No F**king IDEA. Yes I have a lead foot, but 90% of the time is on cruise. I stay light most of the time, and still I get 5mpg. I knew I wasn't going to get 7 or 8 when I bought it, but geez...
Yesss... it's a Love/Hate affair... I hate it 90% of the time, thy en I get out and love the way she looks. It's like a really hot girlfriend that doesn't cook, clean, or work... if it wasn't for her screwing me, I'd have no reason to keep her around...
You may want to get the parameters changed on the ecm. Guy I talked to with a new 680 said it comes with 4 free ecm parameter changes.
You know what, I just remembered I had a small shop bump the #s up a little. I bet they screwed something up. Thanks for the reminder.
So update on an old thread.... 135k/5.6k on the clock. Added an APU 2 months ago, so I'm not idling. Switched to a stepdeck and saw an immediate bump of 0.5-1mpg. Was down for 3 days for emission(2nd time so far the 1pc unit has failed. 2 things I recently learned. Cummins dealer that did the emissions work said we are 2-3 years from possible having 5he DEF systems dropped completely. Its causing more problems than its solving( no #### right?) 3 different dealers have confirmed to stay away from the 525hp x15 performance series. Something with the factory timing, but every one they see has performance issues(emissions, fuel pressure, mpg, etc) 565s are the sweet spots for these new higher compression models. KW has 1.5 years to sort this crap out before I go back to a Volvo.
I cant say much for the fuel mileage as we are running around on 8 axles with an RGN. The truck is running great, no emissions issues whatsoever. The one thing that I keep seeing is it's running so much fuel through the filter that we have to change atleast the primary before the usual service interval. I'm running around 20k miles or less on an oil change. Once the filters gets some hours on them the pressure differential between the two will throw us into derate. We carry extra filters on board anyway and lately we've just started changing them out sooner rather than later. 605hp/2050tq. Big 18 with 3.73's and running around 140-160k most of the time. With a scraper on the back it shows a healthy 2 mpg but there is power to spare. I'll chime in again soon with another update, just over 70k on the odometer now.
