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Preferred choice of oil

I run Delvac and for the first time, ran a Mobil 1 filter. I then too it off after 1000 miles and replaced it with the AC Delco. The Mobil 1 didn't do a great job of sealing up no matter what I did. Lots of drips in the gargage. As soon as I switched to AC Delco the dripping completely stopped.
 
The best filters for the price are Baldwins.

The Donaldson endurance line are great filters also. The mobil filter isn't that great it's still a 35- 40 micron filter. Why even bother with the fram, mobil, and others on the shelf filters when there are much better filters on the market for nearly the same price. Filtering is more important than the oil you use.

X2 thats all we use.
 
I use Amsoil oil and the filter bypass and I would bet ya that my motor is better off than those who run stock filters, the filters are the life blood and the by pass filter down toa couple of microns I think....someone will chime in on the real deal
 
Tim the amsoil systems filter down to 1 micron. Filters are more important than the product you dump in it, but you have thebest of both worlds.
 
Switched to Mobil 1 5W40 for my last change - easy to find (NAPA had it) and really not that much of a price difference compared to dino oil. The main reason I switched was for cold weather starts. Figured it might help with fuel economy on short trips which I do quite a bit of - but still would have switch regardless of fuel economy for the cold weather starting. It pours noticably easier at normal temps than 15w40 so I believe it will make a noticable difference in cold weather - will know this Winter. I'll stick with the DIC to guide change frequency but will run it closer to the end of the cycle, had been changing at oil life 25%.
 
Switched to Mobil 1 5W40 for my last change - easy to find (NAPA had it) and really not that much of a price difference compared to dino oil. The main reason I switched was for cold weather starts. Figured it might help with fuel economy on short trips which I do quite a bit of - but still would have switch regardless of fuel economy for the cold weather starting. It pours noticably easier at normal temps than 15w40 so I believe it will make a noticable difference in cold weather - will know this Winter. I'll stick with the DIC to guide change frequency but will run it closer to the end of the cycle, had been changing at oil life 25%.

No DIC in 6.5, we are ancient.
 
Ok so I am going to add to this. I am about to do a change in mine. I am thinking of trying the Mobil 1. I have been using the Amsoil. I like the amsoil I am tight on money and I can save a $20 but its 5w-40 and I have been using the 15w-40. Its currently 112* and I am not sure about the 5w........ any advice?
 
Keep in mind that the second number of an oil's viscosity grade (40 in this case) is the steady weight of the oil when at 100 degrees C (212 degrees F) and it compares with any other 40 weight grade oil, in thickness, regardless whether it's a 5W-40 or 15W-40. This is a (ASTM D-445) standard test which must be passed to be called a particular viscosity grade oil.


Mobile 1 Turbo Diesel Truck 5w-40 properties sheet (Mobile 1 Spec Sheet)show viscosity and high temperature shear numbers as:

Kinematic Viscosity cSt @ 100ºC: 14.9

Kinematic Viscosity cSt @ 40ºC: 100.4


Viscosity Index, ASTM D 2270: 155

HTHS Viscosity, mPa•s @ 150ºC ASTM D 4683: 3.9




Assuming you are currently using AME 15w-40 Amsoil, viscosity and high temp shear numbers are:

Kinematic Viscosity @ 100°C, cSt (ASTM D-445): 14.2

Kinematic Viscosity @ 40°C, cSt (ASTM D-445): 93.2

Viscosity Index (ASTM D-2270): 157

High Temperature/High Shear Viscosity: (ASTM D-4683 @ 150°C, 1.0 X 106 s.-1, cP): 4.3



Without getting into excruciating detail about the derivation and numerical shift over service life of these numbers, suffice it to say the 5w-40 will work just fine in your application.

You are losing some high temp shear protection and are giving up a fair amount of drain extension capability due to M1 TBN of 10.7mg KOH/g vs. Amsoil TBN of 12.1mg KOH/g. Total Base Number (TBN) is the ability of a lubricant to neutralize acids formed by combustion, the higher the number, the more acid it can effectively combat.

Overall, the M1 will not last as long as the Amsoil before it shears down in viscosity and/or is depleted of acid neutralization capability (TBN), only you can decide if it's worth the $.

Hope this helps, let me know if I can be of further assistance.
 
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Synthetics are superior, without question. Once you use it in your engine you can never go back to the conventional oils or you will have problems.

What? I've heard this over and over and never believed it. Someone would have to show a scientific report showing this for me to believe it. How does the engine know whether it is syn or not? And what kind of problems will it cause?

I tried the Rotella syn. 5-40 for a while. Truck ran fine. Used 2 quarts between changes and I change every 5000k. I switched to Mobil 1300 15-40 and truck runs fine. Still change at same intervals and still uses 2 quarts between changes. I found no difference yet.

The winter may tell a different story as the syn is thinner starting out but still retains the same properties when hot.
 
Synthetics are superior, without question. Once you use it in your engine you can never go back to the conventional oils or you will have problems.


This is just plain false.

What? I've heard this over and over and never believed it. Someone would have to show a scientific report showing this for me to believe it. How does the engine know whether it is syn or not? And what kind of problems will it cause?

I have never, nor do I expect to see, any actual evidence of this.
 
If you gave me a free Fram filter I would not use it. I have cut way too many oil filters apart in the last 20 years to even consider using one. No matter what Fram says or advertises - seeing is believing. I use Wix filters religiously on my vehicles. I use the factory Mack filters on the big truck. I recently cut a few K&N oil filters apart in the dyno room and they are high quality as well. Delco filters are/were? made by Wix but it seems that the quality has dropped on them recently, probably a request by the General to save money.

I agree completely on the Fram standard filters. Total trash.

Try cutting a Fram HP4 apart. I think you'll see it is different - much more robust - and priced accordingly. They cost like 10 bucks.

-Rob :)
 
Except for a couple of changes, I've always used Delvac 1300 in the Dmax running 5K intervals. I'm too anal to get the main benefit from synthetic because I wouldn't be able to resist draining the stuff out at 5k. Approaching 65,000 miles as of yesterday.


...and I just realized another thing- this is the longest I've kept any vehicle to date!
 
Except for a couple of changes, I've always used Delvac 1300 in the Dmax running 5K intervals. I'm too anal to get the main benefit from synthetic because I wouldn't be able to resist draining the stuff out at 5k. Approaching 65,000 miles as of yesterday.


...and I just realized another thing- this is the longest I've kept any vehicle to date!

Taking an oil sample and having it analyzed is much cheaper and provides a ton of information about engine health. Food for thought.
 
I actually had 3 of them done when the truck had between 20-25k on the clock from what I remember... one each with Rotella Syn, Delo 400 (not the LE- it wasn't out yet) and Delvac 1300S. They all looked excellent at 5k intervals oil wise. Ended up sticking with Delvac because the truck seemed to burn about 2qts of the Rotella Syn, but not the others.

I'll have a Blackstone report done on the current oil when I go to change it and will also see if I can find the old ones to post.
 
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