My wife recently purchased a very nice 1979 450SL I changed the oil and filter and poured in the recommended 8 liters of oil. I check the dipstick and it reads well over the full mark, what gives?

 

The Oil tank is "only" 7.5 liter with oil filter change!!! Please do not overfill, as this might cause engine damage or cause oil to be spitted out (hopefully) on the ground.

Drain out extencive oil. Measure with dipstic at cold engine on a flat surface!
-The book always says a number of oil "with filter change"(and this is 7.5liter - now way 8.0litre!) -and normally you always replace the oilfilter, but even then, the replace oil liter seems often to be to high. I guess this number is due to a totally rebuilt engine. I would guess 7 liter is ok to start with. On your car, drain one liter from the 8liters, and check the dipstick again after waiting a bit. -It's often better to have the level too few than over-filled actually. I'm a car mechanic and know this is true. The level aren't too low until the oil pressure drop (meaning now oil are circulating to the top and other bearing, then you MUST shut the engine off "immedently"!). I got an 1971 450SL, and it uses very little oil compare with age. It uses about 0.5liter per 800km. Please do me a favour and check your oil level every second week, as I do, and I drive very little with this buitiful car. (got another car for daily use)

... If you're interrested in my car, continue to read: I have had off totally four sylinder tops, and feel like I know what's about it. Normally the engine is made of steel (old cars), but the top is of aluminium. The temperature expand/retract mishmashes is no good if the temperature differ more than 70deg.centigrade! The alu. expand much more than steel and will twist! Therefore the flexible gasket will start to leak - either oil leak, or water into oil (really bad, because cooling fluid is the opposite of oil smeering!!!!). The most normal is that oil is leaking first, because the oil channel is at the most outhern part of the engine. I rebuilt my older C class (1994) because it was leaking oil, but also because it was running too hot in the summer. I found out it was not only leaking oil out, but also water into the sylinder! After making the sylinder head milled, and replaced a new sylinder gasket, it runned perfectly - no shake att all at the gear leverel.. Unfortenately I had to change it out for another car, as my dad gave me his "old" Renault Laguna 1.6!!!!!!. - So I bought a 450SL for having a nice, buitiful sommer car!

 

I also have a '79 450 SL and will be changing the oil for the first time. The grade of oil in the owner's manual (not the weight) is obviously outdated. Is there any concern with using the right grade of oil from today's manufacturers or will just about anything off the shelf do?