How many are using this 5w40 in a warm climate? Would I be better off using a 15/40 like Amsoil? One more question, is 10,000 miles to soon to make the change ot syn oil?
Thanks

I'm running it in my truck here in Florida. I waited until 18k to switch over, many do it much sooner. I just completed a 500 mile round trip and averaged some respectable mpg's: DP MPG calculated at 16.5 mpg @ 60mph mostly highway speeds, some stop/go; 18.5 mpg at 70mph all interstate. :ro)

Of course the MBRP cool duals may have helped some to! Amsoil is good oil as well, can't go wrong with either one. I picked up the Mobil 1 Truck/SUV at Wally World for $4.88 a quart. Later. JJ :)

JJ,
Are you running the 5W40 and does walyworld have different weight oils in Mobil one? Also, is everything else synthetic in the truck as well?

The only Mobil 1 you want to run in a Duramax is Delvac 1 or Mobil 1 Truck & SUV. The others do not have the necessary CI-4 rating.

Mobil truck and suv here

Mobil 1 SUV here also. I just buy two 5qt containers for $19.88each @ Wally World and done!!!!

Ditto the comments on only using Delvac 1 or Mobil 1 Truck and SUV 5w40. Dang Wally World didn't have any 5 qt containers when I went in, could have saved me $10. :o:

Yes I'm running synthetics all around: Transynd in the tranny; GM synthetics in axle and differential; Mobil 1 engine. Later. JJ :)

Since you live in Houston, the 5-40W probably doesn't offer you any benefits over a good 15-40W, but you certainly won't go wrong with Delvac or T&S if you do decide to run that oil, at least IMO.

The Amsoil 15-40W is one of the only full synthetic oils in 15-40W that I know of.

I like to run 5-40W year round in diesels in my area because I may have to make a 30° start even in June sometimes.

I am actually just getting to my first oil change on my truck (BTW, that would be the 1000 mile first service), and I am going to go with Chevron Delo 400 15/40. I look at it this way, if the truckers feel that it's one of the better oils out, then it sould be good for me also.

I know many fleet truck companies who only use Delo 400, and are getting great life out of their motors. I have also decided that I am going to continue with my oil changes at 3000 intervals, just like I did on my cars. I also do not agree with what some I have seen here say about oil filter changes. They sould be done at EVERY oil change, not 15000 mile intervals as I have seen some here post.

Of course there are just my opinions on this matter.

John

That is definitely an excellent oil CBRJohn--my dad ran it in his 6.5 for ~150,000 with no complaints whatsoever. It has a proven track record.

And for what it's worth, I used to feel exactly the same way you did about changing oil. I'm changing my attitude now though--I'm aiming for 5,000 mile filter changes and oil changes every 10,000 miles, and this is still probably on the conservative side.

I'd say used oil analysis would probably help you determine a good drain interval and really save you some money in the long run over such short oil drains.

If using a good filter such as a Delco or Mobil1, is there need to change the filter at 5k, of just go all the way to 10k with it? I plan on doing 10k oil changes with Delvac1/T&SUV.

The guys over at Bobistheoilguy http://theoildrop.server101.com/cgi/ultimatebb.cgi? says the DMAX oiling system is good for 10,000 with the standard filter.

I just got 15 qts of Mobil 1 Truck & SUV for the truck. I still have 1400 miles to go until I make the shift and I will also be running 10,000 mile oil changes. I don't think I'm going for the 5k filter change unless I read a real compelling reason to. I've learned from industrial experience, that a human is terrible at knowing when the oil needs changed in something. Always want to do it too soon.

DavesDmax,

Quick check, may be just a typo, the Dmax only takes 10 qts of oil. Don't want you to overfill. JJ :)

Actually, JJ, mine takes 11.5 qts. I've done 5 oil changes and they all took 11.5 quarts in my engine.

I bought 3 5qt containers.

If my truck only took 10qts, I'd still buy 3 5qt containers.

Delvac 1 and Mobil SUV are the same thing just different bottle.

:wtf1: Every Duramax I've known has only taken 10 qts w/ filter change. You might want to check your dipstick. I know on the 01-02's they had the wrong tranny dipstick.

Actually, JJ, mine takes 11.5 qts. I've done 5 oil changes and they all took 11.5 quarts in my engine.

I bought 3 5qt containers.

