Every street fuel in the EPA areas around Chicago and Milwaukee have to conform to Reformulated Gas (RFG) regulations for "pollution" control. A lot of the aromatics are removed and either ethanol or methyl tertiary butyl ether (MTBE) added...as oxygenates.

Wouldn't matter if it is premium either. The states haven't put up any resistance to the EPA. It does reduce mileage.

Finally, there is a lot of oxygenating going on with MTBE and ethanol. Might only be 2% ethanol vs 10% as in RFG. Gasoline, and diesel, aren't like they used to be fifteen to twenty years ago. Not as many BTU's anymore.

 

By September of 2005, 25 states had banned MTBE as an additive- I believe it is now outlawed in all the states by the EPA (actually by late 2007). The removal of MTBE from gas is one of the big reasons that gasoline shelf life is now about 30 days or less without a storage or stabilizing additive.

It's still found to be pretty good stuff for dissolving gallstones in the medical industry, however.....

 

Thanks everyone. to add a little more my 02 X has 55k miles on it. tires are always inflated to 75 rear and 70 front. the trailer weighs in around 9100 lbs +/- a hudred. I`ve been towing this trailer since 06 when I bought it new. the X had 3.73`s and had had 4.30`s since 07. around town and towing mileage went up after the gear swap, but has slowly degraded the last couple of years. since I have posted this I have talked to others and they have stated a drop in mileage in the last few years also. i am going to do some experimenting on this trip with 93 octane without ethanol if I can find it and see how it does with that. the other thing I forgot to mention is the truck has become a dog with a slight headwind. it takes about 95% throttle to hold 65mph with a slight headwind. I did notice one time when I filled up in eastern WI. with mid grade the truck woke up big time!!! it pulled the trailer excellent as if I lost 2k lbs of weight.

We`ll see how this trip next week goes when we go down to the Smokies!

Thanks again!

 

That does sound pretty typical of the degrading fuel and increased ethanol.


Forgot to mention I go camping by Minocqua quite often at the clear lake camp ground.

 

In 2008 gas like diesel had been reformulated to ultra low sulfer status. This was of course thanks to our mind numbed enviromentalist. It has caused an effect on lower mileages in both cars and big trucks(semis). The more we let the goverment decide what is good for us the more we are going to pay. With every fuel change that has been made in the last 20 years to improve "pollution" we end up lowering milage and increasing the consumption of fuel. Wheres the gain????

 

i been using Kwik Trip 89 oct and do no have problems with my 6.8, 3.73, 2wd excursion with od off. I have been pulling since sept 2006 with the same mpg of 9.0 for my trips around central wisconsin. granted I90 at 65mph can be a little hairy on friday night but many people pass me when i have the 7800 lb cinder block attached (27 ft TT with super slide). i have seen with differnt tire on my Expedition a change of -3 mpg going from Bf goodrich to Dueler AT revos. i do not like the loss of 3mpg but when the snow is bun hole deep it is nice to put it 4x4 and just go.. it is worth it!

 

I would also agree that fuel blend is our(v-10) biggest enemy. I have noticed that Shell or Marathon fuel is better then then the cheap stuff. $.05 more for Shell will get you 10% better mileage. Try it out.

 

OK here are the final numbers, 1669 miles, 240 gal. = 6.95 mpg! this is ALOT better than the 5.5 I was getting on the last trip up to Minocqua WI. and almost back to the 7.5 I was getting 2 years ago. although then I wasn`t towing in the hills. so if you rid the trip of the 600 miles of hilly towing I did then I would be very close to the 7.5 I was getting. (BTW, that "lie-o-meter" is dead accurate!) and what did I do to gain back the 1.5 mpg? I ran 93 octane the entire trip. that simple! and my power also came back. I never had a problem holding 60mph going up some of the hills. and even passing some of the many slower trucks. I usually avg. 65mph. also the Ford V-10 loves 4000rpm! and BTW, I didn`t encounter anywhere near the hills going to MT, while crossing the Rockies as I did going to the Smokies! southern KY and all of Eastern TN is VERY hilly!!! even heading west on 80 going through KY is hilly. I can tell you now I`m tired of looking at hills LOL.

Just thought I`de throw this final post out here one last time to give some ideas on what the new "better gas" does to performance. it may be cleaner, but you burn more of it. so how is that any better?

