No difference in camshafts in 2.6 or 3.0 liter M103 engines.

Using a 10W-40 or 15W-40 doesn't matter in So Calif.

However the lighter weight oil will allow better lubrication in cool weather.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
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MB technical information Specialist (15 years)
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I read somewhere that in 1989 MBz changed the camshaft profile for a smoother idling engine (M103), as the earlier cams were known to idle a little rougher than the new ones. That may be what the FSM is referring to in the mid-1989 production change that ps2cho mentioned. Does your response above mean that a 89+ cam (and rocker arms) can safely be used in a pre-89 M103 motor, or only that a 2.6 and a 3.0 use identical cams, provided they are of the same model year?

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1988 California version 260E (W124)
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Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

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