sounds like oil additives do deplete with use

[Texas Diesel]

http://www.lube-tips.com/trivia/20030910.asp



I wonder if oil analysis' check for the rust inhibitor depletion.

 

[illflem]

Yep, that's why extended drain intervals only work if you change the filter at the regular interval. The makeup oil replenishes the additives.



Is there rust inhibitor in oil? Seems like oil is a rust inhibitor in itself.

 

[Texas Diesel]

Been thinking about what you said.



If you replace the oil filter at 5 k miles, you are only replacing 1/12 of the additives you would replace if you did a full oil change.



I've been thinking about using Royal Purple Synthetic and changing filters @ 5k & 10k and oil & filter @ 15k.

 

[y-knot]

You are missing the whole point on extended oil changes. Synthetics do not brake down like conventional oils do, BUT they get just as DIRTY. What good does it do to leave your oil in there for 10-15k miles if it's just goin to get 3-4 times as dirty? You have to change the filters out more often or you will not be getting the proper effect. It's is a very easy job, spin off filter, add oil to filter, spin filter on, start truck, turn off truck, check oil level. 5 minuets, no big deal. This will also take care of any worries about additives. Diesels by nature make very dirty oil, fuel,soot, ect, all by-products of combustion, so no oil is going to solve the dirt problem. Synthetics are wonderful, they reduce friction, heat, and hold up better under high termal environments. But they still need to be kept clean.

 

[RustyJC]

Yes, additive packages are depleted, and, yes, oil does wear out. Actually, it experiences oxidation, nitration, molecular shear that results in changes to the viscosity index, fuel dilution and any number of other degrading factors.



Rusty

 

[Jacobs]

T D



You should have no problem doing a 5-10-15 type program. Try it and sample the oil as you do. It is a good idea to get a sample before you switch as a baseline.



My '95 has 190,000 miles on the clock. I have been using 15-40 Royal Purple since 40,000. I change the oil filter every 6,000 and the oil every 24,000 which figures out to once a year. I have been doing oil analysis each filter change. The Petroleum Technologies recommended changing the oil early on three occasions. Once for excessive fuel dilution of the oil caused by a leaking transfer pump. Once for excessive oxidation, didn't get around to changing the oil until about 32,000 miles. The third time it was due to excessive silicone, turned out I had a loose clamp between the air to air cooler and the pipe going to the engine intake.



My truck uses 1-2 quarts of make up oil plus the quart in the filter when I change it. I use the truck as a daily driver and pull a 32ft travel trailer once in a while.



Good luck



Bruce

 

[illflem]

Originally posted by Jacobs

The third time it was due to excessive silicone, turned out I had a loose clamp between the air to air cooler and the pipe going to the engine intake.

Bruce, I don't doubt you but this is something I've always wondered about.

If you have a leak after the turbo it seems like pressurized air would leak out, not dirty air in.

Did tightening the clamp lower your silicon levels?

 

[keimmmo]

Years ago I worked for a Marathon Oil wholesale distributor. He preached that oil DOES NOT wear out... but it DOES get dirty and the additive packages DO wear out! He changed oil regularly in everything... and put in re-refined oil! It was a lot cheaper and met the same specs as new oil. He had good luck with it!



I have tore down several motors over the years that used synthetic oil and extended drain intervals. They were clean and showed no problems from a lack of lubrication... but they showed abrasion wear! The oil was too dirty and wore out the motor! Yes, changing the filter more often would help. But, considering what a rebuild costs in comparison to an oil change, I'll change my oil regularly!!!



Just my opinion and observations.



Steve

 

[Texas Diesel]

Originally posted by keimmmo

They were clean and showed no problems from a lack of lubrication... but they showed abrasion wear! The oil was too dirty and wore out the motor! Just my opinion and observations.



Steve

Thats good info, I would rather hear from experience than someone quoting advertising propaganda. Sounds like a bypass filter might be worth looking into. Any suggestions of what/where bypass system?



Thanks

 

[RustyJC]

Originally posted by keimmmo

Years ago I worked for a Marathon Oil wholesale distributor. He preached that oil DOES NOT wear out...

The following is from the July-August 2003 edition of Machinery Lubrication magazine, page 10:

This myth that oil can last forever is exactly that, a myth. In a few circumstances oil can be restored to like-new condition through reclaiming and/or additive reconstruction. Certain lubricants, like turbine oils, are far more suited to reclaiming than crankcase oils. Often, oil encounters enemies such as water, heat, metal debris, pressure and mechanical action that stress and oxidize it beyond repair.



Figure out how to relieve the oil from the enemies mentioned above, and you'll be amazed at how much longer your lubricants will last.

Rusty

 

[Texas Diesel]

Rusty, can you post the link so I can read the full article? Thanks

 

[RustyJC]

You may be able to access the magazine from the homepage HERE.



Rusty

 

[keimmmo]

These forums are for voicing opinions. I am going to give mine. I am not saying it is the only way and am not putting down anyone who does something a different way!



Synthetic oil IS excellent quality! Without question, it is better quality than Dino oil! However, it is expensive! The best protection for your motor would be to use synthetic oil and change it like Dino oil!!! But, that is not practicle due to the price of synthetic oil!



In my opinion, to justify the cost of Synthetic oil, the manufactors have come up with the idea of running it a longer time, thereby making it economically practicle. However, as I stated above, I have seen that lead to premature wear due to the filter plugging and circulating unfiltered oil through the motor... leading to abrasion wear.



