How long between oil changes with synthetic

[ROADWARRIOR]

I have always used Rotella 15W40 and changed every 3000 miles. Most trips are short, 15 miles or less. Some idle time and some pulling. I always changed it after 3000 miles for piece of mind. Well after seing the poor point of this oil, I switched to Rotella 5W40 synthetic. My question is, how long I can run this with out using an oil analysis. I figure if I can go 10,000 miles with a filter change at 5,000 miles I can make up the difference in cost. However, I don't feel comfortable going that long. It will take me 6 months or better to get that kind of mileage. What do you guys feel would be a safe change interval with plenty of safety margin figured in?



Thanks, Dan

 

[amsoilman]

Roadwarrior,

I would think you could go at least 2 times the normal recommended drain interval, but I would do an oil analysis at the recommended drain interval just to make sure the oil is still in suitable condition. Amsoil recommends a drain interval on their 5W-30 synthetic of 2 times or longer with oil analysis or 6 months.



On my own truck, (1994 4X4) I utilize the Amsoil by-pass system and their synthetic oil along with oil analysis every 10,000 miles, and I now have 135,000 with only one oil drain. Inside engine looks new. #ad

 

[DennyDay]

Oil

Oil is cheap, engines are expensive. I'd worry more about the 5w part than the interval. Cummins sez 6k miles average use, but they recomend 15w except in super cold areas.

 

[cullyguy]

The only way to know for sure is to have your oil analized. Don't guess! You will be surprised as to how well the synthetic will fair on extended drains. As you don't drive a bunch, pull a sample from the dipstick about 500 miles before you would normally change your oil. That way you will have ample time to do the change if necessary. In the end it boils down to : why guess with an engine that cost as much as ours

 

[Texas Diesel]

I'm sure that I am gonna get yelled at but here is my opinion.

Change, change, change that oil. Stay with a good dino lube and change the filter every time. Synthetics may be worth while for some but I have yet to see any data regarding dilution / contamination or sulfuric acid buildup being reduced in them. 450 filters in line with each other will reduce particulate accumulation but I have not seen a filter that can trap liquid contaminates. Many a good engine has gone 400,000 + miles on regular dino lube and maintanence + filter changes. No synthetic in the world is going to change the fact that you make short trips in freezing weather and no synthetic is gonna warm the oil enough to stop oil dilution by itself. I think you are 100% on track with what you are already doing. Keep up the good work. I'm not knocking them, I just think you are doing it right already.

 

[amsoilman]

TexasDiesel,

My last oil analysis indicated there was <0. 05 % water in my oil, and Total Acid was 3. 9. The oil I use will not become acidic as much because it starts out with a 12TBN when new. The (TBN) Total Base Number is a measure of the reserve capability of the oil to counteract(neutralize) acid formation from combustion by-products. TBN values will decrease over service life of a lubricant as it neutralizes acidic by-products. My TBN was reported as 7. 4



Wayne

 

[Archive]

Originally posted by amsoilman

TexasDiesel,

My last oil analysis indicated there was <0. 05 % water in my oil, and Total Acid was 3. 9. The oil I use will not become acidic as much because it starts out with a 12TBN when new. The (TBN) Total Base Number is a measure of the reserve capability of the oil to counteract(neutralize) acid formation from combustion by-products. TBN values will decrease over service life of a lubricant as it neutralizes acidic by-products. My TBN was reported as 7. 4



Wayne

Here is what I understand: blah, blah, blah, <0. 05% water in my truck, blah, my truck is on acid, blah, blah, 12 TBN ( Trinity Broadcasting Network) blah, blah, TBN decreases my oil's life, blah, blah.



Seriously, I would like to know more about this oil stuff. Where can I get more information so atleast I know what the words mean? Is there a chart or graph somewhere that does an apples to apples comparison between dinos and synthetics? Thanks

 

[ROADWARRIOR]

C. D. DAY,



Last year I had called Cummins about oil weight and they told me to use 15W40 year round. After reading about Rotellas pour point, I decided I would like to use their 10W40 synthetic blend. I called Cummins and again asked about oil, this time I talked to Mike and he told me that the 40 part has to stay the same, but that 10W, 5W, or 0W gets better the lower the number over the 15W.

I could be imagining things, but after switching to the synthetic, I swear that it takes less pedal to hold 65. I don't feel any other power improvements though.



On another note, will it hurt if I change to a synthetic blend for the summer. I mean that they always say to not switch oils around.



Thanks, Dan

 

[illflem]

Texas Diesel, try http://www.noria.com/ for all your oil and analysis questions. Their message boards are a excellent place to ask lubrication based questions, sorry TDR, but you will get much better answers than this site. There are lubrication and oil analysis professionals that hang out there.

 

[jwilliams3]

Not to be argumentative, but why would Cummins ship their engines with 15W40 if 5W or 10W (40) is superior?

Remember they are the manufacturer who designed, developed, and manufactures the great ISB and other fine Diesel Engines.

So why doubt their advice on oil grade?



I would keep changing oil and filter every 3000-5000 rather than keep some oil in my engine for an extended period of time.

Just my opinion.



"if it ain't broke, why fix it"

 

[amsoilman]

Texas_Diesel,

As Illflem said, go to the site for Noria oil analysis, http://www.noria.com/ and you will find out more about oil! In my last post to you, I was just stating FACTS! You didn't have to be smart about it



Best regards,



Wayne

 

[Vaughn MacKenzie]

jwilliams, there is no such thing as a non-synthetic 5W40 oil, and Cummins says no synthetics in a new engine.



