HOHN

...and it's only $23/gal for the API certified, diesel-rated 15w40.

Thought you'd like to know. I never understood why such a good oil wasn't more popular on this board.

jlh

Rare1

Delo 400 is $6.33 per gallon at Costco. Good enough oil.

joefarmer

The math doesn't add up for me. 3 gallons @ 23/gal = 69 +shipping. 3 gallons Delo 400 or Delvac 1300 @ $7/gal = 21 + $0 local pickup. I change every 3000 since the additive package is about used up, it's got .91% soot content and the oil has degraded viscosity to the next weight thinner (Delo 400, 3317mi, tested by OAI). Since I averaged 14995.3 miles last year, I changed 5 times. My concern is that RP would get too sooted on extended intervals even if the viscosity and additive package wasn't used up since it would need to run 10000 miles on it to break even. Am I even close on my reasoning?

brandon.

RowJ

There are two perfectly accepted ways to deal with oil changes, IMO. Higher quality synthetics...run for longer change intervals vs. less expensive oil changed more often.

I always figured that many members are so attentive to the maintenence of their trucks that changing more often is a "labor of love" - and a little less painful in the wallet at the time. I have seen national brands increase the quality of their oils a great deal over the last 10 years....closing the quality gap that use to exist. IMO, Delo 400 is an impressive oil for the cost. TBN has been raised to 12 and the additive package will easily hold up for 5,000 normal miles in a CTD.
In my business, we use to see a long term difference when higher quality oils were used. Cotton farmers, with JD tractors that needed overhauls at 8500 to 10,000 hrs, were getting 12,000+ hrs with better oil (not syntehtics...higher grade petroluem oils). A big factor in this was their not changing oil on time due to work loads or attitudes. I don't see this as much now-partly due to quality of engines...partly due to quality of national brand oils like Delo 400.

Brandon - With few...but hard miles, your reasoning makes sense. I do believe, however, that a superior Oil...like Royal Purple...will analyize as good at 10,000 miles as Delo 400 does at 5,000, under normal use.
You mention your viscosity getting thinner with wear. This seems wrong?? Used up oil usually oxidizes...getting thicker with wear (assuming your talking the viscosity # at 100* C). To get thinner would require something like fuel in the oil?
RJ

infidel

Keep in mind that there are a lot of reasons to change the oil. Oil oxidizes with time and temperature, oil gets contaminated with combustion byproducts, oil gets contaminted with soot from blowby, oil gets contaminated with fuel and water...particularily during cold starts, acids form in the oil, oil gets contaminted with dust/dirt/debris, the antiwear additive in the oil (the "zinc" or ZDP) gets depleted with engine revolutions, the anti-oxidants/anti-acids/detergents/dispesant additive deplete with time and engine revolutions.

Synthetic oil addresses the oxidation as it will handle higher temperatures but that is about the only advantage of synthetic, there is no way it can deal with contaimination...so...in short, using synthetic does NOTHING to allow a longer drain interval. Synthetic has the same amounts of ZDP, same problem with fuel and water contamination, same problems with other contaminates including soot, same problem with acid buildup, etc.... All reasons why synthetic oil does NOT allow longer drain intervals.

Forget the idea that synthetic allows longer drain intervals. It is hype by some of the synthetic marketers (primarily Amsoil) to sell/justify their expensive (highly profitable) product. They test under one set of best case conditions and then imply that that is the case for all conditions.

Flame away

Rare1

No flames Bill. You are exactly right.

If one must have $$$$syn and extended drain intervals, at least install a small-micron bypass filter. It will catch SOME of the contaminants Bill listed. Come to think of it, a bypass filter with Delo 400 is a good idea.

joefarmer

Here's the results in case I interpreted wrong:
1999 Dodge Ram 2500 Diesel, 177332mi, 3160mi on Chevron Delo 400 15W40

IRON 28
CHROMIUM 5
ALUMINUM 6
COPPER 3
LEAD 2
TIN 4
SILVER 0
NICKEL 0
SILICON 14
SODIUM 12
BORON 116
MAGNESIUM 18
CALCIUM 3396
BARIUM 0
PHOSPHORUS 1166
ZINC 1351
MOLYBDENUM 83
TITANIUM 0
VANADIUM 0
POSTASSIUM 0

Fuel <1% VOL
VIS @ 100C 12.53
Water 0% VOL
Soot 0.1% weight
GLYCOL NEG

TBN 10.55
OXID 22.0
NITR 20.0
F-SOOT 0.15

My remember function is getting bad as I get older. Soot was .1% instead of .9%. Any comments are greatly appreciated.

brandon.

infidel

Brandon, your silicon is a little higher than I like to see, what are you running for an airfilter?
Otherwise my feeling is you could safely double your change interval.

Rare1

Silicon should be about 3 for a 6000 to 7000 mile change interval. Your air filter stinks.

01redram

very interesting guys.i think i learned something today thanks

joefarmer

What? AFE Filters suck at sucking? I tried to convert to UNI filters, but they can't/won't make one for my application (5" inlet 6x16"). I'd run a prefilter, but I'm afraid of sucking it in. I was told that since the viscosity (12.57) was right at the next level (9.3-12.5 for 30wt) that I shouldn't run it more than 3500mi since it was basically worn out. How low can the TBN safely go?

brandon.

