Big fuel economy drop after changing from synblend to full synthetic???

There is some information out there to suggest that synthetic oil will reduce fuel mileage. If memory services me correctly it's due to some kind of temporary shearing of the oil in the bearings that occurs more with conventional oil.
Honestly, you can't make this stuff up.
Some fleet management noticed this. I also read an article about this from ...Lubrizal maybe?????
here is the article...look at disadvantages of synthetic oil
 
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There is some information out there to suggest that synthetic oil will reduce fuel mileage. If memory services me correctly it's due to some kind of temporary shearing of the oil in the bearings that occurs more with conventional oil.
Honestly, you can't make this stuff up.
Some fleet management noticed this. I also read an article about this from ...Lubrizal maybe?????
here is the article...look at disadvantages of synthetic oil

The standard oil recommendation for this engine is synblend 5w20, I don't know if that counts for anything. Turbo dual injection engine.
 
Was the oil overfilled ? The top dot is MAX HOT - the oil should be in the lower crosshatch area cold.

My 2.0 seems to run Ralph when a bit over . Doesn't make sense as the volume change is minimal.
Regardless, maybe something going on in the CC air pulse dynamic with the PCV and the air metering

Give the DP a chance to normalize. Sometimes a hard run will get some EP plated out and it will settle back into a good rhythm.
 
There is some information out there to suggest that synthetic oil will reduce fuel mileage. If memory services me correctly it's due to some kind of temporary shearing of the oil in the bearings that occurs more with conventional oil.
Honestly, you can't make this stuff up.
Some fleet management noticed this. I also read an article about this from ...Lubrizal maybe?????
here is the article...look at disadvantages of synthetic oil


Interesting from Machinery Lubrication...

  • Synthetics may be more prone to additives precipitation during cold storage conditions. This stratifies certain additives which can potentially lead to their complete separation from the oil.
  • Multi-grade motor oils using synthetics may exhibit slightly less fuel economy at highway speeds compared to mineral oil. This is due to the fact that mineral oils require more viscosity index improvers (an additive) than synthetics. This additive contributes to reduced viscosity friction by a mechanism known as shear-induced temporary viscosity thinning.
AdvantagesDisadvantages
Advantages and Disadvantages of Synthetic Oil
Resistant to oxidation and chemical degradationMore expensive
Withstands temperature extremes better (cold and hot)Possible additive precipitation/separation
Flows better at cold temperaturesSlightly lower fuel economy at highway speed
May produce less sludge and surface deposits
Longer oil change intervals
More robust film thickness at higher temperature and higher loads
 
STORY TIME! So a company recruited me to come work for them and I received a low mileage 2021 Ford Bronco Sport as my work vehicle. This vehicle has the 1.5L Dragon 3-cylinder Ecoboost engine with dual injection. Maintenance history is that the FF was changed back in December 2021 after 9300 miles or so. The company has a contract with Valvoline Instant Oil Change to have basic maintenance services performed there.

At the time that I inherited this vehicle it had another 9300 additional miles on it since it's last oil change which happened to be using Valvoline 5W20 synblend. So twice it has been run to approx 9300 miles on a synblend. What I did notice before I got this most recent oil change between the 18000-19000 mile mark was that vehicle was getting what I would consider to be exceptionally good gas mileage, averaging 33-34 MPG per tank while most others are get mid-20's MPG for fuel economy.

Since I got the oil changed to Valvoline Full Synthetic Maxlife 5w20 (that's what VIOC put in when I told them I wanted full synthetic this time) the fuel economy has since dropped to 25-26 MPG.

I have similar driving patterns every single day which is primarily at highway speeds and I drive at or slightly above the speed limit and usually in normal or economy mode in an attempt to maximize fuel economy. Other variables to consider are that the weather is improving as far as temperatures go and tires are at recommended pressure.