If my truck only took 10qts, I'd still buy 3 5qt containers.

Thanks TxGuppy, I thought I had asked DavesDmax if he had an oil bypass filter on his truck to account for the additional oil. 10 quarts is what my owners manual calls for and also what my dealer, oil change place, and tire place always puts in my truck to. Always between the crosshairs on the ol dipstick. Wazzup? JJ :)

Delvac 1 and Mobil SUV are the same thing just different bottle.
Can you point me to some data to back this claim up. Not calling you a liar but I would like to know for sure if this is true...............;)

OD,

I researched this on the internet a couple weeks back and found where an analysis was done on the two and they were identical. I'll see if I can put my hands on that web site. This has been hashed out before. You might do a search on the forum as well. Later. JJ :)

OD,

I researched this on the internet a couple weeks back and found where an analysis was done on the two and they were identical. I'll see if I can put my hands on that web site. This has been hashed out before. You might do a search on the forum as well. Later. JJ :)
Thanks JJ it's been a busy month and I haven't been keeping up :). I see what I can find on the forum.

FWIW I pulled the spec sheets from the Mobil pages and they look identical on paper except the Delvac 1 meets SL and SJ (whatever they are) standards.

Thanks,
OD

Can you point me to some data to back this claim up. Not calling you a liar but I would like to know for sure if this is true...............;) Compare the "typical properties" spec sheet from Mobil on T & SUV

http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil_1_Truck_SUV_5W-40.asp

To the "typical properties" spec sheet from Mobil on Delvac 1

http://www.mobil.com/USA-English/Lubes/PDS/GLXXENCVLMOMobil_Delvac_1_5W-40.asp

They are the same. Yes, the Delvac 1 says it meets CI-4+, whereas the T & SUV only says CI-4, but I think this is mostly "badge engineering", similar to the differences between a Chevy and GMC Duramax http://www.dieselplace.com/forum/images/smilies/wink.gif

At the bobistheoilguy site, somebody actually ran oil analyses on virgin samples of both oils, and the only thing that looked different was the boron of the T & SUV was lower. However, oil specs and formulations are constantly changing and it was unclear as to the batch dates of each sample.

I am not saying things are the same today as years ago, but back around 1970 I worked for Esso/Exxon, and visited the lube oil plant. They were making motor oil in batches. You would not believe it....guys throwing a scoop of this and a bucket of that, into a big blending vat. based on the "recipe" of the oil they were blending.

OD, that's the study I read on bobstheoilguy.com . Dang memory! JJ :)

cfk2----yes you would be better off using amsoil 15-40--or for that matter amsoil has a 5-30 diesel hdd--excellant--10000 is just fine for changing the ground oil out to a real synthetic--you didn't need to wait that long!! the motor will continue to break in at it's own pace--just drive it. I use the hdd 5-30--year round-- the motor runs alittle cooler temp--it is also alittle quieter!!

good luck
Greg Carter Vermont

:wtf1: Every Duramax I've known has only taken 10 qts w/ filter change. You might want to check your dipstick. I know on the 01-02's they had the wrong tranny dipstick.
Yep, mine takes about 11.5 qts.

Guys on the board here have had anywhere from 10 to 12 qts with filter.

It's really not a big deal when you consider that even if it's only 10qts, that's still 2 1/2 gallons. Looking at the size of the sump, you're not going to notice any gain or loss in performance or foaming or suction loss in 10qts plus or minus 2.

Heck, put in only 8 and start it up. Then wait for an hour and see where you're at on the dipstick. You won't kill the engine.

Think about this, How low is too low to let the oil level get before you add?

For that matter, how high is too high before you starting foaming by the rods smacking into the oil? In automotive applications there's some of that going on most of the time anyway unless there is windage trays built into the sump. I think the Dmax does have some type of windage tray, but I'm not sure how tight it's built.

When I do my oil changes, I have the truck on ramps, on a sloped driveway to maximize the amount of oil drained. If I could stand the truck up on end to drain the oil, I would. (Too much effort to build the crane ):h ). When I fill it up I will add oil until I get to the full mark on the dipstick, (yes, it's the correct length). I do this on level ground with a saturated filter. It takes a while, but I'm usually beating the heck out of 12 qts.

