So, I got my flash done this morning. WOW what a difference! Not only is the new powerband evident, along with the better-shifting transmission strategy, but my MPG went up a decent bit more than 2%

I use my "B" trip odometer on a per-tank basis. In combined highway/city driving, it was sitting right at about 17 with about 5 gallons left in the tank. It hadn't budged much since about 3/4 full. I drove about 50 miles (nearly all highway) and the mpg jumped all the way to 17.8. "Hmmm" I thought. could it be? just that last 50 miles enough to improve almost 1 full mpg?

I filled up 40 miles from home on the return trip and reset the trip (as usual). The LOM calculation on the return trip was... drum roll... 20.7! It estimated 2 gallons used in 41.5 miles. I went ahead and topped off just because I had to check it... and I put in 1.95 gallons. Holy crap... I hope it stays this way!

BTW, the truck now has 1200 miles on it, so some of the improvement is likely due to the engine breaking in a bit more. Who knows... but I'm dying to see what my average is for the commute next week

 

I'm tracking fuel usage with every fill-up. I'm reserving judgment until I see a trend which will be at least 3 tanks. I have to say though, I think you're right. Several indicators are showing an improvement. I'll know for sure in a couple of weeks.

 

two weeks from tomorrow I will be leaving for a trip to SC from TX. Then I"ll really get a handle on the highway MPG

 

I am glad to hear that the new flash is showing improvement in fuel economy. I won't see this improvement as my truck came with the flash so I will defer to the experts.

 

I just returned from a 300 mile jaunt with the fiver. Empty mileage is up around 1 mpg. Towing is up about .75 mpg. The performance improvement is much more noticeable while towing 13000 pounds. The truck stays in 6th gear much longer on any kind of uphill pull. I averaged 12.5 towing on the trip. I ran 125 miles empty after dropping the fiver off for dome service. 75 mph freeway netted 21.5 mpg.

Regards

 

I haven't towed yet on the new flash but I will in a couple of weeks. BTW - I noticed a regen message for the first time today. Orange screen flashed on the dash screen for maybe 5 seconds. It said "Cleaning exhaust filter" and my fuel economy plummeted for about 20 miles. I'm talking from 20-21mpg @ 70mph to about 14mpg. Is it normal for it to drop that drastically?

 

You're now a member of the "Holy Crap! What just happened to my mileage?" club. Congratulations.

Don't worry too much about it though. It's normal and over time doesn't really add up to much.

 

I have never seen mine drop more than 2mpg and after 10 minutes it is back to normal.

 

heh I need some contact info for that support group

good to hear it's normal... I guess I expected some drop in mileage since I think I have a handle on how the regen works... but 30% surprised me! At least it only lasted about 20 miles. Unfortunately, that was the majority of my commute this morning... I guess this tank won't be a good judge of post-flash MPG. Or maybe I'll just top off this afternoon and start fresh

 

Great info, guys!

Haven't made it into the dealer yet but I hope to sometime this week. At 2,200 miles I'm averaging between 20.5-21 MPG to and from work, which is all rural highway at 60 MPH or so. Would be nice to see 22!

 

Please keep a fuel mileage log and tell us how many gallons you put in it after 4,150 miles.

Thank you.

 

I have been planning to do that once the break-in period is over. Is 4150 the magic number?

 

I do alot pof highway driving, and all of mine so far is just hauling my butt around - I am seeing an average of 16-16.5 MPG if I dont do too much city driving - in the city it dumps to aprox 12-13...

 

how many miles? have you received the new flash yet? also, what gears in the rear?

 

No anywhere close to that will work, 41.5 miles really doesn't get anybody very much quality information "data". One hundred time that will start to show some good data.