A mechanic seems to have used engine oil to lubricate throttle linkage. Is it good?

I think it is engine oil because the spill under the linkage onto engine has the same color as the spill around breather hose and oil fill cap.

The MB maintenance CD file suggests "only ATF" to lubricate those linkages.

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1992 300D 2.5 turbo diesel. 319 k miles.
124.128 chassis, 602.962 engine, 722.418 tranny.

i would use atf as recommended by mercedes, or disconnect each ball socket and apply some light grease to both sections

You may have plactic parts in the female side of the connectors, but I'm not sure about the W124. If this is the case, engine oil will deteriorate the plastic. I like to use silicone-based brake grease. I pop off the female end, coat the male end and snap it back together. All the grease stays in the fitting and doesn't leave a mess like ATF.

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1982 300D, black w/ palomino leather, 203K
2001 E320, champagne, 105K (Mom's)
1999 Dodge Dakota, squeaky & battered, 142K

I used atf like MB says to, but a light grease is probably better.

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

At the auto supply you can get a lithium grease in a spray can. Use the small tube and pinpoint it to shoot into the joints, then wipe off the excess. This will be quick and easy, stay in place well and not harm plastic parts.

Good luck,

Thanks.

Some linkages could not be easily accessed due to some complicated things on the driver’s side of the engine.
I bought a long brush at art supply store and used ATF. There were still difficult to reach linkages, so I sprayed lithium grease there. I could not wipe off excess there.

I am not sure whether this is due to linkage lubrication or some other factor, but after the lubrication, 1 -> 2 up shift is a little bit less hard.

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1992 300D 2.5 turbo diesel. 319 k miles.
124.128 chassis, 602.962 engine, 722.418 tranny.

Maybe he used ATF. It looks the same as oil. Try wiping some up on a paper towel or rag and smelling it.

I use lithium grease. Where the ball and socket joints can be separated I separate them, wipe them off, put in a dab of grease the size of a match head and snap the joint together. In pivot points that don't come apart I spray in lithium grease from a spray can.

But if the manual says use ATF then next time I will get an oil can, fill it with ATF and give all the joints a shot. Then wipe up the excess.

Interestingly enough I was lubing the throttle linkages today on the 300D (had never done it before) and now I across this thread.

The diesel pedal seems to have a smoother action now, except the transmission now won't downshift, and if I dont hit the kickdown switch, the engine will rev only to about 2200 RPM through all the gears and be very very reluctant to go past that unless I force it to downshift with the shifter...I used valvoline chassis grease, perhaps I went overboard/used too much? Anyways it's too dark out now I will have to check it out tomorrow afternoon, maybe one of the linkages didn't seat back down properly or something.

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1985 CA 300D Turbo , 213K mi

Perhaps you somehow knocked the bowden cable loose?

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1982 300D, black w/ palomino leather, 203K
2001 E320, champagne, 105K (Mom's)
1999 Dodge Dakota, squeaky & battered, 142K

I figured the Bowden Cable was the linkage with the squiggly rubber boot thing around it, and it is connected... though I noticed it pivots and I need to play around with it... i hope i didn't somehow change its adjustment.

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1985 CA 300D Turbo , 213K mi