Oh, and one other thing for you guys to ponder. If you could, what do you think the sump level would be if you measured it with the engine running and the oiling system filled. I think you would be surprised? :eek:


On our Emergency Diesel Generators at work, they have 500 gallon sumps and only needs to have a min of 150 gallons for operation. We only let them get down to 420 and our add mark is the same as a 55 gallon drum of Delo 400. Yep, it's over kill and by the same token, the reason we don't fill them higher is that there are sump inspection ports on the sides that would allow oil to run all over the floor if we had to take them off. Otherwise we would cram another 300 gallons in. These are Nuclear EDG's so we want to make sure that we they are needed to run, they will run a Long time before oil needs to be added. These are 2 stroke diesels and there designed oil consumption is our limiting factor, (about a gallon an hour), not what they really burn , (about a quart). We can also add oil on-the-fly, so they can run forever if we need them to.

I'm not a techie type so I'm totally unqualified to post any opinion on this. :rolleyes: But :D there must be a reason they put that statement in the owners manual, IIRC something about overfilling the crankcase can cause serious damage to your engine and may void your warranty. :confused: Every place that changes my oil to include the dealer, tire place, Jiffy, etc., puts exactly 10 quarts. :(

My question is how do you take 2 identical trucks with the same engine and oil pan and have up to a 2 quart variance filling the crankcase? Can it be that DavesDmax is getting more oil out of his crankcase by elevating it backwards? If that's the case for those of us only using 10 quarts we're leaving 2 dirty quarts in there to mix with the new oil? My oil is very clean after I change it, if it was mixing with old oil one would think it would turn dark quickly.

My truck will have been sitting for 24 hours when I get home today. I'm going to pull the dipstick to see where it's at. I bought 10qts Mobil 1 T&S, I'm anxious to see where the dipstick is. Once again I'm confused! JJ :)

JJ,

When I joined the board when the "Place" was started, every body was putting 11 qts in and LB7 engine. 1 qt for the filter and the rest in the sump. So, that would be about 11qts. Some were putting in a little more, some a little less, but it was around 11 qts. If they had some extra filtration, then they would add even more.

Now, you LLY guys are putting 10qts in total, OK, so what?

It's not a big deal to vary a little bit.

GM and others put in Nominal capacities in the manuals. Those are typical of calculated values.

They don't take into account on how much is drained, how much is left in, how soon after the engine is shut off, etc.

The manufacturers also put in nominal sump levels that will be OK for the average driver out there that buys their vehicle. Now, think about how much the average GM buyer knows about automotive technology. GM is covering their collective butt for the vast majority of typical uses that their vehicles will see. Those are the numbers that are in the owner's manual.

I notice that you use an Edge. You know of course, that GM doesen't approve of those devices yet, you still use them... Why doesn't GM sell them? Why do they work on some trucks and not others? Why do some people always seem to have problems with their trucks? Why do others never have problems with their trucks??

I want you to realize that since your not a "techie", as you call some of us, and that's OK, you have to know that if you use the information gained from other's expertise, you have to understand and accept the base responsibility and knowledge that comes with using that knowledge.

Instead of asking questions for instant gratification for some of these "simple" things like, "How much oil does MY truck hold and why is it different than someone else's?", Go out there and perform your own experiments. You might find out that I'm full of crap or, that Your truck is indeed a little different.

People tend to learn more by experiencing the event themselves rather than reading about it.

I'm sorry, I don't mean to lecture but please don't act naive about why some things don't make sense to what you read or have been told. We're all big guys and girls on here and I think that we are all smart enough to Trust but verify the information giving to us.

And, as always, your mileage may be different. ;)

"Now, you LLY guys are putting 10qts in total, OK, so what?"

DavesDMax, it sounds like you have an LB7, sorry my mistake. I thought we were talking LLY's. I thought I asked a very direct, succinct question that on the face would appear easy to answer. :o: I didn't realize the LB7 engine body and oil pans were different than the LLY's, so a 1-2 quart variance is apparently normal/acceptable. Sorry! :)

BTW, when I use the "techie" term I hope the boyz know that is just my way of recognizing their technical expertise with these trucks. Never meant it in a derogatory manner. Obviously you took offense to my asking about your methods, sorry again! :rolleyes: OK, that's 2 sorry's, JJ's all out! Down to business! :D

