Well, it took almost 10 months to get it, but here are the numbers. I did an oil analysis with AVLube at apx. 5k, 10k and 15k miles on Delvac1. I had NO make-up oil before the 10k sample was taken. After the 10k sample was taken I added about 2 1/2 quarts of make-up oil. This was a combination of oil consumed and oil taken at sampling. At each sampling I removed about 8 oz. of oil (4oz. for the sample and 4oz. to keep in case I wanted to retest it later for particle count.)

Each sample was taken using an oil thief through the dipstick tube. Things to note:
*The Virgin Oil numbers reflect a range based on three virgin samples found here and on bobistheoilguy.com threads. There is a range because of lab and batch differences.
* I am using an Oilguard bypass. It's claim is a guaranteed doubling of OCI. Since the Duramax says change the oil at 10k miles, I should be able to go atleast 20k miles.
* The claim of the Oilguard is 3 micron absolute/ 1 micron nominal in a single pass. My analysis numbers DO NOT give ANY indication of this claim. This is because a "ferrographic" oil analysis is needed in order to prove this. These cost about $100 each and not in my budget. The purpose of this post is to show how my oil fared over 15k miles using the Oilguard and basic spectrographic oil analysis (about $20 each).

test........ Virgin..... 5323mi..... 9859mi..... 14810mi
...................WEAR METALS
Iron........ 2..... 7..... 11..... 18
Chromium 0...... 0..... 0..... 0
Lead....... 0..... 5..... 6..... 13
Copper.... 0..... 11... 15.... 21
Tin......... 0...... 0..... 2..... 4
Aluminum. 1...... 2..... 2..... 3
Nickel...... 0...... 0..... 0..... 1
Silver....... 0...... 0..... 0.... 0
..................CONTAMINANTS
Silicon.... 4-7..... 7..... 9.... 12
Boron...... 39..... 50... 40... 40
Sodium... 0-1...... 2.... 1..... 2
Potassium.. 0..... 14... 11.... 15
...................ADDITIVES
Magnesium 444-488........... 472... 343... 479
Calcium... 2023-2513....... 2229... 1896... 2126
Phosphorus 994-1257...... 1476... 1203... 1409
Zinc....... 1204-1368....... 1589... 1327... 1602
...................OTHERS
Nitration........10..............7.........8...... ...8
Oxidation........15.............14........14...... .14
Visc100..........14.6...........13.4....13.6...... 13.6
TBN................11.2-12......10.3....10.1......10.13
soot................<0.1...........<0.1......1.1*....<0.1

Some noteables.....As long as all other variables are consistent, an oil is considered good as long as the TBN stays above 1/2 of new. So Delvac1 is good to about 6 or so. At 15k it is still 10.13.
The additives are still at virtually "new oil" levels.
The make-up oil added is reflected in the "additives" rise between 10k and 15k samples.
There is a consistent steady rise in contaminant and wear metal numbers. This is because no oil filter or bypass has the ability to filter sub-micron contaminants. Therefore, sub-micron wear metals and contaminants will continue to increase in concentration until the oil is completely flushed. However, because these components are in the sub-micron range, there is no harm by having them in the oil.

Ultimately I like knowing that I am 1)Saving time 2)Saving money 3)Not wasting perfectly good oil by changing every 5k 4)Getting my money's worth out of exceptional yet expensive oil 5)Running oil through my engine that is probably CLEANER and less abrasive than most oil at 2-3k miles even when mine is at 15-20k miles!!! A full flow filter simply CANNOT keep the abrasives down when it is limited to 25-30 micron filtration.

A big thanks to AVLube for helping me with understanding my oil analysis. SPICER

Good info Spicer! Looks about like what I get @ 7500 mile intervals with Delvac 1300. What is your total capacity with the Oilguard (mine's somewhere between 11-1/2 to 12 quarts.)

Josh

Excellent info. Arlen. That oil is really holding up well. Couple of guestions.

Did you run both filters the full 15K?
Will you continue to run the oil further?
Those numbers are excellent and the pattern falls in perfectly with your explanation. Outstanding!

Good info Spicer! Looks about like what I get @ 7500 mile intervals with Delvac 1300. What is your total capacity with the Oilguard (mine's somewhere between 11-1/2 to 12 quarts.)

Josh
Yep, about the same.

Also I did not mention,.... I changed the filters last night. The oil looks so good I don't see the point in changing it. But I was REALLY curious to see the condition of the Oilguard filkter element. After dabbing it down with a rag it looked 100% fine. Then I used a box cutter and sliced the element open from top to bottom. The element looks litterally like a BIG spool (like a thread spool) wound with 1-2mm thick cotton yarn. The yarn itself is wound apx. 1 3/4 inches thick. I sliced it from top to bottom. There is enough cotton yarn in this thing to make a small mop ! The middle of the "spool" is a steel cylinder with perforations to let the clean oil through. The top and bottom are epoxied and sealed to the first (top and bottom) layer of yarn. I saw no significant build-up of soot on the element. I must admit, though, the stuff this filter is designed to filter is WAY beyond the human eye's ability to see.

