i have a 2005 cummins with 3.73 gears and 48re. i consistently get around 12mpg. i'm not even towing but i do have a 900 pound dump box in the back. this hurts when fuel is $4.00 a gallon. Help!:dunno:
If you haven't already done it, there is a TSB out for the 2005 Cummins Rams concerning poor fuel economy. Take it in to your Dodge dealer and have them check if the update has been done, if not, it's a freebie. Other than that, there's a number of different things that can be done to improve fuel mileage. First thing is SLOW DOWN. The Cummins "sweet spot" for fuel economy is right around 1800-1900 RPM's. Basically, anything faster than 65mph, and fuel economy starts to go in the tank. Try different fuel brands. My truck can differ up to 4mpg from the fuel brand it likes (Cenex) to the one it hates. Also, if you live in cold climates, the "winter blend" of fuels is in the filling station tanks right now. I constantly see a 2-3 mpg drop using winter fuel compared to summer fuel. Go to Wal-Mart and pick up a bottle of Power Service diesel additive. 1 gallon costs around $17.00 and treats up to 300 gallons of fuel. The white bottle is for winter/anti gelling use and the grey bottle is for warmer weather. Put about 12 ozs into the tank every time you fill-up. This stuff is awesome and will turn the crappiest fuel into something special. It also counteracts the negative effects of the ULSD fuel we have to buy now. My truck sees a 2mpg increase using the additive, compared to not using it, no matter whose fuel I use. Other than that, it's just the regular stuff you hear. Run your tire pressure near maximum, don't carry any more weight than you have to, and though rather expensive at first, switching to all synthetic lubricants will help also.
Diesel-Dude hit it on the nail. Driving style and maintenance will have themost to do with it. The TSB is a good one to get, it sould help you out alot. As for the 900 lb dump box, no worries there, unless its 10 feet wide. Should not affect mileage that much.
I don't drive this thing hard at all. Barely ever drive it on the freeway, usually speed limit is 55mph where i drive. I did find that my tires aren't inflated enough though. How many more mpg will i see with the TSB done? Thanks guys.
I'm going to get the oil changed soon and i will see if I can get the TSB. On the last tank i saw just over 10mpg but i was towing a trailer. I just hope the TSB helps!
Diesel Dude has put a lot of thought into that reply and is spot on. The only other thing that I think might would help is to apply throttle and brake gently. Almost think of having an egg between your foot and the throttle pedal and the brake pedal. Try and avoid stopping. If you see a red light ahead slow down sooner and try not to stop at all. Using your momentum to accelarate again after the light turns green again. Good luck. LT.
This is all very good advice thus far. Diesel-Dude's post is very comprehensive and well thought-out, as are the other replies. Your tires being under-inflated alone can easily take economy down a couple MPG. I don't necessarily agree with running your tires at their max all the time, though. Granted, that's where you'll squeeze out the best fuel economy, but it also causes premature tire wear (tread gets worn down really quickly down the center). I think the small amount of added economy from running them over-inflated compared to running them where they should be would probably not be enough to offset the increased tire expense in the long run. Also, ride quality and handling can suffer a bit. While you want to make sure to keep your RPM's down, at the same time you need to be careful not to bog the engine. Revving a bit higher but staying on the turbo will help economy as compared to lugging the engine, as you're keeping the engine where it's most efficient. I'm assuming you've got fairly low mileage, in which case it's a good time to switch to synthetic lubricants all the way around. If you just run it in one area (say the engine) you probably won't get a noticeable improvement, but if used in all areas it can make a difference. If you've got higher mileage, I've got mixed feelings about swapping to synthetic. While I understand concerns over warranty, a lot of the upgrades available for your truck can give you really nice increases in economy. If you stay on the "milder" side of upgrading, most dealerships usually won't give you too much trouble over them.
Finally took the truck to the dealer. The TSB was already done but we found that the air filter was loaded with crap and i mean loaded! I think that will probably help cure my mileage problems. Thanks for the suggestions guys.
Guys help! More mileage woes. The first tank after we took it to the dealer was great, but the last two tanks have only taken me 350 miles:doah: We've noticed that the first half of the tank yields about 240 miles and the last half of the tank about 110 miles. What should i do. Should i keep hounding the dealer until it is fixed? I have the extended warranty, but it is only for the powertrain. will that cover mileage problems? The truck has 39,000 miles on it. Sorry guys but this is really frustrating.
keep on bugging them in a good manor and call chrysler financial/customer service and file a complaint about their product not the dealer....call chrysler evertime it has to go back to the shop for documentation......my new 07.5 cummins with 6800 miles has been sitting in the dealer right now for 2 1/2 weeks for a bad turbo....i blew a headgasket they tell me they are backed up cause all the newer 6.7s are coming in right now with the same problem.....the codes on the computer were low trans pressure and lost of boost....thats what the dealer said and they told me cummins says the fix is new turbo cause the internal waste gate acuator is bad and you have to replace whole thing.....well anyways hound the dealer and chrysler......
