Community Forums

rmmpe · 06-26-2007, 09:50 AM

Though there isn't much we can do about it, that would also be an interesting topic.

OldForester · 06-26-2007, 10:35 AM

In response to Kip Barker's question, I looked at my spreadsheet and found that in my first 8500 miles (August through December 2006) I averaged 7.65 mpg. From January to this month, June, on 9000 miles, I averaged 7.56 mpg. I also looked at thowing December's miles into the ULSD category, and found that difference was 7.7 vs 7.5 mpg.

I took much of the same long distance trips -- to Texas and back via California both last fall and this spring, and the side trips were similar, and I always towed the 4 Runner, and always tried to run in cruise control as much as possible at 60-62 mph. So assuming there wasn't a big difference in headwind each time, it looks like the ULSD may have cost 0.1 to 0.2 mpg.

Ted III · 06-27-2007, 02:27 PM

It would appear that we all pretty much agree that 7.5 MPG is resonably standard. Anything beyond that is really terrific. Let's end the post, it really is going no where.

jerry davis · 06-27-2007, 04:44 PM

Ted, some of us might be interested in the continuation of this discussion. I don't agree that 7.5 MPG is a reasonable standard. These days any tips we receive and use are important. I, for one, have slowed to 60mph and have had my average mpg jump to the 9mpg range.

Ted III · 06-28-2007, 02:56 AM

Jerry, I apologize for my comment. I was not including reducing your speed which certainly should increase your fuel mileage. I must say that I cannot get 9MPG @ 60MPH. I was more referring to the general averages of what had been posted on the forum with the exception of RobRoy.

Kip Barker · 06-28-2007, 04:44 AM

I am surprised, most people I have talked to with diesel pick ups,have found thier fuel mileage has increased since the ULSD came out.

Thanks for the info.

Kip

Beagle RC Air · 06-28-2007, 05:44 AM

In reviewing this thread it seems that we are getting excellent mileage with our 9 1/2 mpg. But let me say that we do drive slower than most when we can. 56-57 mph is hard to maintain on most freeways without impeding trafic. So we do secondary roads and take our time. We don't use cruise much and don't use the econo feature on the shift console.
Keeping the turbo boost down is key I believe if all other things are equal. We had several vehicles in the past that I put pyrometer and boost gauges on. Along with OEM fuel consumption gauge, the lessons we picked up on is, keep temp, boost and rpm down and mileage goes up. Works for us.

Ted III · 06-28-2007, 06:03 AM

BeagleRC, I am certain it does not hurt to be a truck mechanic to maintain I am sure a perfectly functioning engine. Congratulations on the mileage. It certainly makes me wonder about the cruise control which I had always felt was the most efficient way to travel.

rmmpe · 06-29-2007, 01:44 AM

Although I have yet to pick up my Alpine and cannot testify the following will be true with it or it's ilk, the basics should be consistent.

Cruise-Control is a reactionary system. While is works fine with flat terrain, it usually works poorly in hills.

Anticipating an uphill by increasing rolling speed on the downhill allows momentum to work in your favor. Cruise-Control does not anticipate and only actuates the throttle when the vehicle is already losing speed. Most often, the vehicle will then downshift.

In many cases, better economy in hilly terrain can be achieved than if it is left to the Cruise-Control feature.

Millions of Professional Drivers can't all be wrong.

On long uphills, all bets are off because the vehicle will downshift regardless.

I guess it comes down to the requirement that we be smarter than the machinery we're dealing with.

gjstacy · 06-29-2007, 08:11 AM

I'd be interested in knowing more about the economy button, as it seems that some folks are using it and some not. Does it really improve MPG? My pilot (John) has not been using it, and we don't get great MPG numbers. As a matter of fact, with our new 07, our MPG has dropped...I am assuming because of the added weight of the Smart Beds. Has anyone else with an Apex or SE experienced the same drop?

dgerstel · 06-29-2007, 10:00 AM

Gail,

The economy mode keeps the transmission from shifting as soon. The diesel engine will generally gets better economy at lower RPM. My new coach is not getting the best of mileage, but: my old coach was much lighter, new coach has VERY few miles on it, a lot of the first miles was test drives and in and out of the factory, and our trip so far has either been in the mountains or we have had bad head winds.

Dale

SteveS · 06-29-2007, 06:57 PM

I have been testing the economy mode over about 5000 miles now...with no firm conclusions. I may be averaging about .2 mpg better in economy mode but the numbers are so close that I would not swear to it...it could be misrepresented due to terrain also. However, in theory the savings will only be noticed in traffic or mountainous conditions because lower rpm for downshifting, and upshifting. So, if you are driving on the highways and shifting is not required, no difference in mileage will be achieved. Also, the most noticeable difference will be seen in traffic and mountainous conditions. Since my driving has been primarily highway I show little difference. The difference I show might very well be within the margin of calculation error, i.e. complete fill-ups or at least consistent fill-ups).

gjstacy · 06-30-2007, 07:28 AM

Dale and Steve,

Thanks for the info...I think I understand better now when to use the economy mode.

Ted III · 06-30-2007, 01:27 PM

Steve S, thanks for the info on the mode button. I have not used it very much and wondered if I was making a big error. From reading your site it appears it really does not matter either way. Thank you for your informative info.