Does winter diesel give less mileage than summer blends? - PeachParts Mercedes-Benz Forum

edge · #1 11-10-2009, 03:54 PM

I calculated recently that I got 25mph on the hioghway whereas over the summer the same trip to Philly from CT was giving me 33mph. What gives, is diesel blended differently for the cold months?

cscmc1 · #2 11-10-2009, 04:09 PM

Quote:

Originally Posted by edge

I calculated recently that I got 25mph on the hioghway whereas over the summer the same trip to Philly from CT was giving me 33mph. What gives, is diesel blended differently for the cold months?

Yessir... different blend. Bummer, huh?

Wodnek · #3 11-10-2009, 04:18 PM

Winter diesel is usually cut with kerosene (Diesel #1), which has a lower energy yield, which directly causes lower mileage in most uses.

F18 · #4 11-10-2009, 04:25 PM

As Wodneck said...it is diluted with kerosene to lower the gel point and it packs a lower punch so the engine has to work a little harder.
In some extreme cases depending on the location's winter temps the fuel could contain as much as 20%+ kerosene.

edge · #5 11-10-2009, 11:20 PM

Quote:

Originally Posted by cscmc1

Yessir... different blend. Bummer, huh?

Yeah, bummer. My 300D is my highway car so I guess in the winter I
ll just use my E420 or 328iC instead. It's a big difference.

#6 11-10-2009, 11:24 PM

Well, 25 mpg sounds like the low end of normal and 33 sounds too high, regardless of fuel blend. I don't see a fuel blend resulting in a 25% difference.

soothappens · #7 11-11-2009, 12:23 AM

Quote:

Originally Posted by Wodnek

Winter diesel is usually cut with kerosene (Diesel #1), which has a lower energy yield, which directly causes lower mileage in most uses.

Less energy , lower mileage ,higher price ........................... sounds about right!!!

Biodiesel300TD · #8 11-11-2009, 12:24 AM

Winter diesel does yield less mpg, but I wouldn't rely on one tankful to tell you want the milage is, since milage is so heavily affected by driving habits. You could also need a new air filter, fuel filters, and air in your tires. I find that I usually need to add a few psi when the weather gets colder to get my tires back up to pressure.

soothappens · #9 11-11-2009, 12:48 AM

Does biodiesel yield the same results ?

Biodiesel300TD · #10 11-11-2009, 01:10 AM

Quote:

Originally Posted by soothappens

Does biodiesel yield the same results ?

B100 or B99 will typically reduce milage by 5-7%. So people usually see a drop of a few miles with the high blends. Lower blends usually don't cause much of a drop. I get 26mpg in my turbo 123 running B20.

BoiseBenz · #11 11-11-2009, 01:14 AM

Same tires year round. Same pure city route year round.

Summer 22-23.
Winter 19-20.

About one tank per month.

Graplr · #12 11-11-2009, 09:38 AM

Quote:

Originally Posted by F18

As Wodneck said...it is diluted with kerosene to lower the gel point and it packs a lower punch so the engine has to work a little harder.
In some extreme cases depending on the location's winter temps the fuel could contain as much as 20%+ kerosene.

In some areas in the coldest part of the year it is much higher than 20%. Even closer to 50/50.

Quote:

Originally Posted by Craig

Well, 25 mpg sounds like the low end of normal and 33 sounds too high, regardless of fuel blend. I don't see a fuel blend resulting in a 25% difference.

I agree that a 25% change in mileage is NOT due to a fuel blend. Especially since it is only the beginning on November. Usually the blend of D1 slowly goes up as the winter goes forward and we get colder. Right now the blended fuel is a low percentage.

dcotejr · #13 11-11-2009, 09:49 AM

Is there a general rule of thumb as to what blend ratios are used based on low temps in a region?

The reason I ask is that I live in Alabama, and if it does get to freezing, it rarely stays that way for long.

And in the past, I have noticed decreased mileage when traveling to New England in the wintertime... Some decrease here in the south, but I didn't know if that was just more energy being translated into keeping the engine at temp...

okyoureabeast · #14 11-11-2009, 11:06 AM

Where were you driving and how fast?

I ask, becuase I've been hauling a lot of people around in the hilly section of college town. I manged to bring my excellent 25mpg down to 16.9 using S gear to get speed going up and down those hills

Driving does greatly affect mpg. As you can see above.

Graplr · #15 11-11-2009, 11:20 AM

Quote:

Originally Posted by dcotejr

Is there a general rule of thumb as to what blend ratios are used based on low temps in a region?

The reason I ask is that I live in Alabama, and if it does get to freezing, it rarely stays that way for long.

Yes. I highly doubt there are cold weather blends in areas that rarely drop below 32F. I'm not 100% positive but I believe D2 is good down in the 10sF range. At most it is a very small blend of D1/additives in it.

Quote:

Originally Posted by dcotejr

And in the past, I have noticed decreased mileage when traveling to New England in the wintertime... Some decrease here in the south, but I didn't know if that was just more energy being translated into keeping the engine at temp...

Yep. Less BTUs in D1 so one will get less mileage on winter blends.

Some fuel stations post there winter blends and the timeline for the different blends at the pumps. If they are not posted, they should be able to get you the info if you ask them.