Hi ,

I just bought a 450SL. The owner's manual recommends 10W 40, to 20W 50 oil. Since this manual was printed in 1980, and there seem to have been many advances in oil since then, is there a recommended oil grade to use?

John

here we go again!!!!........

__________________
'95 s500 (bought for wife but can't bear to share!!!) 125kms
'92 legend 180kms
'88 tbirdturbo(fantastic car-only regular maint.)120kms
'87 mustang gt(gone)
'86 tbirdturbo(gone)
'85 mustang gt(gone-but not forgotten)

The manual is correct, 10-40 is a good choice, unless you live in Arizona or Nevada where the temps have been running in the hundreds then 20-50 would suffice, even boring 10-40 is better than it was 20 years ago so you can still take advantge of oil technology, or go out on a limb and try synthetic, thats what I run, you can go a little longer between changes.

Congratulations on your new ride. I run Mobil 1 15-50 during the summer months. It's on the approved list. Have fun.

sbr
'79 450SL
77,000 miles
Milanbraun/Bamboo/Chocolate

I live in Arizona and use 15W-50 Mobil 1. But guess what? I also used it in Minnesota!

It should be noted that the so-called economy oils (5W anything) recommended by big auto companies will hardly show any improvement in fuel mileage over higher viscosity oils and the real reason Ford and others recommend this crap is to permit them to report higher CAFE averages to the US government. Ford has now gone so far as to recommend 5W20!

German car manufacturers have stuck to recommending oil that's best for the customer.

I believe that M-B now recommends using 0W-40 synthetics in any gasoline engine manufactured since 1998 and 10W-40 and heavier synthetics in earlier cars. I believe they specifically recommend not using 0W30, 5W-30 or 10W-30 even if it's a synthetic.

check the cars records and use that as a guide to oil preference.i'm with BUD -if you're going to synthetic(especially if prev. owner hadn't used it!) make sure you go with a heavy one-stay away from 5wxx or 10wxx.when i got my mb i also wanted the best and i changed to 5or10 weight synthetic,but because my p.o. hadn't i ended up leaking at the top end-not much but i hadn't leaked at all before or since.i'm sure someone can give you the technical explanations but i figured the seals and rubbered bits dried out and shrunk and this let the thinner flowing oil past.

__________________
'95 s500 (bought for wife but can't bear to share!!!) 125kms
'92 legend 180kms
'88 tbirdturbo(fantastic car-only regular maint.)120kms
'87 mustang gt(gone)
'86 tbirdturbo(gone)
'85 mustang gt(gone-but not forgotten)

Believe it or not, there are 2 5W-30 synthetic oils on the approved list. However, they are oils that are not sold here. I agree that European car companies are more interested in engine protection than fuel economy. You will be hard pressed to find a European engine that calls for anything less than XXW-40. My VW Passat calls for 5W-40, and only to use 5W-30 if 40 is not available. I use Valvoline Synpower 5W-40 (A3 rated) For a good conventional oil, I would go with Castrol 10W-40 every 3K, for your V-8.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member

John,

Use the search feature type in 'oil' when you get done reading the posts next April, I am sure you will conclude to just do as the owners manual says.


thebern

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1982 240D 313,000 (4 speed)
1984 300CD 172,483
1985 German Shepherd Dog -Lacey- R.I.P.11/04/05

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