anybody else's power and mileage gone down alot?

[Hammerhead]

Thanks for the tips guy's. I'll get to the dealer and see what they say. I need to get the CO2 recall done anyway.

 

[robobx]

mine's going back in to the dealer friday, hopefully they can figure something out

 

[Hammerhead]

I took my truck to the local diesel hot-rod shop and told him my symptoms. He said that something was wrong for sure and told me to take it to the dealership. I talked to the service manager who said he had a program update he could install that should fix it I hope this guy knows what he's talking about!!!I'll let you fellas know how it turns out. It goes in the shop on Monday morning.

 

[DragRacer]

I have 16000+ miles on my '03 now. It's a 2500 SLT QC, SO - 5 speed. Since about 12,000 miles I have noticed about a 4+ MPG loss of mileage on the highway. The computer also has gotten further off on avg. MPG. Used to be accurate to within . 5 MPG. Now it's off by 2+. I am still getting 18-19 MPG empty though. 22-24 MPG sure was nice while it lasted.



I also pulled the race car (about 6000 lb) to the track last weekend and the darn thing wouldn't get out of its way at highway speeds. It had no problem maintaining 70+ MPH. It just doesn't seem to have much acceleration for passing. From 60-70 MPH for example.



Fuel and air filter have been changed prior to the falloff.

 

[wyosteve]

Thanks guys. You're reinforcing my decision to keep my 01.

 

[Parshal]

I have around 20k now and have noticed a drop as well. I've added an Edge EZ with boost elbow, aFe filter in the stock box, westach combo gauge and the co2 flash recall. All these changes have taken place in the last 4k miles and I noticed the change about 2k miles ago.



I was reading through lots of posts here and someone mentioned maybe an intake leak. I called Geno's (where I bought the pier's type bolt and gauge) and one of the guys there said that on some trucks that have higher boost pressures sometimes the intercooler connectors start to leak. He suggested snugging up all the connectors. I'm going to do that as well as snug up the pier's type bolt. I'm going to run some BG 44k through the next tank, too, to see if that helps at all. That always seemed to do good things on my gassers.



Other than the above, I think I'll have to remove the EZ and boost elbow and run around a bit to see if mileage changed in a stock configuration.



I really don't want to deal with the dealer on this one.

 

[Maddey]

I posted this on another thread, but I recently brought my truck to the dealer because of very poor fuel mileage. The best mileage I have seen was 13. 5mpg hand calculated with the 9% difference added (I have 315s). That was before I towed my fifth wheel (9-10mpg). After towing a coulple of weekends ago, my mileage has dropped to an average 10-11mpg empty. The dealer did not find any codes and told me that they went ahead and reflashed the computer. I haven't driven enough yet to tell a difference, but will be towing this weekend, so we'll see. I did call the Cummins service line and they told me they could not work on the engine since they are supplying them to Dodge with no warranty. But, he did agree that there was a problem and I should be seeing much better mileage. Robobx and Hammerhead, let me know what your dealer finds out. Thanks.

 

[Parshal]

I just had a long conversation with the Assistant Service Manager at my dealer. I mentioned that my mileage had dropped and asked where to start looking. He said that, frankly, a 1 - 2 mpg drop is not anything that can be proven and that Dodge is not going to spend time looking for that. If it doesn't have a code it's not broken. He said that when they get flash updates to fix one problem Dodge has a habit of changing many things like timing, fueling, etc. He said he doesn't have any idea what Dodge changes with the flash updates either.



I asked him a hypothetical question in that if 100% of the owners who had their trucks re-flashed reported a 2 mpg drop what would Dodge do. He said probably nothing unless it were in the range of 5 - 6 mpg. He said Dodge calls 1 - 2 mpg insignificant. This guy was on my side of the issue but telling me the way he sees Dodge handling it.

 

[Prairie Dog]

Parshal, I appreciate it when they talk to me in a frank manner, even if the answere is "no", at least you know your not being B. S. 'd.

My drop in mileage started before I had C02 installed and I hate to say this but it started about the time I put the AFE in (now have the bullydog), but I can't see how that can be the prob.

 

[robobx]

mine started way before the reflash.

but on identical trips I'm getting 4+mpg less

on a trip from charlotte to the OBX last weekend towing an empty uhaul 6x12 trailer that weighs 1800# I got 18. 9 on the way out there, it's all flat, 350 miles. On the way back pulling the same trailer with a couch, washer, dryer, freezer and a few small things total weight may have been an additional 1500 but probably about 1000# I only got 14. 4 mpg... you mean to tell me an additional 1000# and a freezer sticking up 2 feet over the cab is gonna kill the mpg by 4. 5???

something isn't right.

 

[Mark_Kendrick]

I heard that there have been problems on trucks with boxes that ramp up fuel rail pressure causing problems with the overflow valve.



They report the same issues. . low mpg, power etc.



I wonder if a truck with stock pressures could have the same problem. The increased rail pressures are not supposed to be drastic. they may just be accelerating an existing problem.



