I was at AutoZone yesterday, was playing with the little oiled gear display they have, where you crank one compared to the other to see the difference between the 2 oils. The clerk had to go to the back for something, so to amuse myself, I kept playing, and playing, and playing with it, but noticed no difference between them, other than the one stuck to the plastic gears better.

When he came out, I said, I've been turning this thing like crazy, but don't notice any difference. He said, you're not supposed to. The oils both feel alike, but one lasts a lot longer, and it works in gas or diesels.

I called the company, Lucas, to check his story out. They said their 15/40 "Magnum" Long Drain Truck Oil can be used in cars, and will last a MINIMUM of 15,000, without breaking down, due to it's high TB Number, but I forget what TB stands for. He said you could actually go 20,000 miles, but they cap it off at 15,000. Said you'll be perfectly safe doing that. I think he alluded to the thing that they have some way for you to test it along the way so you can see for yourself that it's still protecting your car. Check 'em out on the web for more info.

Rotella has been highly recommended by a lot of you dieselers out there, but if I can go a whole year on one oil change, guess what I'm doing? Mind you, the stuff is $6 per quart, but it's less work and less expensive in the long run.

...and now an update since the original post, above which was written a few months ago. I contact Lucas this week, talked to a different person, got a different answer. He says Lucan Long Drain Oil will help give you about another 1,000 miles on an oil change, and most importantly, protects your engine from cold starts where it's just metal against metal. He says it will make a big difference in life of the engine.

jeff
1991 300d, 90k

In Diesels you change the oil to get rid of the soot in it as much as you do to keep up its lubricating properties. Someone here tried doing a 10,000 mile oil change and sent their oil off to be analyzed. It came back with the soot levels too high. I wouldn't try going 15,000.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png

Regardless of the condition of the oil, its the contents of that oil I'm more concerned with.

I change my oil every 6-10k.

The company said it's the highest number, by far, for TB, whatever that stands for, which is why it can go for so long. Their brochure says it's for diesels as well as gas. "Guarantees a cool, quiet performance with extended drain intervals, longer engine life, and no dry starts". I think I'll call them tomorrow, talk to someone higher up on the totem pole. But even with their little plastic turn wheel, you can see how the oil sticks to the gears much better than regular oil. ... I just wonder how good their guarantee is.

Even if I went longer on the oil changes, that brings me to the next question, how long can an oil filter go before needing changed?

1991 300d, 90k

just get yourself a frantz oil filter http://www.utterpower.com/oil.htm

__________________
green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

http://ecomodder.com/forum/fe-graphs/sig692a.png

That was me, the oil analysis indicated that the oil was still good (TBN of about 6) after 10,000 miles, but the soot level was high, resulting in increased viscosity. The TBN is a measurement of how much of the oil's additives are still left:

http://www.blackstone-labs.com/do_i_need_a_tbn_.html

The problem is, I still need to change the oil more frequently to get rid of the soot. The oil change interval is not being limited by the quality of the oil you're using. If you want to extend your oil changes, have the oil analyzed after about 5-10,000 miles and you will get an idea of what you can get away with. Personally, I use good synthetic and change the oil/filter every 5000 miles.

TB = thermal breakdown. Not something one worries about unless you are racing or have a turbo (gassers run hotter). I use regular Rotella diesel oil, it analyzes well for soot and viscosity at 4000 miles, so that's what I use.

__________________
'83 240D with 617.952 and 2.88
'01 VW Beetle TDI
'05 Jeep Liberty CRD
'89 Toyota 4x4, needs 2L-T
'78 280Z with L28ET - 12.86@110
Oil Burner Kartel #35

http://i16.photobucket.com/albums/b1...oD/bioclip.jpg

If you watch for sales, oil and filters are just not that expensive and it's the best way I know of to ensure a long engine life. Oil to an engine is like blood to an animal -- you've got to keep it clean. My last change cost less than $17 for two gallons of Delo-400 and a Turkish Fram from the last Pep Boys sale.

Oil changes are also a good opportunity to do some bonding with the engine and see what has fallen off since you last crawled under!

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

I'd heard before that Frams are no good unless you get the ones from Turkey. Basically, I'm under the impression fuel filters have life easy. I'm assuming you could change the oil every 3,000 miles, but use the same filter for 20,000 miles and your engine would not be any worse for it. I mean, how many bad particles are in oil?

jeff
1991 300d, 90k

The problem is that you don't know. If the pressure on the element reaches a pre-set (and fairly low) level, a bypass opens, and you get unfiltered oil. There is no indication of when this happens.

Soot is the enemy. A 15,000 mile oil is a great idea, but the pan needs to be 'purged' of anything in there from time to time and draining it, NOT TOP SUMPING it, is the way to remove it. At my job one of the type of products that I work with the developement of is engine lubrication components. The OEM engineers are always concerned about soot that occurs at the oil change interval mileage that is listed in the manual.

Years ago I was a faithful 2,000 mile oil changer on standard oil. Later I wnet to 3,000 miles. Now I will go 8,000 miles on a full sythetic, but no more than that. Sure I costs more that 10,000 miles or more, but replacing a 606 engine costs far more than a few more oil changes. What are you willing to risk?

Where is blueranger? He runs 20,000 miles on oil that was used in 4 cars before his MB Diesel.

LOL, don't encourage him.

I don't think TB stands for Thermal Breakdown. On the ships on which I work, we perform analyses for TBN, which is Total Basicity Number--the base (alkali) additives help to neutralize acids which can show up in used oils...

__________________
Mahalo and Aloha,
S. L. "Red" Pike, Naval Architect/Marine Engineer, USCG Licensed Chief Engineer (Steam, Motor, and Gas Turbine)
Former nuc bubblehead (boomers)
"Sustained superior performance through continuous incremental improvement."

1987 300SDL White w/ Gray Leather interior, 160K (mine)
2009 Nissan Murano (leased - wife's)

You're correct, see the link in post #6.