8.1 Fuel Mileage

[JJ Simba05 FLSTCI02]

Looking for input

I have a 2005 W22, I typically get about 6 to 6.5 MPG running 70 MPH. At 20,000 miles I changed the oil and put in Mobil 1 synthetic for trucks. I went for a 2000 mile trip and averaged 7.75 MPG @ 70 MPH. This seems like quite a stretch for synthetic oil to make that much of a difference.

Anyone else out there experience anything like this?

[JJ Simba05 FLSTCI02]

Looking for input

I have a 2005 W22, I typically get about 6 to 6.5 MPG running 70 MPH. At 20,000 miles I changed the oil and put in Mobil 1 synthetic for trucks. I went for a 2000 mile trip and averaged 7.75 MPG @ 70 MPH. This seems like quite a stretch for synthetic oil to make that much of a difference.

Anyone else out there experience anything like this?

[Trek-Cyclist]

Nope! I get 7.8 MPG at 62 to 65 MPH Towing the Saturn. Use QuakerState Advanced Full Syn..

[BellaBo]

I'm on a trip from Florida to South Carolina right now. Pulling max weight and toad, running 55 mostly secondary roads averaged 7.3 mpg. 10,000 miles on engine still dino oil.

[roy goble]

I drove 8733 miles last year and used 1154.2 gals. for an average of 7.57mpg at 62-65 miles per hour. Had ultrapower tune in Quartsite in January and have driven 1612 miles since. Used 193.2 gals. for an average of 8.34 mpg at 62-65 miles per hour. I weigh 21910 gross plus my toad which is a 2000 Suzuki Grand Vitari. Hope my mileage holds up, we are planning on driving about 11,000 miles this year.

[ghamblen]

We have the ultrapower tune and we average just a shade over 8.2 mpg at 60 mph. Use Mobil 1 syn. In Illinois were the speed limit is 55 mph and the ground is flat as a pancake we can get just a shade over 9mpg sometimes but between 8.5 and 9.0 most of the time. Out west pulling the hills we get between 7 and 7.5 mpg. Usually drive 60 mph with cruise control and if I have to turn off the cruise I use as light a foot as possible. Can't do much about hills and winds. Lots of miles planned this summer. With the price of fuel rising it might be an expensive summer.

["007"]

roy goble welcome to irv2.
Thanks for joining in the discussion.
Before I got the ultra upgrade was getting only 6.1-6.9 at 60mpg and Mobil 1. After the upgrade 8.1-9 over same route to back home.
If it holds to that I will be happy the way gas is going up.
roy enjoy the forums and do post often.

[retired2001]

I just filled up on Thursday for the first 400 miles on the new Adventurer. I got 5.97mpg avg. pulling my '04 Crew Cab Z/71. I drive @ 60mph and satisfied with this mileage for the first tank. Hoping for better as time goes by.

[timp]

I get a little over six towing a flatbed trailer with a Rhino, two quads and cross bed tool box. My trips are always windy and I'm sure that hurts mileage a little.
Tim

[Geechee]

I spent 25 years working with the development and manufacturing of gas and diesel fuel systems. In that time, and in my studies to earn the degree that allowed me to do so, I learned a couple of things. One, it takes a certain amount of fuel per liter to fill a combustion chamber at a given RPM. The larger the displacement the more fuel/air mixture that is required. Two, to increase HP and Torque you have to provide a sufficient air fuel mixture to influence the power band. Three, doing so requires more and not normally less fuel to be burned. Therefore please explain to me how with only the Ultra Power ECU software changes can one obtain better MPG at the same road speeds? Now if I am missing something and the package includes a change to a higher final drive ratio, then perhaps you can convince me. If not then to do 60MPH will require the same number of engine RPM's before and after. A MH is just a heavy box on wheels that has a much higher coefficient of drag and rolling resistance, than a pick-up. Therefore how can spending big bucks for the package allow you to see mileage results that approach those of a pick-up? Check the EPA results for an 8.1l in a GMC pick-up if you think I am pulling your leg. Next time you are driving down the highway at 60 – 65 MPH stick your hand out the window with your fingers pointed skyward. Then make a fist and repeat. That is a quick lesson in the difference between the drag coefficient of your MH and a pick-up. Now factor in the 10,000+lbs in extra weight and tell me you really think a MH will get anywhere close to the MPG a pick-up will? I have gotten an average of 7.25 MPG for the 35k miles I have driven my MH. That was during my travels through 43 of the lower 48 and 5 Canadian provinces. According to the data stored in my ECU I have at least once reached 4600+ RPM's and a reported top speed of 79 MPH. I will keep by bucks and pass on any add on until someone can provide documented proof from an independent testing group such as the SAE.