Just a thought



FWIW,

Mark

 

[RedRam1]

robobx,



I'm a 2nd gen. guy, so my observations may not be entirely relevant, but on my truck, towing, even fairly light loads, does extract a pretty heafty fuel mileage toll.

My '01/5 HO gets around 20mpg highway mileage empty. When I pull my 17' bassboat - maybe 3500lbs, my mileage drops to right at 16, still not bad, but a solid 4mpg drop. My boat is probably more aerodynamic than your furnature, fridge, etc. so I am not surprised that you lost 4. 5mpg.

 

[Parshal]

Originally posted by Mark_Kendrick

I heard that there have been problems on trucks with boxes that ramp up fuel rail pressure causing problems with the overflow valve.

There was one person on the board that had a problem with the overflow valve but his truck quit running completely. It wouldn't even start. He had an Edge EZ.

 

[robobx]

Originally posted by RedRam1

robobx,



I'm a 2nd gen. guy, so my observations may not be entirely relevant, but on my truck, towing, even fairly light loads, does extract a pretty heafty fuel mileage toll.

My '01/5 HO gets around 20mpg highway mileage empty. When I pull my 17' bassboat - maybe 3500lbs, my mileage drops to right at 16, still not bad, but a solid 4mpg drop. My boat is probably more aerodynamic than your furnature, fridge, etc. so I am not surprised that you lost 4. 5mpg.

no, I lost another 4. 5 by adding 1000# and a freezer in the bed. the 18. 9 was towing the empty uhaul trailer. I was happy to get 18. 9 towing the empty trailer, that seems reasonable.

when the truck was new(less than 10,000 miles) I consistently got 23 on the highway and up to a high of 24. 4 on a 200+ mile trip mostly flat and running at 2000 rpm. Now even cruising at 55mph in 6th on the flats I'm lucky to hit anything over 20. 0 Hell I used to get over 20 in town... :{ :{ :{

dealer is going to look at it in the morning

 

[Hammerhead]

Just got my truck back from the dealership and they said" no problems found". Well i tried to tell them that the truck has lost power and mileage but they tried to convince me that it was that way all along. I did talk to the tech though and he has a bombed truck of his own and his recommendation was to go with a set of injectors to get more power and to leave the timing and fuel pressure alone. He said that as the truck breaks in it will get better, I guess only time will tell. Oh yeah, He also said to drive it like I stole it if I really wanted the truck to have good power. Said that the people who baby them seem to have more trouble and short life out of thier engine than the poeple who are ruthless and rod the sh*% out of them. Just thought I would pass that along

 

[MattSt]

Originally posted by Hammerhead

Oh yeah, He also said to drive it like I stole it if I really wanted the truck to have good power. Said that the people who baby them seem to have more trouble and short life out of their engine than the people who are ruthless and rod the sh*% out of them. Just thought I would pass that along

I get 15. 5 if I drive it hard, shift at red-line and make a nice dent in the carpet under the accelerator. 15. 0 or less if I drive like my grandma.



Don't quite understand it. Best I can figure is that this truck weighs so much and the boost comes on so late that it has to be driven hard to get into the sweet spot.



250 mile trip, ALL 65 mph cruise on- 16. 3 mpg. My old 01 would get 19-21.

 

[Steve M]

I'm right at 6,000 miles with mine with no loss in power or mileage. I'm getting 17-18 average around town. One traffic jam can knock it down to 16mpg. Interstate isn't too great with 4. 10s. It's about the same as in town if I run 70mph. 55mph nets 23mpg instant on the computer but 55mph is rare. Towing our 10,400 lb high profile 5th wheel gives 11. 5mpg at 65-68mph. Rolling hills call for some peddle to the floor but on all but the big ones I can maintain 68mph. This is farely consistant with my previous Dodge Cummins trucks.

The dealership I bought mine from now has a truck identical to mine but HO/6spd. It's very tempting but if I traded it would be for the novelty and icing on the cake. My SO/auto/4. 10 is adequate for our 5th wheel.

 

[Prairie Dog]

There may be light at the end of the tunnel folks. During my last tank of fuel my overhead, which has always been exactly 2MPG off, is now dead nuts perfect. My mileage has shot up about 2. 5 MPG. On the last tank i got 17. 7 and that included 65-70 mph on the freeway, stop & go and 200 miles of towing a 4500lb TT! During this period I basically drove it like I didn't care about mileage because of the towing.

In the past few months I got 15. 6 to 16 in my commute to work if I drove 65 - 70. I could get 18 if I kept it at 60.

I've got about 8k on her now and I'm thrilled!



Oo. Oo.

 

[jlord]

This is pretty weird. I have been pretty quiet on this issue, but I have had all of the symptoms that have been discussed on this thread. No loss of power really, but a 2-3 mpg loss.



But just like Praire Dog, my last fill up mileage was 18. 5! (calculated manually, the overhead said 16. 1) Which is pretty much where it was before I noticed it drop. I hope it stays there.

 

[Rosco]

Maybe the added mileage can be attributed to summer blend fuel coming back out.