Credibility has been completely lost.
Oh well.

 

Years ago I had set out to try to understand why the owner’s manual for the Gen 1 3.5L Ecoboost only listed the 5w-30 semi-synthetic as a recommended oil when Motorcraft makes a full synthetic in 5w-30. I never found a reason. The owner’s manuals for the Gen 2 3.5L EcoBoost and the 7.3L gas do list both the 5w-30 semi-synthetic and the 5w-30 full synthetic as recommended oils. Some speculated that it was because all of Ford’s original testing of that Gen 1 engine had been done with the semi-synthetic, so it was just a CYA thing. I even tried to find a negative to full synthetic oils when I was searching for that answer. The only thing I found was cost. I too am curious to know what the downsides could be? In my mind I had wondered if there could be some additive package that would not stay dissolved in full synthetic, so a semi-synthetic would give the best result. Of course I have not read this, and I have zero basis for this. I was just kicking around ideas back then.

 

From Castrol…
“There is no definition of how much synthetic needs to be included in a semi or part synthetic motor oil.“

https://www.castrol.com/en_us/united...synthetic.html

From Amsoil…
“Lastly, there are no industry specifications or regulations that define a minimum amount of synthetic base oil that must be present for an oil to be classified as a synthetic blend or semi-synthetic.”

https://blog.amsoil.com/the-pros-and...ic-blends/amp/

You don’t know what you’re getting with semi synthetic and synthetic blend oils.
They can add one drop of synthetic oil to a 55 drum of conventional oil and label it semi synthetic or a synthetic blend oil.

I use Mobil 1

 

No to totally hijack this into an oil thread but even what constitutes a synthetic runs the range from group 3 (hydrocracked), group 4 (PAO) and group 5 (ester) each with their own Pro's and Cons. That said for the vast majority of automotive applications a group 3, blended or fully synthetic is more than enough. Still curious to hear why the blend is a better option for the synthetic in this application?

 

I know it takes time to try all the suggestions, but to the OP, I have a vested interest in your outcome since I own a 7.3L. I am looking forward to hearing your progress as you troubleshoot this.

I by no means am downplaying the lifter issue or cylinder issue, but I do want to say don’t jump to conclusions and write it off as internal just yet. I saw a guy on YouTube, Automotive Inquiries I believe, who really seemed to imagine lifter issues all in his head, or it was all just click bait. He presented no proof of lifter issues to the audience, and he never let the audience hear the truck run. Dealerships told him there was no problem as well. He eventually traded it in. I know you have a miss and a real issue. I just wanted to try to add some calm while you get it figured out. The internet can play games with your head. Ha, I was about to perform a $100 oil change just because of this thread, but luckily I stepped back to take a breath.

 

I’ve been watching these 7.3 failures closely. Especially since it seems the common theme with the lifter issues are high idle hours.

I have over 2000 idle hours on my 2020 7.3L out of 3250 total hours.

I’ve been doing 200-250hrs OCI intervals using synthetic oil, usually around 3-4000 km

 

Haha...all credibility lost I guess. Well let me drop some knowledge on you. Synthetic oil doesn't work properly until it gets up to temperature, it's actually kind of crystalizes and coats the metals with a paint like coating when its cold. Look up the some 5.0L teardowns if you dont believe me. Aluminum bearings are also softer, synthetic oil can be aggressive on aluminum surfaces.

Why does this matter for engines today, Todays engines have smoother cylinders, harder rings, low friction bearings...all for gas mileage and efficiency. This also means they burn oil when its cold. Once the engine warms up, they stop burning oil and the synthetic oil does its job. Hence the synthetic blend. The consumer wants a daily driver with good mileage, high horsepower and torque, and can pull like a mother.

 

I just checked the owner’s manual, and it says 200 hrs, 5,000 mi, or 6 months for extensive idling. You’re right in line with what Ford calls for. Does your IOLM show it’s time for an oil change at 200-250 hours when you’re idling a lot? What percentage is remaining? I am curious if the IOLM is accurate under what Ford calls special operating conditions?

 

I change mine every 5k miles because I tow a lot and at 5k miles since I reset and almost 4k of those miles were towing 17k lbs my "I"OLM says 43%. It has never been below 40% when I've reset it. Even when all 5k miles were hooked to the trailer.

 

Good points indeed!
But I doubt that any of the 7.3’s that have had lifter/cam failure, cylinder bore scoring or piston skirt failure were using full synthetic oil. I bet that most, if not all were using the recommended Motorcraft semi synthetic oil and filter.

 

yep u right. Any ideas how much it’s going set me back

 

You confirmed this? Jegs has long blocks for $8k. Not sure how that compares to other places though.

 

yep it’s confirmed. I alright thanks I’ll have to look into jegs and summit.

 

Do you also believe in chupacabras?

 

I’m I missing something here, reading though this thread?
Why does the OP need a $8k long block?
If I’m not mistaken he hasn’t even confirmed the lose of compression or confirmed the cause of failure.