[Brazels RV Performance]

GEECHEE,

Truck's with an 8.1L engine are getting 12-13 MPG.Coach's get 6.5-7.2 on average stock,UltraPower programmed coach's get 7-9.8,that still does not equal a more aero dynamic,3.5 ton pick-up truck.Our UltraPower programming has a lifetime warranty and a money back gaurantee.And as you can see in the postings there is quite afew satisfied customers.

[Brazels RV Performance]

Hey Front Ranger,

Does anybody know what the main job of a cat converter is???It's to burn off unburned fuel left over from the combustion chamber.Now let's say that 69% of the air fuel mixture is burned for power and the remaining amount is burned at the cat's.If you could increase the 69% to let's say 87% that's roughly a 20% increase.Burning that extra fuel will give you more power and better mileage...Make sense? Most Coach's go from getting 6.5 MPG to 8.2 MPG that is a 21% increase.Some get more mileage increase some get less,but everyone who get's UltraPower get's a smoother more powerful engine...I gaurantee it


Oh yeah one more thing,your speed limiter is set at 80 MPH from the factory.

[ghamblen]

I had the ultrapower tune performed on our motorhome and I have received an increase in mileage of 1.1 mpg, documented the old fashioned way, miles driven divided by gallons used. I have also noticed an increase in power compared with the pre-tune days, driving the same routes. My mileage varies everywhere from just over 7 to as much as 9, depending on road conditions and winds. The average is a shade over 8.2. That doesn't look like anything close to the mileage of a pickup truck so I don't know where Geechee is getting those numbers. If my pickup only averaged 8 mpg I wouldn't have it very long. I still drive the same 60 mph with cruise control and if I have to turn off cruise control I use as light a foot as possible. Not much you can do with hills and winds. An increase of 1.1 mpg doesn't sound like much but since I intend to keep this motorhome until it goes belly up I will definitly recover the cost at today's fuel prices. I was also concerned about the cost of the tune when I had it done, but so far the numbers don't lie. I now get another 80 miles per tank full. Once the cost of tune is recovered I get those 80 miles for free.

[Geechee]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">GEECHEE,

Truck's with an 8.1L engine are getting 12-13 MPG.Coach's get 6.5-7.2 on average stock,UltraPower programmed coach's get 7-9.8,that still does not equal a more aero dynamic,3.5 ton pick-up truck.Our UltraPower programming has a lifetime warranty and a money back gaurantee.And as you can see in the postings there is quite afew satisfied customers. </div></BLOCKQUOTE>

Mike,

Is what you are saying that your software changes the fuel mixture to the leaner side and therefore less unburned fuel is reaching the cat? Does your lifetime warranty protect purchaser like ghamblen <BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">since I intend to keep this motorhome until it goes belly up </div></BLOCKQUOTE> from shorten engine life expectancy? If you are burning less fuel how do you obtain the higher HP and torque ratings. I must have been sleeping that day in class.

Mike said<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">
Does anybody know what the main job of a cat converter is??? </div></BLOCKQUOTE>

Right out of a 2006 text on the subject:
"Its task is to convert HC(hydrocarbons), CO (carbon monoxide), and NO2 (nitrogen oxides), which arise during the combustion process, into harmless components. The end products are H2O (water vapor),CO2
(Carbon Dioxide)and N2(nitrogen." Yes the hydrocarbons are the unburned fuel portion of the air/ fuel mixture , but in no calculation I am aware of equal to the 15 - 20% levels necessary to justify the same percentage MPG increases claimed.

Lastly, the fact a pick-up can obtain a 70% improvement in MPG can be explained by the lower gross vehicle weight, lower rolling resistance and much lower coefficient of drag. None of which, at least that I am aware of, are addressed by your "Tune Up".