KennyL

IMHO all syn oils are better than conv oil. Air filtration is mostly shown in the silicon levels of oil analysis, and a good air filter is important. A low micron bypass oil filter should be added for any type of oil that you choose, This filters all of the oil and does not let any unfiltered oil to get to the engine.
I did some research on royal purple oil and there test results where obtained from a single cyclinder engine in a lab. This gives great head to head results against other oils but they dont tell you what brands they test against. They also dont give a full oil analysis report. It only shows better emision results, fuel savings, and power increases, It does not show in the report that it offers better protection then other oils.
The choice is up to you! With good maint practices any vehicle will give years of good service.

HOHN

Couple comments:

1) I found a cheaper place for RP oil-- www.longrider.com

2)Brandon, don't worry about the viscosity of your oil dropping into the 30 weight range. As long as you have no fuel or coolant dilution, I'd run it even if the viscosity got into the 9.5 range at 100º. Oil that's too thick is worse than oil that's too thin-- and oil tends to thicken as it ages and oxidizes.

3) Bill, you are right on. While I like synthetics (mostly for less cold thickening), newer dino oils are more and mroe impressive, at lower cost.

Consider the specs for Rotella 10w30. Pour point of -40! This, with a DINO oil. The Redline syn that I am partial to has a pour point of -49. Wow, 9 whole degrees by going from $7 gallon to $30/gallon.

4) Based on the owner's manual and other things I have read, I have concluded that 15w-40 is too thick for my application, and I will run 10w-30 (rotella or other) all the time now. I make a lot of short trips, meaning oil rarely gets up to temp. OM says 10w30 is fine year round. I'll trust the manual. If I towed, then the oil temp would make a 15-40 more appropriate, I think.

5) Rowland, Delo 400 is DERN good oil. Chevron has a good one, here. I'm trying to find a place to get the Delo in 10w30-- they do make it in that grade, don't they? I'd be curious as to the durability of a bypass/dino combo. I'm betting it's the cheapest path to incredible engine life.


6) All the stories I've seen of CTD lasting over a million miles are from guys that tow a lot and used dino. I'm concluding then that:
a) Hwy miles are easiest on the engine
b) The higher temps caused by towing actually HELP engine life, thinning the oil a bit and improving flow
c) Syn is really not needed for long engine life


I also find it interesting that I've read of how hotter engine bore temps reduce engine wear. I saw this graph that showed that bore wear decreased with hotter bore temps. I wonder if this has to do with tightening the piston clearance in the bore? I wonder if this has to do with the oil thinning at higher temps and actually improving lubrication?


I read that long oil article from another post, and it REALLY has me thinking about thinner lubes in general..


jlh

RowJ

Delo 400 starts with as TBN (Total Base Number) of 12. Most spectrometers (and industry recommendation) are set up to "flag" TBN when it gets to half the starting value....or 6 in Delo 400. 10.55 is about what I would expect at 3,000 miles on a diesel.
With no fuel, H2O or Glycol in your oil...I just don't understand the 30 wt viscosity # from a 15-40 wt oil??


HOHN - They do make Delo in a 10-30, but I do not believe they make it with a CI-4 diesel rating. They gear the additive package for street gassers only.


Infidel - "Forget the idea that synthetic allows longer drain intervals. It is hype by some of the synthetic marketers (primarily Amsoil) to sell/justify their expensive (highly profitable) product."

I think this statement is harsh, from my expirience, for the following reasons...
1- There are enough members out there doing regular oil analysis with Amsoil, Royal Purple, Redline, Hydrotex, etc on 10,000 to 15,000 miles oil changes to prove there is longer life to high grade oils. I'm not talking just synthetics.
2-Water, Fuel & Glycol contamination is pretty much a thing of the past...in todays tighter engines, and therefore, not usually a serious concern.
3-"Hard" TBN additives, used by higher grade oils deplete at a much slower rate and therefore last longer...but are more expensive.
4-There WILL be less soot formed when using a synthetic base oil...or, in the case of non synthetics, a Paraphenic vs a Napthenic base oil (used by most major oil companys). Synthetic and Parphenic base oils cost 2-3 time as much as the others and the base oil is 50-55% of the finished product we buy.
5-Thermal Stability of synthetics is a big plus for those looking to extend oil change intervals, as Infidel mentions, by making oxidation of oil almost a non factor for a lot of miles.

The one thing a higher grade oil can not deal with is Silicon intake. Get caught in a West Texas dust storm after just changing your Amsoil and you will probably should change it again.

As I stated earlier, I don't think the advantages of synthetics are what they use to be...10 yrs ago, because the major oil Co's have stepped up their quality. But, are synthetics just "Hype"? Not in my opinion. Will they last longer? Yes...but oil analysis is a must. Are they worth the extra cost with oil like Delo 400 and Delvac 1300 out there at $6-7 dollars a gallon? Your choice!
RJ