OK, here it goes. My daughter's newly purchased 1989 300TE had an engine rebuild at 126K (head job, new pistons, valve seals, etc.). Since the rebuild, the previous owner has used nothing but Mobil 1 oil (he even gave me a case of Mobil1 when I bought the car from him). I bought the car with 146k in the odometer and now that the car is reaching 150K I am getting ready to take it for the 150K service.

My mechanic advises against using Mobil 1 (he really doesn't like Mobil 1 or any other synthetic oil).

I figure that since the car has been using Mobil 1 since the engine rebuild, I might as well continue the "tradition."

What do you guys think?

By the way, in 3K miles the car has not consumed any oil.

I'd appreciate hearing about your own experiences in this area.

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Current Benzes

1989 300TE "Alice"
1990 300CE "Sam Spade"
1991 300CE "Beowulf" RIP (06.1991 - 10.10.2007)
1998 E320 "Orson"
2002 C320 Wagon "Molly Fox"

Res non semper sunt quae esse videntur

My Gallery

Not in this weather!

I would "continue the "tradition." "

The only issue might be viscosity. Being where you are and what MB approves, 0W-40 and 15W-50 are the only two you may want to use.

0W-40 is still hard to find. It is only available at MB and Porshe dealers and Mobile distributors where it costs an arm and a leg (around $5-8/qt).

15W-50 is easier to find (Wal-Mart).

Some people use 10W30 (I do in the winter here in Michigan) but in theory, it is not one of the MB approved oil.

Rotella just came out witha 5w-40 synthetic. I bought a couple of gallons the other day at Walmart.

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Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Use Mobil 1, maybe your mechanic just doesn't like synthetic because it takes away from his business

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Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record

I think that the "approval" is for a new car. On a car that has 150,000 miles on it I would not bother with what Mercedes approves. I think any Mobil 1 is going to be better than anything that Mercedes approved in 1989. The 0W-40 approval is more for meeting fuel mileage requirements than what is good for the car.

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Currently
1991 Mazda Miata 174000
1991 Subaru 189,000 Winter beater

got rid of:
1984 VW Vanagon 195,000
1976 350SE Euro 185,000 KM
1973 280SE 4.5 (boy do I regret that)
1980 280SE European W126 4 speed manual (miss it)
1989 BMW 735iL 119000 (good riddance)

Silver Boat:

You are right that the approved oils are for the new cars (1998 and newer). However, Mercedes also "recommend" the use of these approved oils in older model cars.

According to MB, the development and use of 0W-40 is to use only one oil in arctic or desert weather, i.e., everywhere. There is no need to switch oil due to temperature.

The key in the approved oils, to me, is that Mercedes does not like xW-30 or xxW-30 oils. As a matter of fact, Mercedes specifically say it and I quote:

"thin oils are not recommended, e.g.

Mobil 1 Tri-Synthetic 0W-30 (doesn't meet 229.1)
Mobil 1 Tri-Synthetic 5W-30
Mobil 1 Tri-Synthetic 10W-30"