Oil for new 6.7 High Output

Thank you to all who have responded - and to those who have yet to respond. Quite the education.

I had not heard of Triax Lubricants before but will be looking into them ASAP. (I tend to be OCD too.)

Although my original question was more about why both Ford and O'Rielly showed the Motorcraft 5W-40 Synthetic as not "fitting" the 2025 F-250 High Output Diesel, given the experiences shared here, I'm good with accepting the idea that the websites just haven't been updated yet - and that all of the oils mentioned so far are more than adequate for a new 6.7 High Output Diesel engine.
Not meaning to double post but there was requests for Triax update across multiple threads.
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Well having been a Rotella T6 guy for as long as I can remember I was skeptical but willing to experiment a bit ….. I’m OCD on oil analysis because of my marine mechanical background. Marine engines run at virtually full load all the time under way because of constant water friction against the hull as opposed to us 4 wheel jockeys where the load reduces once the truck is rolling! For those of you that know this just ignore my tendency to over explain.

So I took my brand new F350 6.7 HO and went with the Triax 5w-40 Fleet Supreme at 1066 miles replacing the factory build oil and sent that out for analysis with Lake Speed OA. My analysis came back with what was determined to be “Typical” initial first change results. The Silicon and Copper ppm numbers were slightly elevated as expected on the factory first fill oil.

My plan is to change again the next three times at 4000 mile intervals hopefully establishing a stabilized baseline trend pattern and then moving to 5000 or 6000 mile increments monitoring total and individual wear metals contamination.

I have an Insane Diesel Bypass Oil Filter kit for this truck sitting in the garage waiting. Any thoughts from you oil geeks on when I should install it, or if I should I can’t decide because I want to evaluate its effectiveness as well. To do that engine break-in must be completed so I’m thinking as soon as my OA comes back stabilized over two periods….. what say you?

I’ll keep posting my OA sheets as I go along. also this is a daily driver (30% local, 70% Highway with infrequent 8,000 Lb Trailer Towing).
 
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Rotella t6 5w40 can't go wrong with that. i even use Riotella in my motorcycles.
 
Like I posted earlier, I have used Triax now for years and every UOA that I have is great. The new formulations of Triax HDDO, specifically 5w40, has shown to be damn good.

I just put their GL-5 75w-140 in my diff so we will see how that goes. On their spec sheet for the gear oil the VI is 199 which would only be that high with a majority percentage of PAO base so I am quite pleased there.

At this point you can call me a Triax fanboy as I even put their oil in my Can Am quads. Hell, I'd probably drink the stuff at this point. All joking aside, once Mobil went to the new CK4 and their Delvac 1 ESP 5w40 formulation changed up pretty significantly from the CJ4 I went to Valvoline PBE which also had really good UOA's. If I had to list my oil by pref it would be Triax 5w40, Valvoline PBE 5w40, Amsoil Sig 5w40 and Mobil Delvac 1 ESP in 0w40 if I could get it.
 
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I just put their GL-5 75w-140 in my diff so we will see how that goes. On their spec sheet for the gear oil the VI is 199 which would only be that high with a majority percentage of PAO base so I am quite pleased there.
Very curious to see how you like the GL-5.

I’ve been using Triax 5w40 FS now for the last 2 oil changes (truck has just under 15k) and I’ve become a fan of Triax products. So much so that I’ve switched our other two vehicles over to Triax. My wife’s ‘17 Yukon with the 5.3 has had a noticeable “tick” sound at idle since driving it off the showroom floor. Dealer said it was normal. Had ran Mobil 1 0w20 since new. Switched to Triax Synergy 0w20 15k ago and the noise has been gone. Haven’t heard it since. Their detergent package seems excellent. Vehicle has 115k on it now and I see myself staying with Triax for the foreseeable future.
 
Where do you guys buy the TRIAX oil? Do any local shops sell it or are you just doing mail order / Amazon?
 
Like I posted earlier, I have used Triax now for years and every UOA that I have is great. The new formulations of Triax HDDO, specifically 5w40, has shown to be damn good.

I just put their GL-5 75w-140 in my diff so we will see how that goes. On their spec sheet for the gear oil the VI is 199 which would only be that high with a majority percentage of PAO base so I am quite pleased there.

