Forgive me, this is my first diesel.... I have always done oil changes every 3k-3500 miles on my gas trucks. I bought my LB7 used, and changed the oil first week. I used Rotella 15-40 and have gone almost 3500 miles so far. My mind is telling me to CHANGE IT and i have got conflicting info via internet about mileage intervals. What is the common safe mileage to change it? Is there a better oil out there to use? Thanks for your help!!!

my 04 book says to change it at 10,000 miles, I changed it every 5,000 miles since brand new with Rotella 15-40, truck uses no oil and has 278,000 miles and has the same oil pressure since new. Synthetic is probably better but changing it at 5,000 miles, I think makes up for the price difference between syn and reg oil. please , make out your signature so everyone that can help you knows what year your truck is and any modes to it. good luck with your first diesel===charlie

i usually change every 6,000miles but between 6 and 10,000 you should be ok with Rotella

i usually change every 6,000miles but between 6 and 10,000 you should be ok with Rotella
X2 every 6,000 for me!!

thanks for your opinions

I change mine at 5k miles, last time I didnt reset the oil life monitor and made it to 9,800 miles before the oil change notice came on...

Change every 5,000

Today's quality conventional oils (especially the big three; Delo, Delvac and Rotella) can clearly go 10k miles on oil changes, with "normal" use of the vehicle. (Normal being defined as anything that is not abnormal, such as fuel, oil or air contamination including air intake leaks, internal coolant leaks, excessive DPF regens, etc).

In other words, if your Dmax is operating properly, and you don't absolutely trash the engine, both the OLM and the UOA evidence show that 10k miles OCIs are very doable and anything less is a total waste of your money. There are, by now, dozens of UOAs on this site alone (and hundreds more at others like BITOG) that confirm this statement.

Any person is welcome to change their lubes as often as they see fit, but just because it makes them sleep "better" at night, that does NOT equate to taking "better" care of their vehicle; it only means they are comfortable with wasting their resources.

As alwasy, I would challenge anyone to put up evidence (facts and data; not rhetoric and hype) to disprove me.

7000-10K depending on how hard you drive. 7K is a good safe change interval with synthetic. You have to remember there is a lot more oil in there than on a gasser and less contamination.

I change mine every 7500 miles with Rotella 15w-40. 53,500 on the odo.

SP

7000-10K depending on how hard you drive. 7K is a good safe change interval with synthetic. You have to remember there is a lot more oil in there than on a gasser and less contamination.

Whoaa!! You must be rich!! (Just kidding) This is not meant to flame you in any way but just food for thought. If you are changing your synthetic every 7k and let's say you use any given Amsoil at around $8qt x 10qts=$80+$15 give or take for a good oil filter=$95+/- per oil change..by the time you have gone 40k you will have done 5 oil changes for a rough total of $475. I can buy a case of Mobil 1 Delvac 1300 15w40 (Non-synthetic) at Sam's Club(Walmart warehouse) for around $38 a case (4-1gallon bottles) x 3 cases=$114 which would be enough oil for the same 4 oil changes..$60 for 4 oil filters and I'm around $174. I go 10k per oil change so I'm actually making it to the same 40k for the money I've spent. Someone correct me if I'm wrong but I think my numbers are pretty much in the ballpark. Granted my Amsoil figures are based only upon their website prices and not from the standpoint of a discount from one of our vendors here. To each his own but I'm just trying to point out how you can stretch your $1 especially during these rough economic times and still get good protection for you truck. My Amsoil figures were in no way meant to slam them, as I have used some of their products, only to use them as an example of costs. (I use synthetic in all the toys in my signature.) Just my .02

Wow! I'm impressed, Madland. You actually looked at this from a logical point of view. Too many people here just "wing it" and/or fall into the barrel of "hype and mythology" when it comes to OCIs.

I agree with his assessment. Generally, synthetic oils cost about 3x - 4x as much money when you compare retail to retail, or sale to sale, prices. To get your money's worth, you have to extend your OCI 3x or 4x further, because you SURELY will not get 3x or 4x less wear from a synthetic for OCIs less than 10k miles. (There are simply too many UOAs out there to prove this, so it's not even up for debate any longer).