Comments welcome!

 

Glad your mileage is back on track! Not sure if this has been mentioned before but sustained engine speed over 4100 rpm will eventually droop your fan clutch. When your truck/engine is cold, spin the fan, it should be stiff and not want to freely spin. There is a ball bearing on the fins of the fan clutch (usually can been seen on your back), when it droops, the ball bearing will discolor (purplish blue = high heat). Hope that helps.

BTW,just got back from Northern MI with mine. This was my first road trip without the trailer, just people and luggage. The overall mileage(hand calculated) was 13.90 which I'm very happy with. My overhead showed 14.4. I've found the overhead to be very close when towing and generally closewhen not.

 

[quote= . . . . . . (BTW, that "lie-o-meter" is dead accurate!) and what did I do to gain back the 1.5 mpg? I ran 93 octane the entire trip. that simple! and my power also came back. I never had a problem holding 60mph going up some of the hills. and even passing some of the many slower trucks. I usually avg. 65mph. also the Ford V-10 loves 4000rpm! and BTW, . . . LOL.

Just thought I`de throw this final post out here one last time to give some ideas on what the new "better gas" does to performance. it may be cleaner, but you burn more of it. so how is that any better?

Comments welcome![/quote]

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

First of all, happy "LOL" to you ( for those that do not know this, it is becoming mandatory ("to show you want to "belong") to type a few LOL's here and there).

Secondly, what you call a "lie-0-meter" is a complex computer program measuring several factors. It can be dead accurate - it can also be as much as 10% "off". You can find mine and other explanations of this in earlier "threads".

Thirdly, your mileage reports are consistant with what the rest of us get, some of the time. As repeated often in earlier "threads", the variables of wind-speed, road, tire, outside air temp., and driving habits (my habits change with my mood) make for the discrepancies. As I noted earlier, i have found as much as a 10% difference pulling the SAME grade with the SAME load at different times of the SAME day.

You are mistaken if you belive your V-10 "loves 4,000 rpm". Your Excursion is not an animate object. It is an inanimate object with no feelings, no emotion. It does not "love" or "not love" anything. All other things being equal, the faster you run your Excursion's motor, the faster it will wear out its various components and fail. However, the faster you run that motor, the more noise you will make. To some, that has value.

The faster you beat on your motor, the more power you are going to get out of it (up to a certain point). You will find that you can probably get all the power you need in the 2,500 rpm range - however, the disadvantage is, you wont make as much noise.

I personally recognize the limits of a gasoline motor over a diesel motor, regarding the ability to keep speed up on long grades when pulling heavy loads (our motor yacht with trailer is around 11,000 lbs). I find that on level ground about 2,400 rpm gives me enough power to hold 60 mph, and 3,000 rpm produces enough power to keep me moving up the long grades - of course, nowhere near as fast as a similar load and towing vehicle that is diesel powered.

My recommendation is, if you want to cruise at anything over 60 mph, while pulling really heavy loads, do it in equipment that is designed for it. Equipment that has the wheels, brakes, and tires to handle that job. At LEAST a "class 6" equipped diesel tractor. A "stock" Excursion is basically a one ton truck with a fancy station wagon body and way-too-soft springs. Stiffining the springs does not enlarge the brakes, nor change the engineering limitations designed into your steering system or frame.

And please, fellow V-10 lovers - those few of you who think our V-10's can keep up with the diesels - how do you figure displaying your ignorance benefits you ?

 

I`m only repeating what other people cal the "Lie-O-Meter" I know too how they operate and they can be very accurate. and incase I scared anyone, I don`t run my X at 4,000rpm all the time! it runs at 3000rpm at 65 in 3rd or 2600rpm in O/D. the only time it runs 4000rpm is when I`m accelerating up a hill or passing a slow moving diesel truck! and actually stiffening the springs on the X basically gets you an F250/350.

 

= = = = = = = = = = =

Please try and get the license number of that "slow moving diesel truck" you say you can pass with a "gasser" pulling a heavy load.

I would like to track him down and hire him to drive around here, so I can pass him with my "gasser". Damn, that would be so satisfying....(to actually pass a diesel-powered vehicle with my "gasser' when towing the kind of loads I pull......!)