For those who don't believe in synthetics, I say at least try it once. I could definitely tell an improvement in the sound of my engine and oil pressure & flow gets going quicker during those first seconds after startup.



I have run both Delvac 1 and Amsoil and like them both. I think the best of both worlds is a 5W40, better flow in cold weather yet has the 40 rating for operating temps. I really wish Amsoil would come up with a 5W40, I am running 5W30 now and will probably go back to 15W40 or back to Delvac 1.



I have been running 20,000 miles per change with a Stratapore filter every 7-8k. Oil results at 20,000 miles came back super, only 48ppm iron count, no water, fuel, or enough soot to register, viscosity/TBN in great shape.



Vaughn

 

[Jar Head]

Quote: "Not to be argumentative, but why would Cummins ship their engines with 15W40 if 5W or 10W (40) is superior?

Remember they are the manufacturer who designed, developed, and manufactures the great ISB and other fine Diesel Engines.

So why doubt their advice on oil grade?"



I'll tell you why... oil is expensive. Think of the thousands of gallons of oil Cummins has to buy to ship an engine. They're going to buy the cheapest oil they can. It's all about the dollar.



As to weight, Cummins has no idea where the engine is going to be shipped, so 15w40 is a good all-around oil to use. Once the engine becomes ours it is best to use a weight that is the most suited for the climate you live in. I think it is silly to keep using 15w40 just because that is the way the engine was shipped.



Another point to consider is that these engines are designed to be driven by idiots or the wife that hooks up a horse trailer turns the key and goes. We TDR members are a special breed. I shake my head in amazement the way some of you people maintain your vehicles - EXCESSIVE!



Personally, I use Delo 400 5w40 synthetic year-round (S. Ca. ) and I have yet to change it nor do I ever within the coming year and I can say with confidence (and no oil anaylisis) that I will never have an oil related failure.



As for you guys that use dino oil and change every 3000 miles, your engine will live forever.

 

[Cooker]

Chevron's Delo 5w40 is a non-synthetic oil, or maybe it is?



Chevron will market it as synthetic, but it is actually a Group III oil. Group III oils are not sythetic oils like the Delvac's One and the Amsoils (Group IV/V), but to the marketing world Group III classifies as a synthetic (Like Castrol Syntec).



Don't get me wrong, I think the Delo 5w40 is probably a great oil, but it is not in the same league of oils as Delvac One and Amsoil.



I guess the determination of wether the oil is synthetic or not is really up to how you want to classify a synthetic. For the majority of people "in the know" the Delo 5w40 doesn't qualify as a synthetic.



Check out this thread:

https://www.turbodieselregister.com/forums/showthread.php?s=&threadid=27328&highlight=Delo+5w40

Lee Weber as some good info on this topic.



My $. 02,

Ryan

 

[illflem]

That old thread has some misleading prices on the Delo 5-40 synthetic, many were quoting the price of 15-40 non syn. Chevron jobber dropped off two 6 ga cases of 5-40 at the farm today, it was $58. 62 per case delivered. I believe Amsoil is $70 per 4ga case. Going to give the Delo 5-40 a try in some of trucks and tractors this winter.

 

[C1B1DIESEL]

Here is a little some thing I found on a cummins page.



CAUTION

The use of a synthetic-base oil does not justify extended oil change intervals. Extended oil change intervals can decrease engine life due to factors such as corrosion, deposits, and wear.





If an engine is operated in ambient temperatures consistently below -23°C [-10°F], and there are no provisions to keep the engine warm when it is not in operation, use a synthetic CE/SF or higher API classification engine oil with adequate low-temperature properties, such as 5W-20 or 5W-30



just my . 02

 

[Cooker]

~$10 a gallon. I'd give it a try this winter too, that is if I could find somewhere to get it around here.

 

[JJW_ND]

I get to run my truck in months of below zero temps. I have experienced how much harder the engine is to start with dino 15W40 and how long it takes to get oil presure.



I also have seen how good 5W30 synthetic is with 20K miles on the same oil and 30 days of intown driving in temps below zero day and night.



If your daily drive includes regular temps below zero, you will really see a difference in 5W synthetic oils.



If you rarely see temps below 30 above 15W40 is fine.



The warmer the climate and the harder you drive the longer the change interval.



Even with straight 15W40 oil, hard pulling, cold winters I only changed at 6K. Sampled every change and never had one with even the slightest elevate soot, water, fuel dilution.



These engines run very clean.



jjw

ND

 

[jwilliams3]

"I'll tell you why... oil is expensive. Think of the thousands of gallons of oil Cummins has to buy to ship an engine. They're going to buy the cheapest oil they can. It's all about the dollar. "



Actually Jar Head,

Cummins doesnt use the cheapest lubricants available,

they are a top notch company that uses some pretty damned

expensive lubricants in assembly as well as operation.

 

[Texas Diesel]

Originally posted by amsoilman

Texas_Diesel, ...

You didn't have to be smart about it



Best regards,



Wayne

I didnt intend to sound like I was "being smart", I just didnt understand all the words. Sorry if I offended you. I will be following the iiflem sent, perhaps I'll learn something. Thanks