15,000 mile oil changes
 

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.

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.

Soot content
 

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

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.

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 :D since you last crawled under!

Turkish Frams
 

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...

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

I am here
 

Chevron made a statement about there oil recently and they said
it it was impossible to wear out todays modern lubricants... So now there
are big rigs going 100000 miles between oil changes....

So the viscosity remains and the additives remain there are 3 additional
negative factors, water, soot, and metal particles... so people who go long periods on an oil change use bypass filtration... to take care of the
later 3 items...

the mercedes filter is suppose to have a bypass filter built into it...

I probably have 25 k miles on this oil change well over a year.... I am going to change it in a few days all because i got oil on sale.... shell rotella at home depot...


diesel oil has additives that will float the suit until you change it...in aviation they call it ashless dispersant...

basically its not your oil that needs changing its your filter

2 gallons basic oil: $14
Oil filter: $9

Four 3000 mile oil changes based on 12,000miles/year driving: $92/year
One oil change/year/12,000miles assuming 3000 mile oil filter changes: $65/year
Total saved: $27/year. 7 cups of Starbucks

Why risk your cutting short the life of your $4,045.50 (AdsitCo) engine to save a paltry $27/year!? It's not worth the pennies saved.

Stick with your 3,000mile changes. 8qts of oil is a drop in the ocean. In the past, I've changed oil everyday in trucks that use from 12qts in the Isuzu 4HEI to 5 gallons in the Cat 3126 to 9 gallons in the Cummins M-11.

For the first, these "big rigs" don't run a paltry two gallons of oil. They also always have bypass filters, and many of them even burn the lubricating oil, requiring regular top-offs, in effect slowly changing the oil as they run that hundred kilomiles.

For the second, certainly not all Mercedes diesel engines have bypess filters installed from the factory.

But let's not confuse people with facts.

facts
 

i am just giving you the facts,,,

the large diesel mercedes canister filters are suppose to have a bypass filter
as part of the actual filter...everyone here knows what a mercedes drop in filter looks like... yes, it has a bypass filter included in it..


a 90hp mercedes carrying 2 gals of oil is probably carrying more
oil than say a 1200 hp truck carrying 10gals of oil...

oil change
 

the reason i dont change my oil at 2k intervals like you boys is not
becasue of money....i view it as a waist,

why dump good oil... why enrich saudi arabia more, why polute our environment,

hey i got a great idea. lets all run veggie oil in our engines and then when we reach a million miles on it we can just dump it in the tank unheated:rolleyes:

Try 425hp engines with 9 gallons (2001 Cummins M11).

47hp/gallon (bigrig) vs 60hp/gallon (us)

"why dump good oil... why enrich saudi arabia more, why polute our environment,"

The oil is not wasted. Almost all of it is reused in powerplants, for heating, scenic steam railroads, and many other uses.

As long as you are not one of the nuts pouring it down the storm drain, very little is wasted.

"lets all run veggie oil in our engines and then when we reach a million miles on it we can just dump it in the tank unheated"
oooo, I like that idea. What's the soot capacity for soy based fryer oil?

a mechanic I know in europe drives a '78 Peugeot 405. never changed the oil. he says that if you keep filling the bit it uses, you can drive it forever. he did change an oilfilter after 12 years though. the car still runs. 576000 Km on it. His name is Marcel Du carotte and lives in Orange, France.
But then again, that's a Peugeot.
http://www.peugeot.com/en/default.htm
another guy I know does the same to a subaru. he lives in Byron Bay, Australia. '82 pickup model. I forced him to put oil in his gearbox. he was amazed by the difference in noice when driving.
also I know people that never eat fruit or vegetables and seem pretty healthy at 67.
It's confusing.

I agree.

Because of the climate, I use synthetic (Rotella) and it breaks down as follows:

3 oil changes per year based upon 15K per year

Cost of oil (6 gallons): $90.00
Cost of filters (3): $24.00

At $114.00 for 15K, the cost is basically identical to the dino.

And, since I'm lazy, I'd much prefer to do three changes than five.;)

Wow. I've haven't seen this much misinformation and confusion since....the last oil change interval (OCI) discussion.:)

1. Diesel synthetic oil will not be worn out in 15kmiles. By this I mean the additives will still be fine.
2. The issue is soot contamination with these old diesels. 2% soot used to be the level that the oil was spec'ed to handle in the early eighties. synthetic diesel oils can now handle 6% soot. If you use good fuel, and have the EGR system shut down, you won't get 6% soot in 15kmiles, not even close.
3. The 3kmiles OCI is as dead as can be. All auto manufacturers have abandoned that years ago. It's only the quick oil change places that continue the myth.
4. Americans are oil change crazy. Nowhere else in the world do people waste as much oil over changing their oil, and interestingly, cars in other countries last longer. Go figure.
5. Over changing oil weakens America, pure and simple. It's bad economically to throw out good assets before they are no longer doing their job, and it certainly is bad for the environment. I'll let you decide if more money in the hands of the Saudis, Iranians, Kuiwaitis, etc is a good thing or a bad thing.
6. The good news is the myth is broken. Enlightened people all over the country now understand the cruel trick that has been played on them, and are changing their habits.:)


240Joe

It is actually TBN.

TBN stands for total base number which is the oils ability to fight off acidity.

Motor oil becomes acidic and the higher tbn the longer the oil resists this.

Steve

Please publish the results of your used 15K oil analysis to support this claim.

Craig,

There is lots of data out on the web on this subject. Go to www.bobistheoilguy.com and search there first.

I don't do oil analysis. You're better off spending the money on oil.

To quote an old folk singer your dad or mom might now, Bobby Dylan....You don't need a weatherman to tell you which way the wind is blowing.

