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Which oil brand to use?

21K views 49 replies 28 participants last post by  Broncowilly 
#1 ·
Hello everyone, new to the forum and I was wanting to pick everyone's brain on which brand of oil to use. I bought my first diesel truck (2014 Laramie Longhorn) and since it's used I will be doing the oil changes. I live in the south so 15W40 is definitely going to be the grade as well as synthetic but I'm having a hard time making up my mind on which brand to buy. Been looking at the Shell tella, my buddy uses Mobile 1 and I've been also looking at Royal Purple or Amsoil. Which do people preffer? your knowledge and experience is greatly appreciated. thanks
 
#44 ·
ROTELLA T6... In the truck and in my tractor. I used to use Valvoline Premium Blue Extreme religiously. But, did some reading and put the T6 in the tractor first. I could literally hear the difference. Really nice. And quite frankly, the price @ Slave_Mart can't be beat. NAPA has T6 and Premium Blue Ext for nearly the same price.
 
#45 ·
If the oil gets that bad/deteriorated that fresh oil makes a noticeable change in the engine's operation, does that mean that the OCI was too long and that the engine was getting damaged just before the change?


Synthetic oil is better for your car's engine and it improves your fuel economy. Myth. Steve Mazor, manager of the American Automobile Association's Research Center, says "I'm not sure it is worth the extra cost — you need to take some of the [manufacturer's] claims with a grain of salt." Blackstone's Stark says he has not seen data to support claims that synthetic oils boost increased fuel economy. "There is a school of thought that says the synthetic oils are slipperier and allow the engine to spin easier — I don't know that I believe that." Watch this short video for more on the ongoing debate over synthetic and conventional oil.
 
#46 ·
I agree with this also. Synthetic is not more slippery, it's better at extreme temps either cold or hot and it hold it vis over time better. As far as MPG, that's determined by the base oil vis. 5 -40 may give a little better than 15-40 dino. But I prefer the heavier oil between metal parts person opinion. Just my opinion. I think the slippery thing started by some saying synthetic is so slippery, you have to break in the engine before install it. IMO, that's not accurate
 
#48 ·
Glad I opened up this thread.

I rebuilt the engine in my truck and ran O'Reilly's house brand in it for 50 miles then dumped it and ran Rotella T synthetic. I noticed almost immediately the use of oil. I took the truck on a 1750 mile trip and went through three quarts! I dumped the Rotella T synthetic and switched to Delo 400 conventional oil. I just got back from a 2100 mile trip and used two quarts. I'm hoping I didn't glaze the cylinders :(

I've looked the turbo over real good and found nothing there that would suggest it's usage of oil.

I will be changing oil every 7500 miles on this truck. The cost is minimal for the piece of mind that having fresh oil in the truck brings :)
 
#50 ·
I certainly hope not. I know it runs great. I have a buddy who started off with synthetic oil on a brand new engine and he used oil like mad also. After switching to conventional oil it eventually cleared up the consumption issue. I'm hoping on the same :(
 
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