I want to know what the honorable.members of BITOG think about this one 🧐
It's a f-l-u-k-e .........but Pick econ mode and stick with it for the entire fuel run. See what happens. Advice> Best not to tell the boss/vehicle owner what oil to run. .02
 
Hope the 1.5L 3-pot is better than last 1.0L 3-pot.
The 1.0L Ecoboost seemed to be a hit or miss. One member here went 230k on it before the timing belt broke, somewhat reliably and efficiently. While some other owners suffer from high fuel consumption, overheating issues (mostly due to cheap plastics for coolant system), or melting pistons, or just straight up lemons across the board.
The 2.5L was definitely the right choice. Reliable, efficient, good power, known to hit very high odometer milestones (with proper maintenance).

I saw this video and thought I should share it with you:

 
STORY TIME! So a company recruited me to come work for them and I received a low mileage 2021 Ford Bronco Sport as my work vehicle. This vehicle has the 1.5L Dragon 3-cylinder Ecoboost engine with dual injection. Maintenance history is that the FF was changed back in December 2021 after 9300 miles or so. The company has a contract with Valvoline Instant Oil Change to have basic maintenance services performed there.

At the time that I inherited this vehicle it had another 9300 additional miles on it since it's last oil change which happened to be using Valvoline 5W20 synblend. So twice it has been run to approx 9300 miles on a synblend. What I did notice before I got this most recent oil change between the 18000-19000 mile mark was that vehicle was getting what I would consider to be exceptionally good gas mileage, averaging 33-34 MPG per tank while most others are get mid-20's MPG for fuel economy.

Since I got the oil changed to Valvoline Full Synthetic Maxlife 5w20 (that's what VIOC put in when I told them I wanted full synthetic this time) the fuel economy has since dropped to 25-26 MPG.

I have similar driving patterns every single day which is primarily at highway speeds and I drive at or slightly above the speed limit and usually in normal or economy mode in an attempt to maximize fuel economy. Other variables to consider are that the weather is improving as far as temperatures go and tires are at recommended pressure.

I want to know what the honorable.members of BITOG think about this one 🧐
Old driver drove slower.

Trust me, I drive fast so I get less gas mileage than I should.
 
Good info @wemay @WobblyElvis
I like machinery lubrication

Disadvantages of syn:
"Slightly lower fuel economy at highway speed"

What's the definition of "slightly"?
I would think 1-2 mpg max. No?

Btw, some average or non-physics people say "synthetic is more slippery ... that's why it leaks!"
If that's true, shouldn't we get better mpg? :alien:

Another reason to avoid dino now:
"shear-induced temporary viscosity thinning."
 
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There is some information out there to suggest that synthetic oil will reduce fuel mileage. If memory services me correctly it's due to some kind of temporary shearing of the oil in the bearings that occurs more with conventional oil.
Honestly, you can't make this stuff up.
Some fleet management noticed this. I also read an article about this from ...Lubrizal maybe?????
here is the article...look at disadvantages of synthetic oil
Very interesting, Thanks.
 
The plot thickens. Wasn't there a recent thread about Ford recommending syn-blend (as oppose to syn). Maybe it's a mpg related recommendation. A little "temporary" shear will take VERY LONG to kill your engine but the mpg gain is immediate. Kind of like cafe type improvements. :unsure:
 
OT, but 9K seems like an awfully long interval for a fleet vehicle. All of the companies I’ve worked for required their fleet vehicles to be serviced every 5K.

It is up to the person who has been assigned to the vehicle to keep track of when maintenance needs to be completed. Many, if not most, people likely neglect to think about it oftentimes unless or until it is long overdue.

The person at the company who is actually in charge of overseeing the vehicles said that she is contracted with Valvoline to do oil changes every 7500 miles but that does not necessarily mean that it happens at or around that mileage with with any consistency whatsoever. I've read somewhere that Ford actually recommends a maximum interval of 10,000 miles for this engine on synblend oil which I think is a bit crazy.
 
When I change the oil a habit I have is to clean the MAF sensor. Also try a bottle of Techron FI cleaner. Not to make a habit of it but since you have the issue…
 
It is up to the person who has been assigned to the vehicle to keep track of when maintenance needs to be completed. Many, if not most, people likely neglect to think about it oftentimes unless or until it is long overdue.

