Its like when your wife gives you a choice between the black or red nightie ....... Its all good . We did run the generator while driving a lot on this trip, and don't know if the trip computer is incorrectly registering generator fuel consumption as Cummins fuel consumption (I doubt it sense the generator has its own fuel line right?) in many cases bad connection to motor. On hills I let the computer manage shifting. Then, when computing MPG, I remove that fuel burned from the total fuel burned (average .5 GPH for each). If you can't find a place for your RV-related comment elsewhere on the forums, then this is the place to post it. None better in my opinion. Does the extra weight fully explain the mpg difference (I do a lot of climbing out here)? Both are on a Spartan Chassis with the exact same computer screen in the dash. Share motorhome advice and have all your motorhome questions answered 24/7. Some of you may find my mileage hard to believe....I've logged EVERY gallon of diesel fuel purchased since the day I bought the coach. If we develop an engine problem will that be a serious problem? We also have a 4:88 rear gear so it has seemingly unlimited power and I do tend to use the power when needed. Accelerate faster, get better mileage, better horsepower, and more from our selection of upgrades for your Dodge Cummins Motorhome, from the 1993 to the 2009 model years. Never had the rig weighed. Powering You Through Life's Adventures Cummins and Onan have rich histories providing reliable stationary and mobile power around the world. Your mileage at 6.2 mpg may indicate a problem. I can only speak from my experience. An absolute worst-case scenario: Blowing the #1 turbo, which should be repaired by replacing both turbos and air-to-air cooler. With 24,000 miles the mileage is better than it was when new. The Revolution also seems to have a harder time going up the same hills. Thanks guys! I'm going to Jackson Hole in a couple weeks. They have all been done at Cummins Truck repair centers and most covered by warranty. 312.1K members. I DRIVE mine. But if the motorhome you find is a real deal make sure you have both the C9 and Allison computers revved to current levels and you should be fine. any way made the video by my cell phone so … I will have to do my own calculations and see what I get. ***** For me personally I would … More required hp means more fuel required. I tow a '07 Jeep Wrangler. This handbook is a general supplement to the more specific information contained in the operator manual that comes with every new Cummins generator. For example a 315 HP Cummins puts out 950 lbs torque where a 330 CAT only puts out 840 lbs of torque. Advantages the the Cummins are definitely the weight over the front axle when towing, exhaust brake, and power available at all RPMs. Hopefully the computer is a little off.... Mike, how hilly was your trip where you averaged 7.4? This is a cummins 8.3 350 the road relay 4 is showing this message" SID 237 active 3 engine controller subsystem ID # 237 unidentifiable. When I went from the Cummins 360ISC in my Phaeton, to the 400ISL in the Revolution, I was expecting similar mpg numbers. None of the repairs to my Cummins have been preformed at RV centers. As others have said anyone qualified to work on a Cummins can work on a Cat. The new Mercedes Benz Diesel Rotary engine is a tremendous option and will be available on the new Monaco roadmaster chassis by the new Monaco RV. It would be impossible to say one is better than the other without comparing specifics and even then each has comparable engines for size and weight coaches. The Diesel RV Club Technical Forum is an unofficial effort to enhance communication and exchange ideas and is open to anyone with an interest in Diesel Engines. I will do the math on paper and see how it compares to the computer screen and post back. Just for kicks....I have both a Cummin's and a CAT Service center near by.....I take my CAT to the Cummin's dealer with absolutely no problem or hesitation. I'm coming up on 40,000 miles on our ISL. I keep the speed around 58 because California is 55 towing. Rick, on a side note I must mention that I don't drive at 55-60 MPH either. Total miles is approaching 20k. In 2020, only 142 companies made the North American index over nearly two-dozen categories, ranging from automobiles to utilities. Towing a Suburban with the Phaeton, here in the Rockies, I would average 7.2mpg. I do think the gear ratio is different on the new coach. On flat land I use economy mode. Dodge debate. If you drive a Cummins-equipped RV with either the 5.9L, 6.7L, 8.3L or 8.9L engines, Parleys Diesel has you covered. For an outstanding reference on performance and MPG read the link below by Brett Wolfe. When I drove the Revolution from Minnesota to Utah with no toad, I got 6.8. I have the 6.7 ISB in our 34' HR and all I have to say about it is that it pushes the RV down the road plenty fast, did 16,000 miles between 6/2 and 12/16 with no problems and ran over all of the I-40 passes on the way home on the cruise control at 60, I-15 from Vegas also. RV Generator Handbook The RV Generator Handbook