Help me choose a oil

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Mar 17, 2022
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15
So I bought a 25 GMC 2500 with a 6.6 Duramax and its been 15 years since I had a diesel and things have changed.
I'm getting close to 10000 miles so time for another oil change on me. I will probably always do 5000 mile intervals even tho I believe full synthetic is the way to go. The dealer uses Mobil Delvac super which is syn blend but they will do the oil change with whatever I bring in.
I've narrowed it down to 3 but I cant tell if one is better than the other.
Mobil 1 Delvac Extreme
Chevron Delo XSP
Shell Rotella T6
The one thing I noticed about the Chevron says they reduce soot levels which is awesome for a truck not deleted. Can a oil really do that?
Am I dwelling too much on this or is there a big difference between the three?
Thanks
 
So I bought a 25 GMC 2500 with a 6.6 Duramax and its been 15 years since I had a diesel and things have changed.
I'm getting close to 10000 miles so time for another oil change on me. I will probably always do 5000 mile intervals even tho I believe full synthetic is the way to go. The dealer uses Mobil Delvac super which is syn blend but they will do the oil change with whatever I bring in.
I've narrowed it down to 3 but I cant tell if one is better than the other.
Mobil 1 Delvac Extreme
Chevron Delo XSP
Shell Rotella T6
The one thing I noticed about the Chevron says they reduce soot levels which is awesome for a truck not deleted. Can a oil really do that?
Am I dwelling too much on this or is there a big difference between the three?
Thanks
Any of those are good oils but I'll add that Mobil seems to offer rebates even during good economic times. Whereas SOPUS has not been great on HDEO oils. I used to be nothing but Rotella buyer for their rebates but about 5 yrs or so back they just sort of stopped offering competitive rebates or none at all for long periods. I believe Chevron to be even worse for rebates from my experience. This may not be an issue for you however.
 
Ash from oil consumption is the concern addressed by lube oil choice, not soot.

In a truck that new, if I planned to keep it a long time and wanted to get as much DPF life as possible, I'd run Delo ADF 600. It's a mature oil. Now available at walmart, two rebate cycles a year, etc.

Oh wait, that IS what I'm doing...despite my truck not being nearly that new.

If not, I'd run Delo 15w-40 or Delvac ESP 5w-40, capitalize on the rebates, and move on in life. Both have had good rebates in recent history.

EDIT: What is your climate in terms of winter temperatures? I assume 15w-40 is appropriate?
 
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Delo ADF 600. It is almost ashless and was developed to increase the length between big diesel truck DPF removals for cleaning.
Everything indicates it was super well tested and works great for commercial fleets.
NAPA carries it, though you may have to ask a local store to order it. They're good about ordering for you though.
 
I'm in East Tn so we have maybe 15 days a year it gets below freezing
Then ADF 600 being only available in 10w-30 and 15w-40 is not a barrier for you.

O'Reilly (with coupon) or Walmart are your best pricing, and then stock up if chevron runs future rebates.

Unless you don't figure the reduction in sulphated ash (0.4%) vs a more typical CK-4 oil (1.0%) are worthwhile, or you are really bent on a "full synthetic" base (ADF 600 is "only" a blend), in which case there are other options.
 
Thanks for all your comments and suggestions and the winner is Mobil Delvac Extreme. My selection is probably based on cost but it does not mean I wouldnt switch to Valvoline or Chevron if a deal came up. With 5000 mile OC I dont believe ash should be a huge problem with Delvac . Dont thrash me over cost since I bought a 89000 dollar truck but I can get Delvac extreme at BJ's 35% cheaper than the ADF 600 from Walmart. Thanks again
 
With 5000 mile OC I dont believe ash should be a huge problem...
OCI is irrelevant when considering ash accumulation in the DPF...unless somehow there's a supported theory that says oil consumption is greater at the end of an interval than at the beginning.

In the long run, using a good oil that keeps the engine healthy (and thus, not consuming oil past the rings or ccv blowby) protects the dpf as much as using an oil that minimizes ash accumulation when it does get burned.

Delvac Extreme is not a bad oil. $90 pails at walmart and a $40 rebate are enticing. $10/gal after rebate vs $15/gal after rebate for the ADF, to each their own.
 
Thanks for all your comments and suggestions and the winner is Mobil Delvac Extreme. My selection is probably based on cost but it does not mean I wouldnt switch to Valvoline or Chevron if a deal came up. With 5000 mile OC I dont believe ash should be a huge problem with Delvac . Dont thrash me over cost since I bought a 89000 dollar truck but I can get Delvac extreme at BJ's 35% cheaper than the ADF 600 from Walmart. Thanks again
SuperTech 15W/40 full synthetic is the least expensive of the ones recommended in this thread.
 
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