At this point you can call me a Triax fanboy as I even put their oil in my Can Am quads. Hell, I'd probably drink the stuff at this point. All joking aside, once Mobil went to the new CK4 and their Delvac 1 ESP 5w40 formulation changed up pretty significantly from the CJ4 I went to Valvoline PBE which also had really good UOA's. If I had to list my oil by pref it would be Triax 5w40, Valvoline PBE 5w40, Amsoil Sig 5w40 and Mobil Delvac 1 ESP in 0w40 if I could get it.
I wasn't aware that it recently changed when was that, was that before or after I did the virgin sample? I need to do my front and rear diff services as well, just lazy but I am at 60k miles but mostly easy highway driving but it is almost 5 years old (original diff oil).

Very curious to see how you like the GL-5.

I’ve been using Triax 5w40 FS now for the last 2 oil changes (truck has just under 15k) and I’ve become a fan of Triax products. So much so that I’ve switched our other two vehicles over to Triax. My wife’s ‘17 Yukon with the 5.3 has had a noticeable “tick” sound at idle since driving it off the showroom floor. Dealer said it was normal. Had ran Mobil 1 0w20 since new. Switched to Triax Synergy 0w20 15k ago and the noise has been gone. Haven’t heard it since. Their detergent package seems excellent. Vehicle has 115k on it now and I see myself staying with Triax for the foreseeable future.
I've been doing this in my wifes jeep wrangler JLU with the 2.0t. Using Triax SRT oil that is recommended for those vehicles where lowspeed ignition could occur. I also have used the FS-HDDO from leftover jugs in my push mower when I needed to change it out.
Where do you guys buy the TRIAX oil? Do any local shops sell it or are you just doing mail order / Amazon?
I've gone direct and or amazon, just depends who has the gallon jugs I need.

At this point just waiting to see reviews on the PPE oil filter and that might be my next purchase, until then using the revised FoMoCo filters at roughly 10k mi OC intervals since the labs support going even farther (I just change it when the oil life minder alerts me).
 
The gear oil was reformulated about a year ago I believe. The HDDO was reformulated a few months ago I believe.

I'll be doing the rear diff this weekend and depending on how it performs after, I'll probably do the front diff towards the middle of September. As for the t-case, I am going back and forth on that one and have not decided. Once Banks comes out with their pan for the 10R140, I'll do the transmission and see how the Triax does there.
 
The gear oil was reformulated about a year ago I believe. The HDDO was reformulated a few months ago I believe.

I'll be doing the rear diff this weekend and depending on how it performs after, I'll probably do the front diff towards the middle of September. As for the t-case, I am going back and forth on that one and have not decided. Once Banks comes out with their pan for the 10R140, I'll do the transmission and see how the Triax does there.
Well shit I bought some 5-40 fs a while back no idea if I have the old stuff or new stuff you’re talkin about is it a big deal or no ?
 
The gear oil was reformulated about a year ago I believe. The HDDO was reformulated a few months ago I believe.

I'll be doing the rear diff this weekend and depending on how it performs after, I'll probably do the front diff towards the middle of September. As for the t-case, I am going back and forth on that one and have not decided. Once Banks comes out with their pan for the 10R140, I'll do the transmission and see how the Triax does there.
hmmm I wonder if there is literature out there about the change, i didnt really see anything on their website but did a quick check. Keep us updated on the rear diff. I doubt there is a drastic change but I am curious; if it's anything like their HDDO it should be good. Do they make an ULV trans fluid?! That's where i have always been scared and just used FoMoCo stuff.
Well shit I bought some 5-40 fs a while back no idea if I have the old stuff or new stuff you’re talkin about is it a big deal or no ?
my sample of virgin oil was from 03/2025 but the jugs were purchased a 4-8wks in advance easy as I saw the oil life getting low, (that 10% prep warning or whatever it is the prealert from FordPass). I am wondering if it is different myself.
 
Well shit I bought some 5-40 fs a while back no idea if I have the old stuff or new stuff you’re talkin about is it a big deal or no ?
Honestly, it wouldn't be something that would cause me not to run what I'd already purchased. Even their old formulation was great oil and high percentage Group IV (PAO) base. Now that I think of it, I want to say the HDDO reformulation was around 12/24 to 1/25. But since @gmbpilot757 has an email into them, we'll know soon enough.
 
I'm now interested in this Triax. Anyone have a VOA from Rotella or MC 5w40?
My old MC UOA shows higher zinc, phos, mag and calcium numbers than the Triax VOA. The Amsoil UOA does as well.
Not trying to make this an oil thread fight. Just want to compare apples to apples.
 
Triax is definitely peaking my interest. I wonder if it would be beneficial to make the switch from T6?
 
