Powerstroke

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I recently changed over to Rotella T6 after 8,000 miles on stock Motorcraft and Delo oil in my new 7.3 Powerstroke. I swear that the engine is quieter and seems to rev more quickly. Am I just imagining things?
 
It's possible. Engines respond to different oils in a variety of ways. Sounds like T6 might be a good match for your motor.
 
Normally I would say "you're imagining things," the power of suggestion is really, really strong and when you change a fluid you tend to expect a change that 99.99% of the time isn't there.

HOWEVER- a 7.3 Powersmoke is different since the oil also fires the injectors. If the high pressure oil pump and the rest of the HEUI system work a little differently with the new oil, it can directly affect things like the injection profile, which certainly CAN change diesel combustion sounds. So its not as likely to be all in your head as it would be if this were a gasoline engine or a diesel with either common-rail or mechanical injection.
 
Originally Posted By: matt711
I recently changed over to Rotella T6 after 8,000 miles on stock Motorcraft and Delo oil in my new 7.3 Powerstroke. I swear that the engine is quieter and seems to rev more quickly. Am I just imagining things?


Possibly quieter. But rev more quickly?
 
I'll ask a few rhetorical questions, and you mull over the answers ...

1) How does one accurately judge "noise" percieved at the human ear? Did you use any SPLM (sound pressure/level meter) or or other auditory calibrated device?
2) How does one accurately judge the rate of revving? One would need to be able to definitively develope a relationship between the accel pedal and the rate of vehicle movement (or revving in park) if accurate measurements were to be taken.
3) HEUI gets blamed for so much stuff; it's tiresome. Did you know that in a 7.3L PSD, the HPOP oil only lifts the pintle for the injection event, and a spring closes it? (As opposed to the 6.0L PSD, which uses oil for both open and close cycles). So, would the oil only get 1/2 credit or 1/2 blame in a 7.3L PSD?
4) You indicate this is a "new" 7.3L; how much experience do you have with this engine family, and this one unit in particular? Do you have a decent basis to make subjective observations?


Originally Posted By: matt711
I swear that the engine is quieter and seems to rev more quickly. Am I just imagining things?

Probably so. To prove it, you'd need a whole slew of accurate, dedicated equipment.

Or, the alternative would be to run a large series of trials back-to-back (30 or more), running short OCIs with both fluids, letting a trusted friend do your OCIs in a blind test and then note your "observations"; you'd need at least a 95% confidence level of correct assignment to make it believeable.

I don't doubt that you perceive it to be so, but that does not make it a reality. You may well be correct, but to convince me, you'd have to prove it, not just claim it. And I have serious doubts you'd have to overcome to change my mind.

I know I take the fun out of things, but I'm just "that guy" who relys on facts and data rather than subjective mythology.
 
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Typo... 6.7 not 7.3. It's a 2013 F250. Not sure what I was thinking when I typed that.

I definitley did not use any scientific methods just seat of the pants. As some have suggested my own subconcious need to feel like spending the money on full synthetic may be overpowering my objectivity. I guess I will have to just to enjoy my ignorant bliss and keep telling myself that the engine is really liking the new oil...

Can't speak to any starting issues in the cold. Im in North Carolina and it has not been below 90 degrees is a long time. Loving the truck though. MPG has been amazing for a truck this size.
 
Good to know.

Obviously the HEUI is a non-issue.

Cold starts will never be an issue in NC.

Why not consider 10w-30 HDEO? You'll see a slight liberation in fuel economy. And your engine is spec'd for it.
 
I guess I fell into the "synthetic" trap.... Only a few dollars more and all that. If my MPG goes down I will probably switch back.
 
The Ford 6.7 has an engine driven (not HEUI) pump for raising fuel pressure for the injectors (like the CR Duramax or Cummins)-you'll get quicker unaided cold starts in cold weather with 5W40, but a 10W30 like Rotella T5 would be an excellent choice too.
 
Originally Posted By: bullwinkle
... -you'll get quicker unaided cold starts in cold weather with 5W40, but a 10W30 like Rotella T5 would be an excellent choice too.


I'd submit that won't matter worth a hoot in NC.

To be able to really measure "quicker", we'd have to come up with some measurment device that would be able to discern the time from first crank signal to steady rpm state.

Then, we'd have to run a minimum of 30 start cycles for each oil considered; at least 60 if only contrasting the forme Delo with T6, or even 30 more if you throw in a 10w-30 HDEO. All this needs to be done to establish the statisical averages and sigmas so that you know what the ranges and variances are.

And to make it fair, we'd have to let the engine come to a steady temp (back to cold) for each trial, and yet also provide a steady ambient temp (probabaly in the wee-hours of the morning when temps are often the most steady). And because this is (presumably) about winter starting, we'd have to wait for that season.

Etc, etc. Data-driven experiments are very meticulous and need as many inputs held consistent as possible. That is the only way to fairly, accurately decide what might be "better" for this situation.

Or, we could just realize that a syn is not "needed" in NC, no matter how much mythology and rhetoric surround it ...
 
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