After The Flash

[Sasquatch]

I'm scheduled to have my truck re-flashed at my local dealership on Tuesday, even though I've never had the first problem with my rig, and now have close to 9,000 miles on the clock.



My fuel mileage has been pretty good -- at least by comparison with what I'm reading here on these lists: I'm getting about 15. 5 in mixed around-town driving and about 17. 5 on the road, neutral wind, unloaded, and speedo set on 62 mph. Hauling a loaded, 16' enclosed trailer in the mountains, I'm getting about 9. 5 - 10. 5. I'm very pleased with these numbers, considering the truck is pretty much brand new and has only just begun to seat the valves.



What I'd like to know is this: What are the post-reflash benefits, if any, besides restoring the trucks that are breaking down to functional condition?



Have any of you noticed an improvement in mpg, beyond the average that everyone's reporting (14. 5 mpg overall)?



I'm anxious to have the re-flash done, because it seems to make good sense from a proactive, "preventive medicine" standpoint, but I'm also reminded of the old axiom, "If it ain't broke, don't fix it!"



Any advice from those who've had this procedure done (or those contemplating it, who're currently on the fence with me) would be much appreciated.



Of particular interest would be testimony from those to have noticed, post-reflash, either noticeably better fuel efficiency, or (heaven forbid) noticeably WORSE fuel efficiency.



Thanks in advance...

 

[Wolfy]

I'm scheduled to have my truck re-flashed at my local dealership on Tuesday, even though I've never had the first problem with my rig, and now have close to 9,000 miles on the clock.



What I'd like to know is this: What are the post-reflash benefits, if any, besides restoring the trucks that are breaking down to functional condition?



I'm anxious to have the re-flash done, because it seems to make good sense from a proactive, "preventive medicine" standpoint, but I'm also reminded of the old axiom, "If it ain't broke, don't fix it!"



Any advice from those who've had this procedure done (or those contemplating it, who're currently on the fence with me) would be much appreciated.

Hi Sasquatch,



Can't give you any "pre" report, since my truck had "the flash"(18-033-07 Rev. A) done before delivery.



I can give you this "post" info : My truck has performed flawlessly for over 1000 miles now, with only one noticed(by increased EGT) "Active Regeneration" event, at around the 1000 mile mark. I have had none of the other reported difficulties.



My milage is unreliable, as an "average", because I have only refilled twice, and have deliberately been varying my speeds to an unrealistic degree during break-in (all driving with no load, a good proportion in hilly country). Anyway, for what it's worth, the first tank hand-calculated to about 14. 8, and the second to 15. 1. The third I expect to be lower, because of increased percentage of around-town driving. (4WD, Dually, 3500, Quad, LB, Auto)



Frankly, I am expecting something satisfyingly-above 17 unloaded in the future.



Regarding fixing something "which aint broke", ... maybe the word "yet" should be part of the equation in this case.



I am confident that Cummins' engineers had a purpose for pujblishing this TSB, and it did NOT suggest that it was only for "troubled" trucks, ... despite the reported comments of some service departments.



Good luck,

 

[Jim Potteiger]

Sasquatch reply

Sasquatch, my truck was built around 5-15-07. I picked it up around 6-3-07. I drove it for approx. 600 miles with no trouble before having the reflash done. I notice you don't have a pyrometer and I would recommend having one. The pyrometer is the only way you know the truck is in a regen cycle. My exhaust temp. goes to 1200 degrees and stays there while in regen mode. I had the reflash done and have noticed no difference before and after the reflash. Mileage is still around 15-17 mpg running empty. Have not pulled camping trailer yet. Regen happens somewhere around 60-70 miles and last for approx. 10 minutes or 10-13 miles. Again, I see no difference in truck performance when in or out of regen except, as I said earlier the pyrometer goes to 1200 degrees while in regen. My truck has never shown a code. I don't believe you will see any difference after installing the reflash. Keep us posted. Thanks, Jim

 

[courierdog]

Where did you mount the Pyrometer for best monitoring of the Regen cycle and the EGT's

 

[Jim Potteiger]

Dave, I mounted the pyrometer along with the boost gauge on the driver side A pillar. Jim