I'm now interested in this Triax. Anyone have a VOA from Rotella or MC 5w40?
My old MC UOA shows higher zinc, phos, mag and calcium numbers than the Triax VOA. The Amsoil UOA does as well.
Not trying to make this an oil thread fight. Just want to compare apples to apples.
i dont think anyones looking to fight here about it, numbers are numbers including dollars, there might be better oils out there with more in the package but might be more cost prohibitive (i don't physically mean not affordable) just that the extra cost for the add'l stuff may not be worth it. Throw up the VOA and lets get a badass repository going.

Just a quick google puts this in the following for amsoil (granted cheaper or more expensive also doesn't always mean better/worse):
  1. amsoil max duty at $57.39/gal
  2. amsoil heavy duty at $39.19/gal
  3. a gal of triax FS at $32.49/gal
I don't know if i would want to continue to spend almost $230 for oil lol if my UOA is going to come back and show the same wear as Triax. I can't say I've ever used Amsoil though, but I do know Triax quieted down my 6.0s a lot, helped prolong injectors, one could argue reverse stiction, and fought sheer wear and tear beatdown from the HPOP that it was good enough for me to consider going forward into my 6.7.

With that being said, someone showed some crazy back to back flawless no wear score from Amsoil, i'd probably jump ship tomorrow and swim on over to the Amsoil boat.
 
i dont think anyones looking to fight here about it, numbers are numbers including dollars, there might be better oils out there with more in the package but might be more cost prohibitive (i don't physically mean not affordable) just that the extra cost for the add'l stuff may not be worth it. Throw up the VOA and lets get a badass repository going.

Just a quick google puts this in the following for amsoil (granted cheaper or more expensive also doesn't always mean better/worse):
  1. amsoil max duty at $57.39/gal
  2. amsoil heavy duty at $39.19/gal
  3. a gal of triax FS at $32.49/gal
I don't know if i would want to continue to spend almost $230 for oil lol if my UOA is going to come back and show the same wear as Triax. I can't say I've ever used Amsoil though, but I do know Triax quieted down my 6.0s a lot, helped prolong injectors, one could argue reverse stiction, and fought sheer wear and tear beatdown from the HPOP that it was good enough for me to consider going forward into my 6.7.

With that being said, someone showed some crazy back to back flawless no wear score from Amsoil, i'd probably jump ship tomorrow and swim on over to the Amsoil boat.
I used amsoil for years and it is great oil but imo the price is just out of control it’s just a matter of principle for me lol
 
i dont think anyones looking to fight here about it, numbers are numbers including dollars, there might be better oils out there with more in the package but might be more cost prohibitive (i don't physically mean not affordable) just that the extra cost for the add'l stuff may not be worth it. Throw up the VOA and lets get a badass repository going.

Just a quick google puts this in the following for amsoil (granted cheaper or more expensive also doesn't always mean better/worse):
  1. amsoil max duty at $57.39/gal
  2. amsoil heavy duty at $39.19/gal
  3. a gal of triax FS at $32.49/gal
I don't know if i would want to continue to spend almost $230 for oil lol if my UOA is going to come back and show the same wear as Triax. I can't say I've ever used Amsoil though, but I do know Triax quieted down my 6.0s a lot, helped prolong injectors, one could argue reverse stiction, and fought sheer wear and tear beatdown from the HPOP that it was good enough for me to consider going forward into my 6.7.

With that being said, someone showed some crazy back to back flawless no wear score from Amsoil, i'd probably jump ship tomorrow and swim on over to the Amsoil boat.
I'll dig up what I have and post it.
Ine thing to note; the Amsoil Sig Series is the $57 one. Amsoil HDDO is the $39 one. The HDDO is $29/gal if you have the PC. While the PC membership is an added cost, if you have multiple vehicles it adds pennies per quart of oil. For comparison sake with just diesel oil, I would just use the retail cost sans PC.
While they were a long time sponsor, I'm not a rabid Amsoil freak. Genuinely interested in options for these trucks.
 
I'll dig up what I have and post it.
Ine thing to note; the Amsoil Sig Series is the $57 one. Amsoil HDDO is the $39 one. The HDDO is $29/gal if you have the PC. While the PC membership is an added cost, if you have multiple vehicles it adds pennies per quart of oil. For comparison sake with just diesel oil, I would just use the retail cost sans PC.
While they were a long time sponsor, I'm not a rabid Amsoil freak. Genuinely interested in options for these trucks.
Ok I give you guys keep saying HDDO what the hell is that
 
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