Fuel Quality, Temperatures and MPG’s

NCJL

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So for the first time I fueled using B20. I only topped off a half a tank. I have always used D2 until this time. I noticed a drop in MPG.
I remember reading the owners manual when I first purchased saying something like MPG and maintenance will be affected by the use of bio mix fuels. I always used D2 with this in mind.

So this got me thinking. What type of diesel fuel are others running? Could this be a reason for the differences reported with MPG?

Also in other Diesels I have owned. The BioDiesel fuels always seemed to make the engine run hotter than D2 would.
Once again is the type of fuel used adding to the higher temps some are seeing with their ED?

I have used D2, except for 1 recent 1/2 a tank of B20, exclusively. I seem to have higher than the normal MPG and have never overheated when pulling my 4K trailer. I pulled the Grapevine in SoCal with 112 ambient temps no issues.

Just thinking.
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Gorilla57

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Aren’t you limited to B7 maximum? My Ram Eco specifically says that.
 
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NCJL

NCJL

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Not sure exactly. I was fueling at one of my normal D2 spots. I fueled than noticed they had changed to B20. I figured only half a tank, shouldn’t be a big deal.

I’m going to break out the owners manual later today to verify. Do not remember the specifics, just my takeaway after reading to only use D2.
 

CWRUYOTE

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From the 2021 diesel manual, starting on page 567--max of 5% biodiesel blend, but up to a 20% biodiesel blend can be used, provided oil's changed more frequently:
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GSLSE21B

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B20 will consume styrofoam and your fuel system warranty 👍
 
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NCJL

NCJL

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So I renamed the post. Trying to get more traction with the type of fuel we are using in our EcoDiesel’s.

I had extra time this morning. Stopped by the place that changed from D2 to R95. I haven’t searched what R95 truly represents, I did take a picture of what was listed on the pump. Not good. Minimum 20% bio diesel.

The half tank I used of the R95 averaged 3 MPG less than normal. I do the same exact drive during the week. Mostly short trip city type driving. Engine temps are never consistent during this time.
I drove this bad tank of fuel to as close to empty as I could, fueled up with “D2” from a different station. Noticed a slight difference, better. With this tank of fuel I did a 300 mile round trip to the Yosemite area. I wasn’t towing anything. This type of trip would normally see 29 plus MPG if I’m trying to get good MPG. I only got 27 MPG.

In my area I’m noticing a price difference between stations (about 12) of about .30 cents per gallon. The lower price usually has advertised bio diesel. Some lower prices still say D2. The higher prices only list D2. Thinking even though it says D2 maybe not!

We, the forum, have also proved Dealers and Oil change Stations don’t use the correct oil a lot of the time.

Just thinking.
Not using real D2 with the proper spec oil may be the biggest factors with MPG, Engine Temps and Engine longevity.

66F62EB2-6BE5-4C33-AE07-EAA445CB3487.jpeg
 
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NCJL

NCJL

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I have about 1.5 hours of BART train time during the week on a daily basis to try and educate myself. I’m using this time lately to learn about Diesel fuel quality.

First, you can find info that will agree with whatever you want your opinion to be.
With this in mind I’ve mostly read what the Manufacturers of Diesel Fuel have published along with others that use ASTM standards with documentation showing the testing to meet or exceed the ASTM standards using ASTM testing procedures.
In regard to fuel additives and engine oil.
Most companies do not provide any documentation showing what they claim or at least not easily accessible documentation.

I’ve only found one fuel refiner that published its own Diesel Fuel Quality document (Chevron). Others refer you directly to ASTM D975, without interpretation.

Summarizing.
Diesel fuel has about a 10% window of quality depending on many factors leaving the Refinery. After Diesel Fuel leaves the Refinery additives may be mixed in by the various handlers for many reasons Fuel Stability, Fuel Conductivity, Antifoam, Contamination control, flow agents and so on.
ASTM D975 is the minimum standard for D2. Different manufacturers do different things to meet this minimum. Doing this changes the mix in regard to Cetane, Lubricity levels, ETC. For example ASTM D975 standard for cetane is 40. Do to many different factors a refiner may increase the cetane level to 46 to control another minimum regarding smoke. Lubricity levels are also not consistent, they only must meet the minimum. Lube levels are changed once again for many different reasons.
All decisions made in the manufacturing of diesel is made with cost as a priority. I’ve seen this statement mentioned several times in my reading.
Engine manufacturers blame fuel and fuel manufacturers blame engine manufacturers.
Read many times that a more modern ASTM D975 standard is needed.
Engine Manufacturers Association and Fuel Manufacturers have meet to create this standard with no agreement. Premium Diesel was an idea that didn’t take off.
D2 in California is generally considered to have higher Cetane levels due to lower Aromatic requirements. Higher Cetane levels lower Aromatic levels. Lubricity additives by Refiner are also common in California. Another way to lower Aromatic levels is hydrotreating further than needed to remove Sulfur. Doing this requires adding additives to raise Lubricity.
Most info is old. The Chevron document was dated 2007 and easily found.
Fuel Manufacturers get a tax credit up to a $1 per gallon for renewable/bio diesel.

I’ve never been a big fan of fuel additives. Try to only use when definitely needed. After doing all the reading with Diesel quality I’m starting to think differently.
 
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NCJL

NCJL

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Just drove the JLURD with trailer to the Yosemite area. 140 miles one way. Camped now will do the return Sunday.

Ambient temps in the 90’s.
Highest oil temp was 246.
Highest coolant temp was 228.
21 mpg.
I did use Lucas fuel stabilizer with this tank.
This trip does have about a 7 mile 6% grade. This is a single lane with speeds from 20mph to 35mph. Lots of 90 degree turns.
Pulling 3900lbs trailer.
RPM mostly in the 2K range.
 
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