Personally, I use Dino oil and change oil and filter fairly often. For me, I think it is the most practicle. If you have your heart set on using synthetics and extended drain intervals, you MUST change the filter at regular intervals!!! Anything like a by-pass filter that would filter it better would be a plus. To make sure the oil is good to continue running, you need to do oil analysis. If you cut corners, you are likely to do engine damage... a MAJOR expense! It just seems like a lot of trouble and expense to me to use synthetic oil!



I had a boss once who told me, "Everyone is crazy... just on a different subject. " I think he had it figured out! Without a doubt, some of you will think I am crazy... at least on some subject!



Steve

 

[ralphr]

OK, from what I have heard is 1. ) most all synthetic blends are just that a blend of petroleum base stock and addatives so they can label them "synthetic" there is no industry standrad for the term "synthetic! 2. ) read the labels and the claims most oil companies will NOT recomend an extended drain interval.



what I heard a long time ago still makes sense, (at least to me). you start with the oil in the crank case, over time you will get water in the oil, (condensation, humidity, etc. then with the hydro carbons in the fuel you get a certian amount of "blow by" into the crank case, from several sources, (rings, valve stems, etcc. . ) this mixture will eventually create hydro-cloric acid and will wear the rings, bearings, and anything in contact with the oil. this condition will dramtically increase depending on what kind of driving you do, short daily trips being the worse damage long highway trips with few engine shutdowns the least.



the folks how spend there time and money doing an oil analysis are doing the best thing for there oil and engine. ( if you only drive 5 - 10 miles a day and cgange the oil at 7,500 or even 3,000 miles may be doing more harm than someone who puts on 100+ miles per day and changes the oil at 15,000 miles. it is a balancing act that only you can answer depending on how you use the vehicle, how much you drive etc.

 

[Jacobs]

Bill



When I got my sample back, the recommendation from Petroleum Technologies was to change the oil and check my air intake system for leaks. I borrowed the pressure tester for the intake system which is a plug with a relief valve that is inserted in the hose that attaches the turbo to the cooler. I then ran 10 psi to the fitting and you could hear the leak. I pushed the hose up on the pipe on the outlet side of the cooler and tightened the clamps. No more leaks.



I did not notice any power problems when I had the leak. I did not hear the leak while driving but I may have missed that one as my hearing is not what it used to be.



Last few samples have come back ok, sample at normal intervals.



I am not trying to start a war, but I believe there is something to the venturi effect in this instance. As the air rushes past the hose, even though there is pressure above atmospheric in the intake system, pressure outside the loose hose is higher than inside at that point and allows unfiltered air to be pushed into the system at that point.



I teach a hydraulics class and the change in speed/lower pressure thing generates a lot of discussion in my class.





I do not believe I save money by using extended drains and synthetic oil. By the time you have the anaylsis done it becomes about a break even proposition.



Take care.



Bruce

 

[Vaughn MacKenzie]

I think the biggest enemies on oil in a diesel is soot and the high shear/load forces. Water and combustion byproducts (other than soot) don't play a significant role, since diesel combustion is less acidic and produces much less water than gasoline. That's why the oil in your diesel still doesn't smell a lot different than new oil after being in the crankcase for 5000 miles, while the oil in your Grand Am smells nasty.



On my 2001 Ram 2500 I ran 20,000 miles per oil change using 3 filters per cycle (approx 6-7K per Stratapore filter). I did not do bypass. I did oil analysis every 10K and the wear metal numbers were always very low, indicating the oil wasn't at an abrasive state. Also the TBN, viscosity and other numbers were well within acceptible limits.



I agree 100% with keimmo, if you leave it in there too long or don't change your filters, that oil will work against you.



I feel 15-20K on synthetic is a good interval. It's not excessively long and you get 100% fresh oil on a regular basis. You get your money's worth, plus the benefits of superior lubrication such as high temp protection, cold-flow capability and stronger oil film. Costs are only slightly more than dino oil at 5K changes (that includes oil sampling on synthetic, not on dino).



Vaughn

 

[amsoilman]

In my opinion, to justify the cost of Synthetic oil, the manufactors have come up with the idea of running it a longer time, thereby making it economically practicle. However, as I stated above, I have seen that lead to premature wear due to the filter plugging and circulating unfiltered oil through the motor... leading to abrasion wear.

What Steve says is true about changing filters, and that is exactly why Amsoil Inc. says to change oil filter at 6 month/12,500 miles using their 1 year/25,000 oils. They have been recommending this interval for 30 some years now! Now if you use a by-pass filter as well as a true syntheitic, and do oil analysis, the oil can and does last much much longer.



Wayne

amsoilman

 

[keimmmo]

Wayne,



I see you post a lot on the forums and I know you are highly respected! I believe Amsoil products are excellent quality. However, the first motor I tore down that had used synthetic oil and extended drain intervals was an Amsoil motor. That was about 15 years ago. The vehicle was about a 1976 Dodge van with a 360 motor. It had about 100,000 miles on it... the majority of that on Amsoil. Now in all fairness, the owner had NEVER done an oil analysis! The crank and bearings were WORE OUT from abraision wear!!! That 12,500 miles on a filter scares me to death!!! The oil is good! But, in my opinion, you need to change the filter A LOT more often!!!



If you don't plan to change the filter more often, at least do oil analysis more often. If you run under ideal conditions all the time (who does?) it might be fine. But I have seen what can happen when you go too far without changing the filter... and I sure don't want that to happen to my Cummins!!!



Again, no problem with the quality of the product you sell! You just have to keep the oil clean... in ANYTHING you drive and regardless of the brand of oil you use!



Steve