When I got my 300D the oil was likely upwards of 3 or 4 years old. I changed it with Valvolene Blue the following day as that's what was handy and new dino oil can't be worse than super old oil.

I'll be going with M1 in the future, but I have a question: the local car parts store carries M1 but *all* the bottles say for gas engines...
Thinking I'll be needing to special order some?
-nB

__________________
'83 300D Turbo
Current: ???K mi - 19.2mpg -> 17.4mpg -> 22.9mpg ---> ODO Died
bought at: 233.8K mi - 10MPG For $1.00
3.5 cylinders work: 320 320 100 340 280
Got insurance? FarmersReallySucks.Com

Is that Mobil Delvac 1 or just Mobil 1? There's a big difference and I'd strongly recommend you go with Mobile Delvac 1, which is typically not found at the McParts store.

__________________
-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

If you keep your oil changes to reasonable periods, the regular Mobil 1 (as long as it is rated for Compression engines) is fine ... Delvac is better, but most (not all!) of the "better" is in its ability to suspend particulates.

__________________
George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg

You have to be careful with that. Most of the "regular" M1 won't have a rating for compression engines. Some of the one's that do have a rating will have an older rating..............CF or so.

If it doesn't have CH or CI, you don't want it.

One thing I thought was pretty cool was Lucas Long Drain oil sold at Auto Zone, etc. I don't think it replaces oil, it's just added in with oil, I think. The oil clings to the gears for a longer period of time, so there's less
metal-to-metal cold starts.

jeff
1991 300d

It also makes a very nice foam!
http://www.bobistheoilguy.com/images/lucas/lucas.htm

Just Mobil 1, not sure what ratings it had...
What should be the change interval if running M1 Delvac?
I appear to be burning almost no oil (2K miles and the oil is down > 1/2 quart)
-nB

__________________
'83 300D Turbo
Current: ???K mi - 19.2mpg -> 17.4mpg -> 22.9mpg ---> ODO Died
bought at: 233.8K mi - 10MPG For $1.00
3.5 cylinders work: 320 320 100 340 280
Got insurance? FarmersReallySucks.Com

Less than half a quart you mean?

The change interval is up to you and your engine. I change mine at 6k (603 engine) and I change my Golf at 10k (02 TDI).

__________________
-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon

Yep = regular with caveat, as stated, that it is compression engine rated ... key issue is the change intervals.

I change my 603 at about 5-6K ... I end up adding a bit more than a quart between changes (hasn't changed much since I first bought the car at about 95K miles).

I am reevaluating my position on using Mobil 1 ... mainly due to cost ... I know it sounds like rationalization, but I continue to hear good things about the quality of products like Rotella Syn and even the Walmart branded synthetics - perhaps a "better-than-dino-but-slightly-less-good-than-Mobil-1-since-it's-quality-is-decreasing-while-it's-cost-is-increasing-too-so-just-change-10%-more-often" option might be reasonable for diesels since they need to get rid of particulates?

Comments on this approach - or, rash over rationalization to the increase in Mobil 1 price?

__________________
George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg

Thanks for the mountains of info, guys, as always. It's been good reading material for the past few days, all these old threads out there. At this point cost is not a concern for me. I don't put enough miles on my car that I need to do any more than four oil changes a year, and the extra cost of synthetic just would not add up that much. It's not like my dad's truck, which takes 12 GALLONS of oil on each change!
My only concern is the leaking issue, even though the consensus seems to be that it isn't something to worry about. I do have some leaking from the front crank case seal, enough to leave a drop on the pavement each day but not enough to cause any major concerns. I've had a couple mechanics check it out and say not to worry about it. But it's definately there, as well as some other miscellaneous leaks, and I don't want to put myself in a situation where all of a sudden I have replace a whole pile of seals at once. My general feel, though, is that that isn't going to happen. I'll double-check with my indy next time I talk to him If he thinks it's OK, and so many people here have had success, I think it would be a good move for my Bodhi.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

That's my philosophy.

If you're going to change it every 5-6K, why spend $6.00 per quart on M1 when Rotella syn will do exactly the same thing for $4.00 per quart.

Naturally, if you need to run M1 in a 603 due to lifters or other issues within the engine, then the additional cost is not meaningful. I'm contemplating switching to M1 on the '86 because there is one lifter that simply won't stop its intermittent tick, even after 30K on Rotella syn.

But, the 617 will never see M1........just not worth the cost.

Oil in Detail or: "Everything You Want to Know about Oil but Are Afraid to Ask."

__________________
1999 E300DT (131,800) 154,000 Black on Black SOLD

2006 CLK 500 coupe Capri Blue on Grey (zoom,zoom)
47,000mi

04 VW TDI Passat 80,000mi
(Techno)

How to eliminate oil dependency through market-driven approaches.
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The Sound of Diesel Speed
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