I buy Rotella synthetic that is much cheaper and a better oil in my opinion. I usually go 10K between oil changes, sometimes 15K. Peace of mind using quality oil, I rarely go past 10K, but I feel that I can. Oil contamination is something no oil can get away from though and if you drive your truck hard you will have it, and should change your oil earlier. I would rather waste money on good oil, then waste money on replacing and engine. My .02

Rotella 5w-40 synthetic 7500-10k miles with an Amsoil oil filter.

Whoaa!! You must be rich!! (Just kidding) This is not meant to flame you in any way ...I can buy a case of Mobil 1 Delvac 1300 15w40 (Non-synthetic) at Sam's Club(Walmart warehouse) for around $38 a case (4-1gallon bottles) x 3 cases=$114 which would be enough oil for the same 4 oil changes..$60 for 4 oil filters and I'm around $174. I go 10k per oil change so I'm actually making it to the same 40k for the money I've spent. ...(I use synthetic in all the toys in my signature.) Just my .02
Ok, first I will say that Madland, I agree with you 100%, if you’re not going to run the oil as it was designed it isn’t going to do anything for you.

Next I was going to stick on topic and say that for the first 4 years of owning my ’06 LBZ I ran AMSOIL 15W-40 to right at 20,000miles, and changed it, I would take an UOA at 10,000 miles and again at the time of the change just to build my confidence more than anything, and now I am changing the oil off of the UOA or for now I’m calling the run off at 40,000miles. And the only reason I’m going to call it there is I, m going to have to change the filter again then anyway, and the cost vs. reward just isn’t there, but I will sample it again and next time I may go for 60,000miles, but right now I’m at once a year oil change two filters and 4 UOA’s and right at $220 give or take a buck or two, so it’s the same distance for about $50 more than Dino, but it takes me less time and to me that is time I can be spending with my family or doing other things, so to me it’s worth it. And that $220 includes a the 10qt for the oil change, plus 5 quarts just in case and for makeup, and two filters, and 4 UOA kits.

Either way, if you’re going to use synthetics, to get the benefits you really have to push them past the old standard of 3.000miles, and even the new 10,000mile standard.

And I have no doubt that standard Dino is more than capable of at least 10,000 or 12,000miles without any trouble.

I bought 3 gallons of Rotella 5w-40 synthetic from my local Autozone for $15.99 each because the price on the shelf was marked wrong.:thumb:

bigman, I do agree, in pricipal, with your practices. It's good to see some members here actually use their noodle and analyze the facts and data, rather than just jump on the proverbial "synthetics are the best" bandwagon blindly. It's clear to me you truly thought through, and understand, your full maintenance plan.

Synthetics are great products that can give outstanding performance IF you understand how and why to use them. They are NOT a one-size-fits-all answer for every situation. They are part of a fiscal routine which can make sense if one approaches the ENTIRE maintenance program from a fiscal point of view, as you clearly are doing.

ANY FLUID HAS A FINITE LIFE CYCLE; SOME JUST LAST LONGER THAN OTHERS. If you match up your useage and maintenance plans, you'll do well in both protecting your equipment and your wallet. If not, you'll get burned one way or another, or perhaps both!

Whoaa!! You must be rich!! (Just kidding) This is not meant to flame you in any way but just food for thought. If you are changing your synthetic every 7k and let's say you use any given Amsoil at around $8qt x 10qts=$80+$15 give or take for a good oil filter=$95+/- per oil change..by the time you have gone 40k you will have done 5 oil changes for a rough total of $475. I can buy a case of Mobil 1 Delvac 1300 15w40 (Non-synthetic) at Sam's Club(Walmart warehouse) for around $38 a case (4-1gallon bottles) x 3 cases=$114 which would be enough oil for the same 4 oil changes..$60 for 4 oil filters and I'm around $174. I go 10k per oil change so I'm actually making it to the same 40k for the money I've spent. Someone correct me if I'm wrong but I think my numbers are pretty much in the ballpark. Granted my Amsoil figures are based only upon their website prices and not from the standpoint of a discount from one of our vendors here. To each his own but I'm just trying to point out how you can stretch your $1 especially during these rough economic times and still get good protection for you truck. My Amsoil figures were in no way meant to slam them, as I have used some of their products, only to use them as an example of costs. (I use synthetic in all the toys in my signature.) Just my .02