Also of note: the high soot on sample 2 (10k) was most likely an error, confirmed by the lab. Soot does not go from 0 to 1.1 to 0 again.

SPICER

Excellent info. Arlen. That oil is really holding up well. Couple of guestions.

Did you run both filters the full 15K?
Will you continue to run the oil further?
Those numbers are excellent and the pattern falls in perfectly with your explanation. Outstanding!
Yes, both filters to 15k. The full flow was an Amsoil. I plan to use the new Oilguard full flow in the future. It is made by Champion labs abd has a rating within 1 micron of the Mobil1 and is a full synthetic fiber. (Mobil1 is also made by Champion Lab). For now I threw on a Baldwin I had left over.

Yes, the oil will stay in. Filters changed out last night as explained above.

Strangely, after swapping out the filters and adding about 1 1/2 qts. make-up oil and running for 15 minutes, the oil looks really clean again. Oilguard does not claim to make the oil "clean looking". A black oil can be pristine and a clear oil can be filthy. As quoted by Oilguard, the dark color remaining in the oil is from the "dyeing effect the carbon ash has on the oil molecules". When the oil is put on a rag it actually looks much clearer than when on the dipstick. I drive fire trucks for a living. Now THAT is some BLACK OIL!!!! SPICER

So what exactly does the oilguard do?

Would one see these numbers without one?

Would change intervals be shorter without one?

Thanks
Ben

So what exactly does the oilguard do?

Would one see these numbers without one?

Would change intervals be shorter without one?

Thanks
Ben
The Oilguard is a "supplement" filter to the regular oil filter. You still have a regular oil filter. The bypass filter takes a small amount of oil (about 1 quart per minute at road speeds/rpm's) and runs it through a super fine filter media. A typical oil filter will trap particles ABOVE 25-30 microns in size ( a human hair is about 100 microns wide). The bypass filters down to 1 micron. The tollerances in our engine are down to about 5-10 microns. The most damaging particle size is the 5-10 micron size because these particles can get between the tight spaces and cause wear.

As you drive, you are constantly filtering the oil to 1 micron. Every 10 minutes or so theoretically all of your oil has passed through the bypass.

We change our oil every 5,000 miles or so NOT because the oil is "worn out", but because it is contaminated with soot, dirt, byproducts of combustion, wear metal and other things that can cause wear to the engine. A standard filter can NEVER filter to 1 micron because it would be too restrictive(starve the engine of oil). By using a bypass, the engine uses the standard filter to supply the engine with oil and the bypass to supply the sump with super clean oil.

Would you see these numbers without one? I honestly don't know. Possibly. HOWEVER, as I mentioned above the standard spectrographic oil analysis used in this case (the $20 variety) CANNOT tell you the concentration of harmful particles in the 5-10 micron range. It is limited strictly to ppm concentration. In order to test for particle concentration one must do a ferrographic oil analysis. These are the $100 variety and not what I want to spend my money on. One may run their oil for 15k like I did using a standard oil filter and get good numbers, but the oil could be full of shards and abbrasives so it is not advised.

Oil like Delvac1 has been documented to go as many as 100,000 miles on an oil change using bypass filtration! This stuff does NOT wear out! It DOES get dirty and abrasive from contaminants. A bypass gets rid of this contamination so that the oil may continue to perform. To the engine the oil is still "good as new".

So that answers your last question "would change intervals be shorter without one?" Yes. Not because the oil is no good. The oil is still PERFECTLY GOOD. It is just too dirty and abrasive to be kept in the engine safely.

If you want more details. go to www.oilguard.com (http://www.oilguard.com). The website has a ton of really good info, FAQ's, and REAL data that is helpful. The hardest part of this unit is installing it. The concept is VERY simple, but as far as I know they do not sell a custom bracket for the Dmax. I made a template for a custom bracket and had our Fire Dept. mechanic weld it up for me. It is bolted to the frame and is SWEEEET! I am not a mechanic and fear things like this, but it really wasn't all that bad, just took some time. SPICER

Awesome looking tests. Delvac 1 rocks ! :ro) :ro) :ro)

I have a friend who works for Harvard Corporation as a field rep. He has numerous testimonials from trucking companies that use periodic oil analysis w/Harvard filters and run over a million miles w/o an oil change. This is getting easier to do because the electronics on the engines keeps from overfueling the engines, which puts alot of soot in the oil and dilutes it with fuel.

So Spicer do you have any pics of the oilguard in place? Sounds like it is the bomb! After reading your reply, it sounds very impressive.
What kind of bracket did you make?

Ben

So Spicer do you have any pics of the oilguard in place? Sounds like it is the bomb! After reading your reply, it sounds very impressive.
What kind of bracket did you make?

Ben

I will have to post some pictures. It is 3/8 inch thick steel plate cut and welded into a bracket. Our truck frame is not flat on the inside, so I also welded 1/2 inck thick "washers/spacers" on the back to allow it to mount flat over the bulge in the frame. It is right behind the main oil filter and is bolted to the truck frame through 3 factory holes in the frame. (I did have to drill the holes a little wider). I also primed and painted the bracket to give it a stock look and keep it frpm rusting.

Many others have mounted it to the floor of the truck right under the drivers feet. SPICER