I am planning on changing over my 03 Duramax to sythetic oil. It has 5K miles on it and I just got the freebie LOF from the dealer so I think the next one will be due around end of summer, which I will have to do. I'd like to switch over to sythetic at that time (probably Amsoil). I know they have a 15w40 diesel oil which matches the factory viscosity but they also have a series 3000 with more protection. It is 5w30 (I think). Which would be a better oil for WI winters? Will the 15w40 be good enough or should I go with the series 3000 stuff?





Thanks

I run Mobil Delvac 1 5w40 year around. It does a fantastic job with our cold winters.

Ditto Delvac 1 year round ...





Mac

Mobil delvac 1 in winter and Amsoil 15w40 in the summer

Delvac 1 year round.

I went the full synthetic for the first year of the truck and to a 5w40 for the winters(Rotella). We had a cold one here in WI last winter, but I stayed with the 15w40. The cold oil pressures in our trucks is extremely high with the thicker stuff. On the real cold days 10 or lower the truck also struggles to turn over with it, but I never had a starting issue.


More than likely I'm going back to a 5w40 when it get's cold again though, it seemed to keep my mileage up a little bit running the thinner stuff as well.

Is the Mobil Delvac 5w40 the same as their Mobil one "truck and suv" that has the same viscosity? I saw some of that at Fleet Farm today but no Delvac.

The unofficial word is that Mobil 1 "Truck and SUV" is Delvac 5w-40 packaged in one quart containers.

Thanks k1xv, I thought it may be but wasn't sure. Now for the big question, I see most of you are using Mobil (delvac), why did you choose that over Amsoil or another?





Thanks

Actually, I am presently using Shell Rotella Synthetic 5w-40. I use that because it is available for under $13.00 per gallon at WalMart and is pretty good stuff, though some would argue that it is not really "synthetic". Until now, with it available as "Truck and SUV", Mobil 1 Delvac has always been a special order item and relatively expensive.


As for Amsoil, I have never used it, have no local source for it, and understand that some of its formulations have no SAE certifications because they were not submitted for testing or some other similar reason.


I will probably change over to Mobil 1 Truck and SUV when my present inventory of Shell Rotella Synthetic is depleted.

The 15w-40 Schaeffers 7000 motor oil is a blend and has a lower pour point than 10w oil.


I run it in my construction equipment only, since I don't keep my trucks long enough to get them broke-in.

Delvac 1 (aka Mobil 1 Truck and SUV) only comes in 5w40 -- makes choosing viscosity rather simple. http://www.dieselplace.com/forum/smileys/Big Smile.gif


I do wish it came in 15w50 (blow by may become a problem at some point w/ 5w40), but I don't require a heavier weight oil -- yet anyways...

The 15w-40 Schaeffers 7000 motor oil is a blend and has a lower pour point than 10w oil.


I run it in my construction equipment only, since I don't keep my trucks long enough to get them broke-in.





This is what I run in the winter. I would run it year round but I have free rotella so I use that in the summer. IL winters can get cold but not qute as bad as you guys. It does seem to flow better when the motor is cold than the rotella.

Do you have problems with the 5w30 (40) oils? That lower end is quite a bit lower than the 15w that they normally spec.

Not to go off topic, but this thread I just find funny.. It's not a bad question, it just struck me as funny.


Here it is, not even summer yet and we're talking about winter preps already. http://www.dieselplace.com/forum/smileys/Embarrased.gif


We just fret about our baby's too much at times. http://www.dieselplace.com/forum/smileys/Approve.gif


Anyway, back on topic.


I plan on Delvac 1 year around for the lower vis in the winter and the sightly improved heat transfer capability in the summer. Plus, it fits well with my planned yearly oil changes. (I don't pile miles on mine, maybe 10k a year max)

Well up here in the we don't get a long summer so have to be ready for the cold http://www.dieselplace.com/forum/smileys/Big Smile.gif. Actually the reason I was wondering was that I am not planning on doing the changeover to synthetic until late summer so need to have something that works well in the winter.

Delvac 1 year round. I've run my truck in everything from below zero to 110 degrees. No lubrication issues so far. Pressure is not too high in the winter nor too low in the summer. Like Goldilocks, it's just right.

TC

Your diesel supplement specifies 15-40 as the primary specification, with 5w-40 also approved (not 5w-30). In my location, depending on which way I am going, my first 5 to 8 miles from home are all down hill, so it takes time to warm the engine. I figure anything I might lose with 5w-40 year round when hot is more than offset by what I gain when cold.


