msturtz Report post Posted February 3, 2015 We just got a Thor Palazzo 33.3 Allison MH2100 Cummins ISB 300. For kicks and giggles I wanted to see the best mileage I could get out of it. No toad but the family was along. I was able to get 15 MPG with the mode button on flat ground (other than overpasses) no wind and traveling at about 63. I was really feathering the throttle and there was no traffic. On a longer trip over a few passes with the mode button "off" I got about 11 but I wasn't trying to save fuel. Our fuel economy really goes to heck driving around the city up and down hills. We flat tow a 2007 Chevrolet Tahoe LTZ. Our old MH with the Ford V10 really didn't like to tow the Tahoe! The Cummins ISB on the other hand doesn't really care much. Share this post Link to post Share on other sites
Cookie Report post Posted June 18, 2015 Wildebill308, One of the unfortunate things about how this forum is set up is that you can't 'reply' to a particular person, so it appears that the person you 'replied' to is the one directly above your post. My comments were not aimed directly you at all, and I am sorry that you thought so. But yes, I do feel that driving the speed limit, even though it is slower that the 'flow of traffic' is the thing to do. Call me an old 'fuddy-duddy' for obeying the law, but so be it. It has been mentioned in many threads on this forum that one cannot stop a motor home as quickly as one can stop a car. The physics of the thing prove that. We all know that there is a safe following distance which is based on speed and weight. The basic rule for large vehicles, and I would say something that weighs 30,000, or 40,000 or 50,000 lbs. qualifies as a 'large vehicle', is that you allow four seconds between your vehicle and the one you are following if your are going under 40 mph, and if you are going over 40, one second for each 10 feet of vehicle length plus one additional second, or if you are going 60 miles/hour, and your are 60 feet long you should leave seven seconds between you and the car you are following. In addition, at 60 miles/hour you are traveling at 88 feet/second (no misprint), so you should be 616 feet behind the car in front. Here is chart I found. Of course, these are just averages, but they can give us an idea. The other thing that adds into the equation is the 'reaction time'. And as we all know, the older we get, the greater the 'reaction times' we have. So, according to this chart, if you equate a 'bus' to an RV, it takes, at 60 mph, about 60 feet or so farther to stop an RV than a car. So it would seem that we should allow about an extra 60-70 feet in our following distance to keep us safe. Of course at 70 or 75, the difference would be greater. In regards to 'reaction time', there are two parts. The first is the time that it takes for us to recognize the hazard. The average used for a 30 year old is 1.5 seconds. That is 132 feet at 88 feet/second. Then there is the gap of time that it takes the brakes to actually take hold. Studies show that is about .3 seconds, that is another 26 feet, then add on the 280 feet it takes to stop the rig, and you come up with a minimum of 438 feet under ideal circumstances, like you were totally on top of the situation, not sipping some coffee, or talking to your spouse, or looking in the mirror, or checking your speed. At 88 feet/second, distances add up in a hurry. As to the second comment of yours about what I said about MH manufacturers gearing the RV's so that the 'sweet spot' is at a place where it is above the speed limit, I stand by that. Your comment about being passed by the trucks in California, I agree completely. California could solve all their monetary woes just by enforcing the laws that already exist on the books concerning speeding on the freeways, and especially the "55 for all vehicles towing", and that goes for semi's as well as RVer's towing. Happy and Safe RVing. Share this post Link to post Share on other sites
roadster27 Report post Posted December 11, 2015 My ISC 8.3 ltr 330 hp Cummins and 3060 6 spd Allison , 27,000 lbs 40 ft single axle with 295 x 75 x 22.5 Toyo`s get 10.4 mpg at 60 @ 1650 rpm , and 10.8 at 55 @ 1475 rpm in 6th gear. Doesn`t matter if economy mode or not. Was measured early September for a week and ran the gen 4 hrs a day (about 2 gal day)-- Detroit to Jasper, Alberta, 2500 miles, lots of flats, some big hills in South Dakota , Montana Bev and Allen 99 AC 40TVS Share this post Link to post Share on other sites
paintedtugboat Report post Posted January 29, 2016 I can't understand what all the fuss is about MPG. Fuel prices have never been lower and my Freightliner LBCU tells me the MPG I am getting if I were interested. I can travel almost 900 miles with a full tank, why would I be worried about 0.02 MPG difference? I would much rather waste my energy popping open a cold one. Share this post Link to post Share on other sites