240Joe

Bobby? I've never heard him called Bobby before. ;)

Do yourself a favor and get an oil analysis before you extend your oil changes. I agree, "You're better off spending the money on oil." ... than an engine rebuild. I had an analysis done at 10K miles, didn't like the results and went back to 5K changes. If you don't have an analysis, you don't know what you have in your oil. Why do you think people should follow your advice without any data?

Bobby? Well I knew him as Bobby Zimmerman.

But back to the oil. You can do whatever you want with your money, but the ground you are plowing has been plowed by many before you.

And if you look for oil analysis of our engines, you will find plenty of examples. The diesel Dokter, Marshall Booth, has been an advocate of 10kmile OCI with synthetic for years, and that man knows these cars. He is the man that documented that 10kmile synthetic OCI produced less timing chain stretch than 5kmile OCI with dino oil.

The advantage of fully synthetic diesel oil is no longer rumor. It is fact. If you're not confortable with longer OCI without sampling, then sample.

I'm happy doing what I'm doing.

240Joe

Whatever works for you.

I agree that fully synthetic diesel oil is the way to go. I use Mobil 1 5W40 (when I can find it) and I have extended my oil changes from 3K to 5K miles, based on analysis results. My results do not support going to 10K. I would extend more if it was prudent, but I'm not happy with the numbers.

I believe that on your car, it does. On my car, everyone here (except you) also knows that there is no bypass filter in the factory filter element.

Our cars don't have bypass filters. MB's elemant is a joke, no better then a little spin on.

A real by pass filter is a Frantz, or something similer. These filters actualy filter soot out. This is the limiting factor. You can do 100k+ mile changes on your MB, provided you use a Frantz filter, and have lab test it several times.

There is a bypass section of the filter. It's the large upper part of the element.

It's NOWHERE near as effective as the toilet paper based filters. It's not much of a bypass filter, but it's better than only a full-flow filter. The wound string filled filters are close, but can't filter down to the 1micron level to catch most of the soot. The Cotten gin waste filters are pure trash.

Near the top of the oil filter cap stem is an orifice to limit flow through the bypass section.
http://img.eautopartscatalog.com/live/A600030745BOS.JPG

Craig,

The recommended OCI is 5kmi so you haven't extended anything....you're back to the spec they used with 1980 technology oil....the stuff that could only carry 2% soot.

I'd like to know what you aren't happy about in the oil analysis that leads you to believe you can't extend further. If there is something there, I suspect you have another, perhaps more pressing, problem.

After all, oil analysis was used to detect engine problems along with extending OCIs.

240Joe

My car lacks that. It has the 606 engine.

The 91 300D 2.5T that the thread starter has, does.

As for you, well, you are out of luck.
http://img.eautopartscatalog.com/live/A600252872MAN.JPG

I'll give you both points.

The image is of the exact filter I installed a few days ago. These filters stick hard to the cap when you want to change them. It scares me taking them off.

I'm seriousely considering putting a bypass filter on my car, but I'm probably going to wait until the valve cover has to come off for something else first, so I can drill into it for a return line at the front.

My soot levels were up to about 0.5% and the oil's viscosity was up to about 84 SUS @ 210ºF (the spec is 65-76) after 10K miles. I'm not interested in running anything close to 2% soot, and I want the oil's viscosity to stay within the original specs. The Iron content was also a little high compared to the averages (which were based on about 5K miles). The analysis didn't indicate any engine problems, just too much junk in the oil.

I'm still pretty comfortable extending to 5K miles with a good synthetic, but I wouldn't consider exceeding 3K with any petro oil. IMHO, extending much beyond 5K with synthetic (with my engine) would require installation of some additional filtering.

Again, you should do whatever works for you. ;)

I agree, Craig. I am comfortable with Rotello non-synthetic running about 3K miles between changes. I'm confident that an analysis wouldn't show anything out of line.

Craig,

You're still missing something very basic. I'll try again. The factory spec OCI is 5kmiles not 3kmiles. Check your manual.

If you are saying you had 0.5% soot at 10kmiles, you're golden. That's darn good. And the visocity numbers look good also.

At the risk of sounding harsh, I think you're being way too picky with the oil analysis.

You have just made my case that 15kmiles with a synthetic is a NO BRAINER.:D :D

Thanks
240Joe

I know what the factory OCI is, and I still think it's too long for petro oil. For me, 0.5% soot is just not acceptable. I still don't know why you think 2% is OK, do you have a reference for that value?

I'm really not trying to change your mind on this, you should do whatever you want. Why don't you run 15 or 20K and publish your oil analysis results? I would be curious, just not curious enough to abuse my engine.

How do you test oil?
 

Thanks everyone, for this enlightening conversation.

Since I'm new to this, I hear everyone talking about they check their oil for soot levels. How do you check oil for this and other important data? I didn't even know one could do this, thought it'd have to be sent to a lab.

Thanks,

Jeff
1991 300d

i've read this thread and i've done a lot of oil analysis. i'll begin by saying that 0.5% soot after 10k in 240D or 300D is fantastic. any diesel oil, even petro, can easily hold 0.5% soot in a safe harmless suspension.

also, do you know what the SUS viscosity of the oil you used was new? i ask because 0.5% soot will not cause a significant increase in viscosity. FWIW a SUS viscosity of 84 just above 40 weight range.

if your oil contaminant levels are causing your viscosity to increase - check the two primary contaminant sources: air and fuel.

be sure your air filter is in good shape and their are no leaks in your air intake system. unfiltered or poorly filtered air will contaminate your oil in a hurry.

use reliably high-quality and clean fuel sources when possible, and be sure all three fuel filters (tank strainer, pre-filter, and spin-on) have been changed at their regular maintenance intervals.

cheers!