff (for whatever reason there was a shortage of heavier oil here at the time!)

It ran fine, had decent oil pressure, everything was hunky dory, except if it sat for more than 2-3 days, you'd hear the entire valve train make noise on the first start of the day. As soon as oil pressure built up, it would quieten right down.

Got some 20w-40 Castrol and filled up with that, and it's silent as a mouse, even when sitting for months at a time.

It's your car, you do what you want, but the thin oil made noise and noise = wear.

[nh500sl]

I do not want wear. Hmm what about the deli I 15/40 oil? It's diesel rated? What does that mean for a gas motor though?

[Diseasel300]

Diesel and Gas engines have different requirements for their detergents and friction modifiers. You want an oil made for a gas engine.

[cwmoser]

I use Rotella T 20w40 diesel oil in my two SL's because of the Zinc content.
I've read that SL's of this vintage can benefit from the lubricating qualities of Zinc.

[ejboyd5]

Why pay the premium for a synthetic? Those engines run fine (and will continue to do so) on conventional lubricants. Rotella T 15W-40 is fine product.

[karburn]

No. Use dino oil. Synthetic is too thin for the older motors that have run on regular oil since day one. Leaks will happen - maybe not right away - but still. Regular 10-40 Valvoline is what I run in the 87 560SL on the advice of a long-time MB mechanic.

[Graham]

Oh Shoot - another oil thread

nh500SL. Slightly different engine, but my 4.5L 1972 has had synthetic for last 15+ years with no ill effects. I use it because it seems to quieten down the valve train, compared with previous dino oils I used. I use slightly heavier oil 5 or 10W40. Mercedes spec for many cars is 0W40 or 5W40. On my old car, I often use the one below, if I can get it. It has higher ZDDP than other Mobil types. There are several other choices and EVERYONE has an opinion (or knows someone who does!)

Mobil 1™ Turbo Diesel Truck 5W-40

Mobil 1™ Turbo Diesel Truck 5W-40 is a fully synthetic performance heavy duty diesel engine oil that helps to extend engine life while providing long drain capability and fuel economy for modern diesel engines operating in severe applications. Mobil 1 Turbo Diesel Truck utilizes state-of-the-art technology to help deliver exceptional performance in modern low emission engines, including refrigerated units, as well as older, well-maintained engines. Mobil 1 Turbo Diesel Truck 5W-40 is recommended for use in a wide range of light-duty applications such as turbo diesel pick-up trucks, as well as, heavy-duty applications and operating environments found in the on-road transport and off-road mining, construction, and agricultural industries. Mobil 1 Turbo Diesel Truck also meets the API SM specification for gasoline engines used in mixed fleets.

[cwmoser]

Probably most important is to change your oil often.
I put only a couple thousand miles a year on my SL's if that much -- but I change it
every year. When I change my oil it still looks fresh.

My thinking is why spend extra money on Synthetic when I keep the dino oil fresh.