A Few quick Questions, Can Mobile 1 synthetic be used for both Diesel and Gas?,What Weight Oil should i use (temp 50-115)?,What is the change intervals using synthetic? and what designation (eg SJ for gas)is used for diesel.
Thanks.

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1979 300D.

Yes, but I now used Shell Rotella 5W40 synthetic. It's a diesel formulated oil.

You could use SOS oil analysis, but I'd change it at 10,000miles.
At this age/mileage though, the question arises, why are you switching to synthetic now?.

.

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[http://languageandgrammar.com/2008/01/14/youve-got-problems-not-issues/ ]

"A liberal is someone who feels they owe a great debt to their fellow man, which debt he proposes to pay off with your money."

This has been the subject of much discussion, but the quick answer is yes, many people use Mobil 1 in their diesels. The correct designations for diesels begin with "C" (as in compression), these include CI-4, CH-4, CG-4, CF-4 and CF. Most people run 5W40 in older diesel. The Mobil 1 5W40 was formally available as "Truck and SUV" but is now being repackaged as "Turbo Diesel Truck" oil. As a result 5W40 is a little hard to find at the moment.

Mobil's current synthetic diesel oil is Delvac 1. I run it in my diesels and one of the gas vehicles.

- Jeff Miller
190DT

mobil 1 synthetic is the way to go and right now there
are people using duel remote filters and going 100,000 miles
between oil changes.... (they will change filters and every 10k send
off an oil analysis)

Costco is selling 10-40W Mobile 1 with the CF designator, do i need 5-40W in a climate like Los Angeles or would even a 10-30W do in this climate as long as it had the CF

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1979 300D.

I didn't know they had a 10W40 synthetic?

http://www.mobil1.com/USA-English/MotorOil/Oils/Mobil_1.aspx

Are you sure its not Mobil petro oil?

You should take a look at the manual, but I think 10W30 is going to be too thin for LA in the summer. Hopefully the new 5W40 will turn up soon.

Maybe i missed read(glanced) at the oil

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1979 300D.

Mercedes recommends Mobil 1 0w-40 for the newer diesels. I've had good luck running RedLine 15w-40 synthetic in the older models.

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"Red Line Oil; Slicker than snot and twice as tasty!"

[QUOTE=Craig]I didn't know they had a 10W40 synthetic?

http://www.mobil1.com/USA-English/MotorOil/Oils/Mobil_1.aspx

I was looking at the oil section in the local Wal-Mart (in Canada), and I noticed that Mobil 1 15W50 is no longer available, and appears to have been replaced by Mobil 1 5W50 ! This oil does not appear in the Mobil 1 website. Have any of you seen this oil in the US? Could it be a Canada-only formulation?

I'm concerned that a 5 weight oil will not be viscous enough for summer starts. Perhaps I'll have to switch to Delvac.

Just for fun, I tried out the "What's the right oil for my car?" section of the Mobil website:

http://www.mobiloil.com/USA-English/MotorOil/Car_Care/Vehicle_Chooser/VehicleChooser.aspx?option=1

I was surprised to find that Mobil 1 0w30 is recommended for my 1987 300SDL. I think I'll stay with at least a 15w40 oil, and ignore the Mobil 1 recommendation.

0W30 is OK for winter use in cold climates, but I would not use it south of Chicago. I used the 15W50, but it is no longer C rated for some reason -- use the C rated mobil 1 and you will be fine.

For diesels, you must use something with a C-rating (current is CI-4), and on any of the older ones, you MUST use CH or CI rated oil to suspend enough soot to make it last long enough -- the older engines soot up faster. If you want to do extended (more than 3000 miles) oil changes, get the oil tested and watch the soot % number. Change before you get to 4% -- it will get flagged on the report when it gets high.

For 60x and newer diesels, 6000 miles is what I aim for, often run more. No problems at 240,000 miles.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Has anyone seen a motor destroyed due to lack of oil changes or the use of dino oil?.....among car enthusiast owned cars, gasser or compression?

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82 300D....went to MB heaven
90 350 SDL....excercising con rods

Most engine failures I've seen were lack of lubrication or failure to keep dirt out (cutting the emissions control vac lines and leaving the source end open seems to have been an epidemic around here 20 years ago).

Scored bearings, huge sludge accumulation, galled cams, flat lifters on US engines, scored cylinder walls, you name it.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

I'm not sure, the US web site does include Mobil 1 "Extended Performance" 15W50:

http://www.mobil1.com/USA-English/MotorOil/Oils/Mobil_1_Extended_Performance_15W-50.aspx

but does not seem to include any 5W50. Lots of folks are using 5W40 synthetic including Mobil 1 and Delvac 1. For what it's worth, the Mobil web site also says I should use 0W30 in my 617/616 (I don't think so ).