None taken, looking off the website those are retail prices- which many people pay instead of using a vendor and receiving a discount (for at least most of us I believe). Another thing in life where it is kind of a "get what you pay for" (not saying everything else is trash!!!).


Wow! I'm impressed, Madland. You actually looked at this from a logical point of view. Too many people here just "wing it" and/or fall into the barrel of "hype and mythology" when it comes to OCIs.

I agree with his assessment. Generally, synthetic oils cost about 3x - 4x as much money when you compare retail to retail, or sale to sale, prices. To get your money's worth, you have to extend your OCI 3x or 4x further, because you SURELY will not get 3x or 4x less wear from a synthetic for OCIs less than 10k miles. (There are simply too many UOAs out there to prove this, so it's not even up for debate any longer).

Generally agreed!

I change mine every 7500 miles with Rotella 15w-40. 53,500 on the odo.

SP
I also use the Rotella 15w-40 but change oil at 5000 miles. However, after reading these responses and other threads (thanks DNEWTON), I think I will push my changes up to 7500 miles. I also think that on this next oil change, at 7500, I will take a sample and send it off to see if my truck could possibly make it to 10K, that would be great! :thumb:

So for synthetics, go 40k and change the filter every 7-10k?

I would never suggest going 40k miles on any oil WITHOUT DOING UOAs ALONG THE WAY!

Extended oil drains can be very efficient, especially with quality synthetics and bypass filtration, but one should NEVER blindly go to such distances without verifying the condition of the oil as you progress through that mileage duration.

I know guys that have run more than 100k miles on one load of Amsoil oil and also use filter systems (including BP) and have great UOAs. But they also do UOAs every 10k miles to validate the continued use, and track their data to establish ranges and trends statistically. I even helped one guy write a program for his data. They also end up topping off the sump occasionally, and that (of course) helps bolster the add-pack.

The one "except for this ..." issue to not ignore is that of trucks which experience excessive regen cycles. They end up diluting the oil with fuel, and no oil/filter combination can take that for very long. This is one situation I'd say to stick with the OEM intervals. Even Amoil states 7.5k miles is the max here.

I think the point that most people are missing here is the "normal" folks can do right by their vehicle by simply sticking with "normal" fluids and "normal" OCI durations. There is no shame in that (it is what I do). But some folks are still stuck mentally in the "3 month/3k mile" mantra. The Dmax engine, paired up with today's quality dino oils, can EASILY go 7.5k miles, and typically will go 10k miles, with no ill effects. If you are to push far past that, then synthetics and UOAs are a must.

7000-10K depending on how hard you drive. 7K is a good safe change interval with synthetic. You have to remember there is a lot more oil in there than on a gasser and less contamination.

I change mine per the oil life monitor, which is in part dependant on "how hard you drive." The algorithm measures things like engine rpm, temperatures, and other information to determine how hard the oil has been used, and adjusts itself accordingly. Mine went 9900 miles last oil change, on about the same pace so far.

Since I only drive 12-15k miles a year, I use full synthetic oil. Probably overkill, but I'm only changing the oil every 9 months or so, so I don't mind spending the extra $8 or $10/gal for T6 Rotella.

Incidentially, what does your gasser's manual recommend. My last 4 gas vehicles have all had recommended change intervals of 5k miles or more. My 1500 Suburban goes 6500-7500 miles per the DIC. I think 3500 mile oil changes are based on an outdated practice carried on by those in the business of changing oil! Might be a hard habit to break, however!

I agree with dnewton3 100%, and I would never suggest going 40,000miles without UOAs either; I am only going that far because I use the UOAs.

