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So I got the letter awhile back about the voluntary recall for the emissions system. So while it was in the shop they took care of it. Now the only problem my mpg dropped drastically. I use to get about 19-21 on the highway now I'm getting 15 if I'm lucky. Anyone else do this recall and have the same results?
 

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WHAT??? Making Emissions shit work will HURT performance??? :cookoo[1]:
Wow, I'm gonna have to make some calles to Al Gore.:rof
 

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Discussion Starter #4
only 15k more miles and it will all be gone:D but until then its just a pain in my ass
 

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yea emissions systems do not like mpgs at all
 

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So I got the letter awhile back about the voluntary recall for the emissions system. So while it was in the shop they took care of it. Now the only problem my mpg dropped drastically. I use to get about 19-21 on the highway now I'm getting 15 if I'm lucky. Anyone else do this recall and have the same results?
I had the same voluntary recall done about a month ago. Never had any issues with the DEF but thought i would do it anyway. I have noticed no drop in fuel economy after the flash. Get 19-21 empty and 13-15 towing 12,000lb trailer. 100% stock. And don't tell the 6.7L Cummins guys you are disappointed in 15 mpg, they would be happy as a pig in sh!t if they got that good of mileage stock.
 

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So I got the letter awhile back about the voluntary recall for the emissions system. So while it was in the shop they took care of it. Now the only problem my mpg dropped drastically. I use to get about 19-21 on the highway now I'm getting 15 if I'm lucky. Anyone else do this recall and have the same results?
Some are reporting improvement in mpg after the 'recall'.
 

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my mpg went down after i got the recall got done. ive been doing town driving mostly though. i gotta travel from new orleans back up to MA then MA to maine then Maine back to New Orleans so i will have plenty of time on the highway to let you know if i get the same, better or worse mpg. i no when i travled down from MA to nashville i was getting 19 mpg and this was before the recall.
 

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Discussion Starter #10
thanks for the input....i hope its only a phase and it will get better....now the big question is it worth deleting the def dpf and losing the warranty? I plan on having this truck for a long azz time and if taking that emissions equipment off will make it last that much longer I will take the chance of taking it off right now.
 

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thanks for the input....i hope its only a phase and it will get better....now the big question is it worth deleting the def dpf and losing the warranty? I plan on having this truck for a long azz time and if taking that emissions equipment off will make it last that much longer I will take the chance of taking it off right now.
I'm pretty sure that GM has done more long term durability testing on the engine/programming than any of the aftermarket 'delete' solutions providers could ever hope to do (# units tested x # miles tested etc)
 

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thanks for the input....i hope its only a phase and it will get better....now the big question is it worth deleting the def dpf and losing the warranty? I plan on having this truck for a long azz time and if taking that emissions equipment off will make it last that much longer I will take the chance of taking it off right now.
Since the lml has a 9th injector for adding diesel to dpf during regen and not in cylinder anymore, using DEF and way less egr, i am doing the opposite and staying competely stock for reliability. Modded trucks seem to be the ones with more self induced problems. These LML trucks run strong and clean and use very little egr, warranty is a nice thing to keep since the price of warranty is built into the purchase price of the truck.
 

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Since the lml has a 9th injector for adding diesel to dpf during regen and not in cylinder anymore, using DEF and way less egr, i am doing the opposite and staying competely stock for reliability. Modded trucks seem to be the ones with more self induced problems. These LML trucks run strong and clean and use very little egr, warranty is a nice thing to keep since the price of warranty is built into the purchase price of the truck.
I agree, this is the main reason why I have decided to go with the Duramax. So I don't have to delete all the emissions stuff. Otherwise, I would have gone with the Cummins and deleted it all off and have no warranty. Not sure about that. I can handle some soot issues with the DPF until they can be perfected a lot more. Time will tell how much soot the duramax will develope via the EGR. Can't be anywhere near he Cummings, and worst case can be deleted down the road. Most important thing for me was getting the regenerations out of the engine. Who in the world wants all that diesel fuel dumping into the crankcase. GM seems to have the best system for the emissions. It's chocking the Cummins to death. Does the EGR need a periodic cleaning like the Cummins. Haven't heard anything about that.
 

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Discussion Starter #14
thanks for all the good info might just do a dpf back exhaust cause i hate that tailpipe.
 

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I agree, this is the main reason why I have decided to go with the Duramax. So I don't have to delete all the emissions stuff. Otherwise, I would have gone with the Cummins and deleted it all off and have no warranty. Not sure about that. I can handle some soot issues with the DPF until they can be perfected a lot more. Time will tell how much soot the duramax will develope via the EGR. Can't be anywhere near he Cummings, and worst case can be deleted down the road. Most important thing for me was getting the regenerations out of the engine. Who in the world wants all that diesel fuel dumping into the crankcase. GM seems to have the best system for the emissions. It's chocking the Cummins to death. Does the EGR need a periodic cleaning like the Cummins. Haven't heard anything about that.
My last 2 Dmax trucks were stock, never had an EGR or Turbo cleaned due to soot, zero issues with them (except fotr my 2007.5 that had the heated washer fluid removal, recall). At 67,000 kms the 6.7L Cummins has a Turbo cleaning service and EGR clean service with CCV replacement, the Message will pop Maintenance required/See Dealer. This service is a $1500(average dealer cost) bill for the owner. Right now my uncles 2007.5 LMM has 220,000 miles and still original EGR and DPF and no turbo failure due to soot. The LML hardly uses any EGR( uses Urea insted), and is damn clean.
 

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My MPG went down also. I see about 16mpg on the highway traveling 72-74mph. I was seeing close to 18mpg all the time. :poke[1]:
 

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My MPG went down also. I see about 16mpg on the highway traveling 72-74mph. I was seeing close to 18mpg all the time. :poke[1]:
Ease up on that go pedal , nobody can keep up to ya :poke[1]::drink
 

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I guess, since we are the research for the manufacturers, they could be experimenting with the amount of regenerations required to keep the DPF clean and not clog up to point they need replacement. Of course, more regenerations will use more fuel. So, with the new flash that is being discussed, I wonder if that is the case and you are seeing more regenerations. Just an assumption on my part, but does make some sense though. Maybe someone else more knowledgeable can add to this. The reason the Cummins gets such bad mileage is probably due to the double whammy of both the NOx Absorber and the DFP that require regenerations.
 

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Having the Insight in my truck, i know exactly when and how long my regens are, and the distance travelled between regens. The truck regens the exact same amount as it did before the voluntary flash. The distance between regens is also the same as before 800-850 kms. As i stated before my mileage has been the same before and after updates. Just thought i would post this up since i have the capability to watch my regen from start to finish, as well as soot levels, post DPF temps, DPF pressure differentials, ect. Also knowing when your truck is about to go into regen( soot capacity level), helps me to plan a drive to get the best fuel economy when in regen and to do a full regen without stop and go traffic or any stops at all. Truck uses 3 liters of fuel to do a full regen, 50 km(30 miles) to do a full non stop regen. When truck goes into regen it will stop the regen if i slow down too much, stop for a light, then proceed again when speed and exhaust temp is appropriate to do so. By knowing when the regen starts helps with fuel economy by doing a full regen at hiway speeds. Stop and go traffic, stop at the store type driving causes regen to kick in and out, adding to worse economy.
 

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I honestly think I am just not going to have this recall done on mine.
 
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