As for your statement "Instead of asking questions for instant gratification for some of these "simple" things like, "How much oil does MY truck hold and why is it different than someone else's?", ... bad assumption dude. I do receive gratification when I learn something that will help me to protect my truck, operate it safely, and get the most life out of it. You stated something that appeared to me could void your engine warranty, others like myself were reading it to, it deserved to be called. This is why I initially posted directly to you that the 11.5 quart figure sounded kind of high and might hurt your engine. That wasn't criticism, just a friendly heads-up. Evidently my bad! :confused:

So other LLY owners, how much oil are you putting in your trucks when you change the oil. I pulled my LLY owners manual when I got home to verify oil capacity (10qts including filter) and also see if I was recalling that statement correctly about not overfilling the crankcase. Here it is verbatum: Notice: Do not add too much oil. If your engine has so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, your engine could be damaged. I also checked my oil level and it was right at the top of the cross-hatched area-excellent! I have no idea what happens when you overfill, but there must be a good reason for GM to tell us not to. Anyone out there know why? :o:

This is a good post, good intel is being provided that should be beneficial to other LLY owners. I learn more when we open these discussions up. Sometimes we inadvertently step on toes, very common with e-mail formats like this to lose the true context/demeanor of a post, but usually at the end of the day we all learn something.;) I for one really appreciate those that post, yes DavesDmax included, since it is much easier to sit on the sidelines and not offer an opinion or advice for fear of getting flamed. :o: Not ol' JJ, too much money in this truck for me to do something stupid to it. I have learned a lot on the DP, still learning! :ro) I didn't know what Edge Juice, MBRP, WI, ... was until I joined the DP forum. Thanks!:exactly: Later. JJ :)

ON EDIT: DavesDMax, I just saw that mpg jab! Cheap shot! ):h

JJ,

Again, I'm sorry. I didn't mean for the response to be flame like or that your questions were bad. I don't like to just give an answer to a question without putting some logical perspective on the situation. That way, anyone who reads it, has enough background to perform a gut check to see if it makes sense to them.

I never meant to get sucked in to the details of LLY ownership as there may be some tangible differences between the 2 engines that I might inadvertently give out bum dope to someone who may not know any better. I was just commenting on the oil thing. It really is a good price if you don't need the "CI4+" rating of the NEW Delvac 1 formulation. As far as I know, none of the Dmax's require a CI4+ rated oil...

Also, I don't think there is any difference in sump level between the LB7 and LLY. But there could be.

I also don't have a "cross-hatch" area on my dipstick. I assume the LLY has the same style of "cable and Potted cast metal at the end". I didn't recall seeing any posts where LLY guys were discussing changes in the dipstick. As it is, I can not comment on why the LLY manual says what it says because I don't have that statement in the LB7 manual.

But I do recommend that you double check to make sure you're not reading the standard diatribe for gasser stuff. GM has that buried everywhere.

No offense on the use of the term "techie".

I just wanted to convey some calm that no ill will befall your engine if you're not perfect in refilling the oil. There is no way the you, I, or anyone else, including GM, could ever control all of the variables that cause oil to move around in an engine. The Dmax is put in a vehicle that moves. A truck is not stationary so the fluids are influenced by the same forces that you are when the truck is in motion. Therefore, there is going to be a fudge factor, (nice technical term eh?), in what GM will recommend as an acceptable level. I also wanted to give out some practical exercises to allow all to think about what goes on inside of an engine and come to a rational understanding of why something is, the way it is. It's certainly not magic, and more often than not, the specs called for are just convenient for the manufacturer.

I asked a Westinghouse design Engineer why he spec'd a certain size bearing for a mission critical pump, expecting to hear a good sound engineering judgment reason.

His answer was, "Because we had those on the shelf. Be glad the ones on the shelf were not twice as big!"

Just something to think about when pondering the 10qt question.

I hope you understand my statements JJ. That's all I was ever trying to say. No ill will or malice at all. I don't play those games.