I don’t really recommend going to 20,000miles without at least 1UOA at least somewhere in the middle of the run.

Even in the same vehicle with the same oil things change from run to run, and just because this run I am going to get to 40,000miles doesn’t mean that the next will net the same results.

And on the filter question, I run the EaO52 (in stock location) and after I got the results of my 20,000mile UOA back and was going to continue using the oil, I changed the filter only, so it was within the 25,000mile window that is claimed that it is good for. I didn’t cut this filter open, however, I have cut them in the past after a 20,000mile run and found nothing earth shattering, I can’t predict life left in the filter, but they were still passing oil, and not bypassing, so I called them good.

Also, I would recommend using a bypass filter setup to get the fullest life out of any oil, I have one, I just haven’t got it on, and it’s in the garage where it has been for 4.5years.

I also agree that there is nothing wrong with a normal oil change interval, and conventional oil, the only reason I run synthetics, AMSOIL for that matter, is because several years ago a friend of mine introduced me to it, he ran a long haul trucking company and that was what they used, and they were able to extend their oil life well past the recommended interval and extend their truck life past it’s expectation at the same time. I drive 40,000miles plus a year, and I figured it could save me a lot of time if I started using it, and it has. I have right at 190,000miles on my truck, and I have only changed the oil 8 times. Even at a 10,000mile oil change I would have had to change it 19 times with conventional oil, and if I had went ahead and fully trusted the UOAs from the beginning, I may have only changed the oil 4 times instead of 8 so over 4 years I have saved myself the hassle of changing the oil in my truck 11 times, the rest of my vehicles have been on the 1 a year to every 18month cycle, with UOAs and will be going to oil failure in the future, however, with my wife’s Equinox, oil failure comes earlier than it does in mine because of her driving habits, and environment. I drive mostly highway miles, and I drive 60 to 90min at a time; she drives 10 min to and from work, in stop and go traffic. But if I can get it to one oil change day a year and change all the fluids in all my vehicles and be done with it, I will be a happy man. I can pull an UOA sample in less than 5min and usually do it when I get home from work, and a filter change is also less than five min but I do that before leaving for work to minimize fluid loss, but the oil change, full fluid change usually takes me between 45min and 1.5 hours depending on vehicle and what is changing, and for me my time at home is very valuable I don’t get much time off and what I do get I don’t want to spend under my daily drivers.

Oh, and for me being able to order all the fluids and filters and have them delivered to my door, also saves me a trip to town, I stock up on trans filters and fuel filters when I get my Stanadyne, so there is no time lost to shopping either.

Every person and every vehicle is different, so what is best for you and your vehicle is ultimately up to you, so it’s best to do what feels right, just make sure to use the tools at your disposal to be sure the path you take is a solid one.

I change mine per the oil life monitor, which is in part dependant on "how hard you drive." The algorithm measures things like engine rpm, temperatures, and other information to determine how hard the oil has been used, and adjusts itself accordingly. Mine went 9900 miles last oil change, on about the same pace so far.

Since I only drive 12-15k miles a year, I use full synthetic oil. Probably overkill, but I'm only changing the oil every 9 months or so, so I don't mind spending the extra $8 or $10/gal for T6 Rotella.

Incidentially, what does your gasser's manual recommend. My last 4 gas vehicles have all had recommended change intervals of 5k miles or more. My 1500 Suburban goes 6500-7500 miles per the DIC. I think 3500 mile oil changes are based on an outdated practice carried on by those in the business of changing oil! Might be a hard habit to break, however!
My Ford F150 7700 series recommends 5000 miles between changes. I do mostly highway driving, over 150 miles per day. I few of my friends go 5k with there diesels and change just the filter, add a quart and run another 5k.

My next question is if one uses synthetic oil can you go back to regular or a blend? I have heard rumors that once you go synthetic, you can't go back?

Yes, many people do switch back and forth between the 2. I was doing that for a while, synthetic in the winter and regular in the summer for a few years. I extended my OCI and now just use synthetic all year round. In the past it may have been true, but now there is no problem going back and forth.