And it does get cold here in winter. January 2004 seldom got above 0F, with an observed low of -23F. And we have not even hit 80F this Spring (yet), though when I venture out of this ice box I run into typical Northeast weather.


I have an 03, which has lower oil pressure than the 01 and 02. Using Shell Rotella Synthetic 5w-40, I never see less than 30 psi at idle when warm, and usually run 60 psi when warm.

You asked about the series 3000 Amsoil. I currently run Delvac after I got a funky oil analysis back on the 3000 stuff. The 15-40 amsoil is a great oil but in my experience the 5-30 is just too thin to run at the extended mileage that I can run delvac and the 15-40 Amsoil. The 3000 series oil sheered down to an even thinner viscocity and that raised a red flag to the oil analysis lab.


Every test with Delvac and the 15-40 Amsoil has come back great after 10K miles.

Can you elaborate on the weird results you got with the Series 3000? The Delvac has the same low end 5W and only has a little higher end when it is colder.

I run Delvac1 year round. I just changed my oil today and used 1-1/2 gallons of Delvac1 and topped it off with Mobile 1 truck and SUV. They are supposed to be the same thing but the Delvac1 was a darker color than the truck and SUV and they smelled different. Not sure about the taste. Just an observation. Edited by: Blue Max

Not sure about the taste. Just an observation.





Well break out the straw and report back to us, no half hearted reporting needed here http://www.dieselplace.com/forum/smileys/Confused.gif

Not sure about the taste. Just an observation.





Well break out the straw and report back to us, no half hearted reporting needed here http://www.dieselplace.com/forum/smileys/Confused.gif





http://www.dieselplace.com/forum/smileys/HiHi.gif

They both taste like chicken, who would have guessed?http://www.dieselplace.com/forum/smileys/Big Smile.gifhttp://www.dieselplace.com/forum/smileys/Big Smile.gif

Can you elaborate on the weird results you got with the Series 3000? The Delvac has the same low end 5W and only has a little higher end when it is colder.








with a 5w30 for example, first # is when cold, second number is when hot. Unless I am mixed up yet againhttp://www.dieselplace.com/forum/smileys/Embarrased.gif

ratlover,


(how come with a name like that you didn't get the 8.1L? http://www.dieselplace.com/forum/smileys/Wink.gif )


The colder the temp the more viscous a fluid gets and the warmer it gets the less viscous it gets. I'm not sure how these numbers translate to cP but with the 5w30 in hot weather it should not drop below a 5 and in cold it should not go over 30.





BTW how does that big V plow work on your truck? Is it too heavy for it?

Because I couldnt afford to feed a rodent that big with the miles I drivehttp://www.dieselplace.com/forum/smileys/Wink.gif Comes from the Chevelle boards I used to frequent before my current 2 door 69 project came to a screetching halthttp://www.dieselplace.com/forum/smileys/Cry.gif


The truck carrys it excellent! Timbrens in the front the proper amount of balast and she drops less than 1.5" with the blade up. No porpusing or anything wierd, drives like a champ up to the speed limiterhttp://www.dieselplace.com/forum/smileys/Shocked.gif I have a reg cab though. The blade has been great for the 1 season i have used it. The fishstik is kinda a PITA but supposedly they have redesigned it, I will probably be getting another controller because of that. DEATH TO THE MODE BUTTON!http://www.dieselplace.com/forum/smileys/Dead.gif anywho....


I know higher # = thicker. I know oil gets thinner as it warms and that was something that alwasy puzzled me, it realy didnt make sense. I thought the first # had to do with the cold. I know my schaffers I run in the winter dosnt have different oil pressure when warm than the rotela i run in the summer. Supposedly with its lower pour point even though it lists as a 15w 40 Schaffers specs put it closer to a 7-10w 40. It does act thinner when cold than the shell rotella.

Ya very true, the big blocks sure do suck down the gas, especially in the days of the quadrajets..


Thanks for the info about the plow, I have a 60" plow for my Polaris and that works OK but does not have the weight to move big piles of snow (and mud tires don't do well in snow either which prompted for the Sierra to pull it out a few times).


I'm guessing that even with the same viscosity that the synthetic will flow better when cold and be thicker when hot, than the conventional, so less affected on temperature.

Esso / Exxon 15w40 for summer


Chevron Delo 400 5w40 for Winter