The person at the company who is actually in charge of overseeing the vehicles said that she is contracted with Valvoline to do oil changes every 7500 miles but that does not necessarily mean that it happens at or around that mileage with with any consistency whatsoever. I've read somewhere that Ford actually recommends a maximum interval of 10,000 miles for this engine on synblend oil which I think is a bit crazy.
Strange. Are the vehicles owned by the company or by a fleet company?

The fleet companies usually do an excellent job of tracking the vehicle's mileage and harassing the assigned driver when it is due for maintenance.
 
Strange. Are the vehicles owned by the company or by a fleet company?

The fleet companies usually do an excellent job of tracking the vehicle's mileage and harassing the assigned driver when it is due for maintenance.

My company, like many, has many people wearing multiple hats as far as duties are concerned and frankly the one person that we have that keeps track of that stuff is overwhelmed with just doing every other job that they have to do as well. I am too so we really don't have time to micromanage the maintenance details for our fleet vehicles. Our contract states to have item completed every 7500 to 10,000 miles and so far that has not been an issue.
 
STORY TIME! So a company recruited me to come work for them and I received a low mileage 2021 Ford Bronco Sport as my work vehicle. This vehicle has the 1.5L Dragon 3-cylinder Ecoboost engine with dual injection. Maintenance history is that the FF was changed back in December 2021 after 9300 miles or so. The company has a contract with Valvoline Instant Oil Change to have basic maintenance services performed there.

At the time that I inherited this vehicle it had another 9300 additional miles on it since it's last oil change which happened to be using Valvoline 5W20 synblend. So twice it has been run to approx 9300 miles on a synblend. What I did notice before I got this most recent oil change between the 18000-19000 mile mark was that vehicle was getting what I would consider to be exceptionally good gas mileage, averaging 33-34 MPG per tank while most others are get mid-20's MPG for fuel economy.

Since I got the oil changed to Valvoline Full Synthetic Maxlife 5w20 (that's what VIOC put in when I told them I wanted full synthetic this time) the fuel economy has since dropped to 25-26 MPG.

I have similar driving patterns every single day which is primarily at highway speeds and I drive at or slightly above the speed limit and usually in normal or economy mode in an attempt to maximize fuel economy. Other variables to consider are that the weather is improving as far as temperatures go and tires are at recommended pressure.

I want to know what the honorable.members of BITOG think about this one 🧐
Those are nice vehicles! We have a new '21 Bronco Sport Badlands edition & love it.. w/2.0L Ecoboost upgrade its quick & super smooth! I think you did the right thing switching to "full synthetic" oil. As long as you stayed w/same viscosity 5w20..which you did.. i would chalk it up to coincidence. Reset your mileage indicator in computer.
 
My company, like many, has many people wearing multiple hats as far as duties are concerned and frankly the one person that we have that keeps track of that stuff is overwhelmed with just doing every other job that they have to do as well. I am too so we really don't have time to micromanage the maintenance details for our fleet vehicles. Our contract states to have item completed every 7500 to 10,000 miles and so far that has not been an issue.
Be sure to keep the "full synthetic" 5w20 in that vehicle I suggest. It will surely run better & not have issues while in your hands!
 
There is some information out there to suggest that synthetic oil will reduce fuel mileage. If memory services me correctly it's due to some kind of temporary shearing of the oil in the bearings that occurs more with conventional oil.
Honestly, you can't make this stuff up.
Some fleet management noticed this. I also read an article about this from ...Lubrizal maybe?????
here is the article...look at disadvantages of synthetic oil
Hard to believe! As "full synthetic" is so slippery. Would never use any less than semi-synthetic in ANY newer vehicles! We own a '21 Bronco Sport Badlands edition & '20 Ranger XLT FX4. Both vehicles have been excellent w/over 25k mis so far & we use Pennzoil Ultra Platinum oil w/Motorcraft filters exclusively.
 
For S&G's....add a bottle of good-quality fuel injector to a tank and see if that changes anything.
9300 miles twice on a bulk sy-blend just might be leaving some volatity-related deposits that need cleaning.
Unlikely? Sure....but give it a try.
 
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