You can switch back and forth without an issue, you can even mix them if you want to.

I agree with dnewton3 100%, and I would never suggest going 40,000miles without UOAs either; I am only going that far because I use the UOAs.

I don’t really recommend going to 20,000miles without at least 1UOA at least somewhere in the middle of the run.

Even in the same vehicle with the same oil things change from run to run, and just because this run I am going to get to 40,000miles doesn’t mean that the next will net the same results.

And on the filter question, I run the EaO52 (in stock location) and after I got the results of my 20,000mile UOA back and was going to continue using the oil, I changed the filter only, so it was within the 25,000mile window that is claimed that it is good for. I didn’t cut this filter open, however, I have cut them in the past after a 20,000mile run and found nothing earth shattering, I can’t predict life left in the filter, but they were still passing oil, and not bypassing, so I called them good.

Also, I would recommend using a bypass filter setup to get the fullest life out of any oil, I have one, I just haven’t got it on, and it’s in the garage where it has been for 4.5years.

I also agree that there is nothing wrong with a normal oil change interval, and conventional oil, the only reason I run synthetics, AMSOIL for that matter, is because several years ago a friend of mine introduced me to it, he ran a long haul trucking company and that was what they used, and they were able to extend their oil life well past the recommended interval and extend their truck life past it’s expectation at the same time. I drive 40,000miles plus a year, and I figured it could save me a lot of time if I started using it, and it has. I have right at 190,000miles on my truck, and I have only changed the oil 8 times. Even at a 10,000mile oil change I would have had to change it 19 times with conventional oil, and if I had went ahead and fully trusted the UOAs from the beginning, I may have only changed the oil 4 times instead of 8 so over 4 years I have saved myself the hassle of changing the oil in my truck 11 times, the rest of my vehicles have been on the 1 a year to every 18month cycle, with UOAs and will be going to oil failure in the future, however, with my wife’s Equinox, oil failure comes earlier than it does in mine because of her driving habits, and environment. I drive mostly highway miles, and I drive 60 to 90min at a time; she drives 10 min to and from work, in stop and go traffic. But if I can get it to one oil change day a year and change all the fluids in all my vehicles and be done with it, I will be a happy man. I can pull an UOA sample in less than 5min and usually do it when I get home from work, and a filter change is also less than five min but I do that before leaving for work to minimize fluid loss, but the oil change, full fluid change usually takes me between 45min and 1.5 hours depending on vehicle and what is changing, and for me my time at home is very valuable I don’t get much time off and what I do get I don’t want to spend under my daily drivers.

Oh, and for me being able to order all the fluids and filters and have them delivered to my door, also saves me a trip to town, I stock up on trans filters and fuel filters when I get my Stanadyne, so there is no time lost to shopping either.

Every person and every vehicle is different, so what is best for you and your vehicle is ultimately up to you, so it’s best to do what feels right, just make sure to use the tools at your disposal to be sure the path you take is a solid one.

Excellent explanation- and a real life testimony. Very cool and thanks!

You can switch back and forth without an issue, you can even mix them if you want to.

Correct, however your extended intervals are cut down if chosen to do so (just as a heads up...).

I am about to change my oil at 30K miles. I did a UOA every 10K. I also run a bypass system.

IGO1320 - are you certain that you need an OCI? Have you sampled yet to determine that's necessary? Fumoto! I'd hope to see you get more than 30k miles out of a load of Amsoil, especially with a BP system in service.

I always enjoy seeing guys get really extended OCIs from their premium systems; that is exactly the correct use of those type set-ups. But at 30k miles, you're barely (if at all) breaking even on the costs.

Many guys that are serious about the extended OCIs use the live sample method and tailor their UOAs to the projected OCI plan.

10k miles = UOA
20K miles = UOA
30k miles = UOA
etc.

But as the UOAs tend to show some signs of caution, then will increase the UOA frequency to 5k miles. Eventually, they establish a safe range, and can adjust their OCI accordingly. Then, they go back to 10k miles after the OCI and back off one UOA cycle, knowing that it's likely a safe zone right under the "limit".