contains basic information that will allow you to use and maintain your new generator. The new coach is 6,000lbs heavier (36,000 vs 30,000). We have a Cat and it suits our needs. brakes were stuck at the start. Bob W. I've owned 3 Cummins, 1 Cat & 1 Mercedes. Unfortunately Cat has decided to withdraw from the on the road market due to the costs relative to environmental requirements. Parts and support are easily available. The information applies to any device pushed down the road with a diesel engine. Forums; RVing In Class . rdalcanto....Sometimes when I read mileage results I think the owner did his math on an abacus. The most popular heavy-duty engine in North America, the X15 is capable of powering premium motorhomes of any size with up to 605 hp and 1950 lb-ft of peak torque. Detroit Diesel / Mercedes Benz at 800-445-1980; Mercedes Benz Sprinter - 877-762-8267; Navistar at 331-332-5000; Click on Forum to view discussion topics. problems found in the actuator assembly. ´77 Dodge D400 Avion MH22 classic, restored aluminum motorhome. Looking at getting a MH and wondering how the 6.7L cummins with 340 HP preforms in the rocky mountains. WJOMullins. Also CAT has just announced they are no longer be in the OTR engine manufacture, all they'll make from now on are engines for heavy construction equipment. Whether I am loaded with 10k pounds of sand toys and trailer or just towing a 5k pound Jeep I generally have the cruise set at 67-68 MPH and run along with most OTR rigs. But, if you want to tow 12,000 lbs better get a 3500 if you want a Cummins or you will likely be overloaded. I wouldn't let engine manufacturer stop me if I found something I like. I have owned both and worked on both and would not let one dictate a purchase or not if you were comparing two similar coaches equally equiped. 8.3M posts. The fact that a motor home had one or the other wouldn't enter into my decision. Having driven both, I have to say I prefer the Cummins. Fail Mode" what does this mean? The payload is so low on a 2500 Cummins that the 2500 Hemi will usually out tow the diesel if you are concerned with being legal. How many miles do you have? I also do not have to contend with the western mountains. Well, if you would have followed all the sage engine advice on this site you would easily note that one is the finest diesel engine ever manufactured while the other is an absolute piece of junk...only trouble is that i can never remember which is which!!! Our ISL gets 7.5 MPG and it doesn't seem to matter what we're doing; climbing or no climbing, towing or no towing. Unlike Cummins, Cat is heavily invested in off road applications. I would avoid the Cat C9 engine since it was underpowered compared to the Cummins ISL and only used a couple years in motorhomes so they had trouble mating it with the Allison transmission. Getrag 5 speed, dual oil coolers, new clutch 1200 miles. Both are reliable engines with excellent histories. It will require some break-in if it is new. 58K on the odometer, 22,000 miles since complete restoration. Batteries at 12.8, disconnect switch power - Answered by a verified RV Mechanic Since I have hour meters on the generator and the Aqua Hot, I log their hours when I refuel. Gross weight is a big factor. This is like the old Ford vs. Chevy vs. your turbo problem is either caused by carbon buildup in. There isn't a dimes difference between Cummins and Cat. Funny...Cummins still makes diesel truck engines. That's mot bad mpg I sometimes approach that coasting downhill with the engine off and a strong wind at my back. No power to dash n ignition switch. Our current Motorhome has a Cummins. We have 41000 on ours and the average has been 8.8 mpg when adding all of the fuel purchases. The ISB XT carries forward many of … ... Cummins / Onan 6500 propane gen … Also compare rear end gear ratios. Of course I've found the perfect rig - with a CAT. While there are no motorhome dealers in WY that sell or service CAT's, there are plenty of truck service centers who can and will work on your CAT. If it takes X hp to move Y weight, then it will take X+ hp to move Y+ weight. Since I do most of my travels in and around the Rockies. a suggestion if and when you have your motorhome looked at. RV’s are the new source of income for dealers and they are happy too receive the new uneducated owners with open arms. The Banks Power option for this application is the PowerPack, which consists of … Kind of like asking whether a Ford or Chevy is better-- except there there ARE some models of each that are better/worse. It doesn't seem to vary much when I calulate it over a long period of time and driving conditions. Pick the rig that suits your intended use! Gives a more accurate picture of the actual MPG, which is low 8s. A year ago, I addded the VMSpc computer program and track trips by individual fill ups and overall trip mileage. Our engines and generators have led the way in reliable mobile power since mass production of RVs began in the 1960s – coming from our local manufacturing facilities in Minnesota and Indiana. Snidly; Nov 9, 2015; Replies 1 Views 1K. It's torque that gets you over the mountains.