Nuff said DavesDmax! ;) Since we've apparently already answered the Mobil T&SUV oil question hopefully we're not hijacking this thread by continuing this discussion. If so the original poster should advise. :)

FWIW I did check the owners manual, then the little supplement they give us for the Duramax. It has that same statement in both about not overfilling the crankcase. :confused:

I had put some thought to the fact the vehicle is moving, parked on inclines/declines, etc., and that the fluid is moving when the vehicle is. Coupled with the oil expanding/contracting due to viscosity changes maybe it could interfere with crankcase ventilation which could cause some damage? :confused: This may be the very reason they caution against overfill. Is there a need to have sufficient free space in the crankcase to avoid vacuum lock or something similar? :confused: I know, I'm way out on a limb here! :o:

On edit I may have found the answer to this question. Unlike the LB7 the LLY's crankcase ventilation runs to the intake so the hot oil fumes/gases are combusted again versus how the LB7's are just vented to the atmosphere. If we overfill the LLY's do we run the risk of drawing straight oil into the intake, that doesn't sound good! From there I'm not sure what would happen: can the engine combust oil?; would it clog injectors?; could it drain the crankcase? Full of questions! Need answers. :D

Someone out there has to know the answer! Where ya at dude or dudette (politically correct):h )? Good discussion! JJ :)

I don't want to get in the middle of anything here, and this reading is all very good information, but I wanted to say that my truck also takes approximately 11-12 quarts of oil.

After the oil has been drained and I am ready to put a new oil filter and oil in, I don't fill the oil filter before I install it (which I should probably do). Anyway, I first put in 10 quarts, put the cap back on and drive it around to let the oil circulate within the engine. I then let the truck sit for approximately 15 minutes and check the oil level. I then have to add another quart to get it to the full mark. Then typically, I drive the truck for a week and check the oil again and add another quart to get it to the full mark.

It seemed extremely odd when I first noticed this on my new truck, but I have now dealt with it as the way it's going to be and I'm not going to try to change it. Whatever the truck wants is what I will do. My only logic for using this much oil is because there are alot of nooks and crannies (including the oil filter) for oil to occupy and it takes awhile for the oil to be distributed to all of these differents places.

Dan

StraitDiesel, that's what the forum is for, to put intel out there for all to digest. Is your truck an LB7 or LLY, 2004 had em both? Any type of oil bypass in use? JJ :)

My truck is an LB7, no oil bypass system, completely stock except for edge/attitude.

Dan

It would be so much easier if you LB7 guys would just go ahead and trade up to an LLY to avoid any confusion on the LLY forum! ):h Your experience is identical to DaveDmax then. Evidently something changed with the LLY going to crankcase ventilation to the intake which altered crankcase capacity.

I had my oil changed last Friday, took a 500 mile round trip on Saturday/Sunday, let the truck sit overnight yesterday, checked the dipstick and it is right at the top of the crosshairs, er marks whatever they call em. ):h

Hmm, if I go to a GM parts site and order the oil pan for a LB7 and an LLY and they have different numbers, BINGO! Standby!

On edit, finding the oil pans for the LB7 and LLY is proving more time consuming than I thought. Anyone else have fast access to the part numbers? JJ :)

It's a mistake to minimize the differences between the Truck & SUV and the Delvac 1. That 75% increase in boron alone makes them different, which is consistent with what other refiners have stated about the characteristics of CI-4 Plus oil. The boron based additives are expensive--designed with soot control and longer drain intervals in mind. More boron doesn't necessarily mean better mind you, as too much can be harmful as too little in some formulations could be harmful.

Trucks with catalytic converters will particularly benefit from CI-4 PLUS oil. It's expensive and it's YOUR truck. You will have to decide if the expense is worth it in the long haul.

Probably what needs to be done here is a few rounds of simultaneous virgin tests of the Delvac 1 vs. the Truck & SUV to see if the boron and/or other components are still different. They should be or else there should be a great outcry from Mack Trucks and the fleet owners who have chosen the more expensive route (in initial cost) of motor oil supplies.

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=11;t=000202#000000

Ask and you shall receive. I found this last night on bobstheoilguy's site. The majority concensus seems to be the 2 are one and the same. There are a couple of threads on that site about the two. And I thought I was anal, that forum is full of "Super Duper Anal" boyz. Looks like ol' JJ is going to have to join yet another site. Last_Z knows dis sh_t! :ro) JJ :)

I E-mailed mobile oil sometime back and mobile 1 truck and suv is what they said to use. I switched at 3000 mi. No problems here. I can't stand the thought of going 10,000 miles between oil changes, guess I'm not a believer. I change every 5000...................Rick..... p.s heard the mobile 0ne oil filter p/n M1-303 is the best one to use.