Diesel MPG and fuel additives

tvman44 wrote:
I have checked my mpg on my old diesel several times and Diesel Kleen boost my mpg 2 to 3 mpg everytime. Not enough to pay for itself but the biist in power is nice towing. :)

Keep using it and eventually you might hit 50MPG! JK. I used it in my 12 Valve when the ULSD fuel became prominent. I was using it for lubrication. I still only got 15 unloaded most of the time. I got 20 one time with that truck. Driving 55 on a two lane unloaded. Never did it again. Averaged 15-16 most of the time not towing. Towing my boat or camper I got 11-12, sometimes 10. New truck does some better, but not enough to make it's own payment. Won't use anything in it but diesel fuel.

In my 03 I put lots a different things in the fuel. Got more smoke and power. I just picked up my 14 and I will put nothing in the fuel tank but fuel. Too many sensors and stuff to go wrong. Now I have more power than I know what to do with.

We know how to blend it here in the great white north! No gelling. :)

Garage isn't heated or insulated, but it beats scraping ice and sweeping snow off before you get in.

45Ricochet wrote:

ib516 wrote:


In the owners manuals for my last two Cummins diesels, they said not to use additives in the fuel. New ones could be different I suppose... :?

Actually I believe it says " fuel additives not needed" but I could be wrong. Can't believe you never gelled the fuel in winter, must be a warm garage :B That pour point must get pretty waxy at -30 :E

I've never gelled and my truck has never been in a garage. We hit -20 to -30f several times this winter. No additives.

Winter blend diesel doesn't gel up. Got diesel in MT, WY, SD, ND, MN, IA, and WI this winter.

ib516 wrote:


In the owners manuals for my last two Cummins diesels, they said not to use additives in the fuel. New ones could be different I suppose... :?

Actually I believe it says " fuel additives not needed" but I could be wrong. Can't believe you never gelled the fuel in winter, must be a warm garage :B That pour point must get pretty waxy at -30 :E

skyhammer wrote:

ib516 wrote:
First, read the owners manual. I'll bet there's a spot in there where they say not to use any additives in the fuel.

Second, I will never believe that adding anything to your fuel will boost mpg enough to pay for the additive - snake oil.

Lastly, the 850 lbs-ft of the tq the new diesels make, and the emissions garbage they are saddled with decrease their mpg. The 5.9L Cummins won't be matched for it's mpg and power combination with the power war and new emissions laws the new diesel engines have to deal with. It is what it is. JMHO.

Actually, there is a "spot" in the fords manual that says"Diesel fuel conditioner
Additives that will improve fuel cetane numbers may be used to
verify/enhance fuel quality. Use Motorcraft or an equivalent cetane
booster & performance improver as listed in the Maintenance product
specifications and capacities section in this chapter."

Looks like the "King of Oil Additives" learned his lesson with snake oils. :W Especially those BG oil additives.

How many miles on the truck? Someone mentioned non DEF truck. If he has the Aisin, he has DEF.

2oldman wrote:

crewstx wrote:
a RAM 3500 DRW with a 3.73 rear and ASIAN transmission. I only get about 14-15 MPG not towing at 65 on level ground and about 7-8 MPG towing a Montana fifth wheel on level..

Wow.. an honest post about mpg.

Actually if that is what OP is getting 'hand calculated' then something isn't right.

Both non-towing and towing mpg are low.

But guess that depends on whether OP's Cummins is pre/post DEF

My honest mpg......hand calculated
Non-towing....17-18 mpg
Towing......10-11 mpg (worst I every got was 9 bucking a 35 mph headwind)
4:10 diff/4 speed auto 14K 13'3" 5vr

skyhammer wrote:

ib516 wrote:
First, read the owners manual. I'll bet there's a spot in there where they say not to use any additives in the fuel.

Second, I will never believe that adding anything to your fuel will boost mpg enough to pay for the additive - snake oil.

Lastly, the 850 lbs-ft of the tq the new diesels make, and the emissions garbage they are saddled with decrease their mpg. The 5.9L Cummins won't be matched for it's mpg and power combination with the power war and new emissions laws the new diesel engines have to deal with. It is what it is. JMHO.

Actually, there is a "spot" in the fords manual that says"Diesel fuel conditioner
Additives that will improve fuel cetane numbers may be used to
verify/enhance fuel quality. Use Motorcraft or an equivalent cetane
booster & performance improver as listed in the Maintenance product
specifications and capacities section in this chapter."

The OP owns a Cummins not a Ford. There is a difference in maintenance, operating costs and recommendations like I mentioned in another thread. All diesels are not the same.

skyhammer wrote:

ib516 wrote:
First, read the owners manual. I'll bet there's a spot in there where they say not to use any additives in the fuel.

Second, I will never believe that adding anything to your fuel will boost mpg enough to pay for the additive - snake oil.

Lastly, the 850 lbs-ft of the tq the new diesels make, and the emissions garbage they are saddled with decrease their mpg. The 5.9L Cummins won't be matched for it's mpg and power combination with the power war and new emissions laws the new diesel engines have to deal with. It is what it is. JMHO.

Actually, there is a "spot" in the fords manual that says"Diesel fuel conditioner
Additives that will improve fuel cetane numbers may be used to
verify/enhance fuel quality. Use Motorcraft or an equivalent cetane
booster & performance improver as listed in the Maintenance product
specifications and capacities section in this chapter."

In the owners manuals for my last two Cummins diesels, they said not to use additives in the fuel. New ones could be different I suppose... :?