2004 CTD bad MPG

I just bought a chipper/shredder from a guy. He was driving a pretty nice and well-used 2004 Ram 2500 (edit:fixed) with the CTD. He was saying that the MPG had dropped down to 17 or so and he could not figure out why. Is there any well-known leading suspect?

Are you sure it’s a CTD? They didn’t put a diesel in a 1500

100% CTD. I think maybe it was a 2500. It was 2WD also.

Ok, 2500

Any codes showing, possible lift pump problem. Brakes hanging up. My 01 2500 would get 23-24 mpg on average unless I was towing.

In-town or highway? The '06 4x4 I had would run 16-18 city and 22-24 highway empty (depending on my right foot ). Of course, there were those that said I was dreaming and others that did about the same.


Tim

Also, the sweet spot when cruising the freeway in the 5.9 is around 2000 rpm. That’s about 70 mph. His 2wd most likely has 3.54s. Over 2000 rpm the mileage starts to drop.

My 02 2500 gets same mileage when empty, 23-24mpg. Mine is 6spd, 2wd . . . uhhh, is fuel filter clogged up ??

Thanks - I'll send over your thoughts to him. Much appreciated!

His 2wd most likely has 4:10. 3.73 was an option. No 3.54. The sweet spot is keeping it under 10 lbs. of boost.

I would look to see if the oil level is climbing. An indication that an injector is leaking fuel into the crankcase.

He can take the vin and run it at the dealer. That will give him the rear ratio. One thing he could do is start running a cleaner through the fuel. It may be a sticky injector. might take awhile. He could drain the fuel filter can, replace the filter and fill with cleaner. Then run the truck.

Check and make sure it doesn't have any boost leaks, it really hurts fuel mileage when you are just pumping air into the engine bay.

The ratio is printed on a sticker inside the glovebox. The fuel filter should be changed every other oil change. I pour the Lucas injector cleaner stuff through mine. Not 100% of the time. My truck seems to like it. I had an injector go bad and it sounded at times like the rods were coming out of it! No missing that one. I've seen the videos of them leaking into the valve train area but I never thought my trucks mileage was that bad to check it. Does this thing have an aftermarket air filter on it?

I agree on the fuel filter. I change it spring and fall. I fill the canister with a cleaner. 285k and running great, knock on wood!!

Dunno about an 02 but I definitely ordered my 01 6 speed 2wd with a 3.54. And my mileage empty at 60 mph is around 23-24 like others...70 MPH 2k rpm, stock tire size, stone stock motor. I'd say the sweet spot on my is around 1700 - 1800 / 60 - 65 mph, any above that and the mileage drops off.