Use a synthetic, preferrably Mobil 1 0w-40.

It's the 21st century.

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Kent Christensen
Albuquerque
'07 GL320CDI, '10 CL550. '01 Porsche Boxster
Two BMW motorcycles

I think in this case i would recommend the synthetic as well.... at your mileage you would just have to change it once a year....

i use a lot of different weights...so I wouldn't know...everyone seems to be going towards that 0w-40... i would think 10w-40 would be just fine as well.

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1989 300ce 129k
( facelifted front,updated tail lights, lowered suspension,bilstein sports, lorinser front spoiler, MOMO steering wheel, remus exhaust,stainless steel brake lines). (Gone)

1997 s320 154k (what a ride). Sold with 179k miles. Replaced with Hyundai Equus

1994 e320 Cabriolet 108k



1972 280se 4.5 153k Owned for 12 yrs, sorry I sold it


[/SIGPIC]

Rotella T is a fleet oil, formulated to be compatible with either gas or diesel engines. The "T" stands for turbocharger, to prevent coking of the oil in big turbos in large diesels. It seems like a bit of overkill for a gasoline car that gets driven 6,000 miles a year.

Mobil 1 0w40, change it once a year.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I used to put only Mobil 1 0-w-40 in my m119 4.2, till one day i heard rod knock as I was starting the engine (over 40c ambient temperature at the time).

Since then I've been using 20-w-50.

I tried Mobil 1 synthetic one time. My lifters were noisy as hell! I went back to my tried and true Castrol 20-50, and all was better. Ive been using it for the last 100K religiously, and no problems. I run 10-30 in the winter time, however.

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93 300D 2.5 Turbo, Black/Palomino 273K
09 E350 Black/Black 41K

I agree. M1 is the way to go.

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"I have no convictions ... I blow with the wind, and the prevailing wind happens to be from Vichy"

Current
Monika '74 450 SL
BrownHilda '79 280SL
FoxyCleopatra '99 Chevy Suburban
Scarlett 2014 Jeep Cherokee
Krystal 2004 Volvo S60
Gone
'74 Jeep CJ5
'97 Jeep ZJ Laredo
Rudolf ‘86 300SDL
Bruno '81 300SD
Fritzi '84 BMW
'92 Subaru
'96 Impala SS
'71 Buick GS conv
'67 GTO conv
'63 Corvair conv
'57 Nomad

It is the 21st century, which of course is going to hell in a handbasket on many things automotive, including many monuments to cost cutting such as the development and production of engines that absolutely require synthetic oil or they go into the business of producing oil sludge. But you are indeed very fortunate to have one of those great 20th century engines, one of that century's finest, that is unfinicky on the question, a fact which is reflected in MB's recommendations on the subject. I would go with the 15/40.