I have an overkill tune with dod delete. You lose about 1-2 mpg but is well worth it. DOD is so annoying.

I kept my computers too. I just had him send me new ones so i always have a backup of both.

if there is anything you want to know ask. I am sure i could answer whatever questions you have about the tunes

 

quite a few people have reported a gain in mileage with dod off and the car tuned. i would be more concerned with the oil consumption issues dod causes than the way it makes the car sound. it does make the car sound like complete garbage though and was my main reason for tuning it out at the time.

i also dont know about this whole overdrive in the city deal. i dont really know how much fuel the op would save being in overdrive at 40 and under as opposed to being in third its not like the car has any gearing to it. with the 2.90s it has in it it seems silly to me to be in overdrive at all, but then again im used to driving 3spds with 3.70s-4.11s. i think the op should do a test of city driving with od vs no od and report his findings.

 

2mpg over the life of the car is pretty expensive though. Just for calculation sake, we'll throw out some numbers- say you start at 20 mpg and drop to 18 mpg.

Over 200k miles- that's 10,000 gallons of fuel at 20 mpg, and 11,111 gallons at 18 mpg- for a difference of about 1,111 gallons over the life of the car.

Multiply that by say an average of $3.75 per gallon (although this will likely be low, since I'm sure gas will go back up well above this, especially over the next 10 years, even with inflation factored in)- and that's a COST of $4200, plus the hundred or two for the tune to shut it off.

That's a pretty significant cost for just having better sounding exhaust under certain driving conditions.

Now, I could see if it was just a weekend car or something, but as a DD- that cost really adds up, even for only 2 mpg. I'd imagine the cost would be higher to someone who does more highway driving, and less to someone who does more city driving- but it was still just an example to show the cost beyond just the initial tune.

I've heard the claims too- even from people who didn't tune the car, and just got rid of DOD, and I honestly don't buy it. Just tuning the car alone can increase gas mileage, so why not leave DOD and just tune the car? Also, without very controlled conditions, it is hard to make an accurate assumptions about what the actual outcome is.

Only way I could see to definitively prove it would be maybe on a dyno or something where you could control virtually all of the conditions.

I can't see GM putting all the engineering time and extra costs into the cars if it had little to no affect on gas mileage.

Same as above- GM puts tons of hours into engineering and testing, even for their shift maps. If it was more economical to stay in 3rd at lower speeds- then the shift map would just be set up to not shift into OD and lock the converter until say 45, or 50 or whatever.

They have very specific reasons and testing to back up why the map was set up the way it was- and if they could've eeked a couple more mpg out by leaving in a lower gear at certain speeds, I'm sure that's what they would've done to boost the city mpg number on the window sticker.

 

if i didnt drive the way i do I could get 22-23 mpg...and that would actually be a gain from stock but I dont haha

 

X2... I have Will"s tune and love it... For the v8, just email him and he will give you the straight goods...

 

well if you do the math its about 1.25 a day for that 10 years. if 1.25 breaks the bank perhaps the op shouldnt have bought a v8 car. people spend more than that on coffee every morning. i think that price over ten years is well worth it to be rid of the sound of dod. dont get me wrong if i were driving cross country id have it on, but day to day its really not necessary. its not such a huge difference in fuel price to bother me.

you can also have it tuned to engage at a higher speed/rpm that way it would only engage on the highway. best of both worlds. you keep the dod for fuel mileage and dont sound like a total tool bag cruising around town.

oh and there was a write up on how to run dod on a toggle switch. it was on ls1 tech. this would turn dod on and off at the push of a button. no need for a tune and youd still have dod for those long highway drives. i wouldnt try it unless i was certain of my wiring skills.

also i thought dod only engaged in 4th gear, 35mph and above, 1/4 peddle, or less? i could be wrong on that. most of the time during city driving your not really cruising around at 1/4 peddle especially street light to street light.

 

LEW TUNE got rid of my DOD you need a tuner and get a hold of LEW here on the fourm

 

Any performace shop can tune that out. And they will give you a beter tune then tune in a can.

 

Thanks guys for all the input. Will get something done when the cash rolls in. I am not sure I have any performance shops around.

 

Same here and love it. I hated when the car went into dod mode never again.
You purchased a car with a V8 in it so thats what I want. if I want a 4 banger I would have purchased a car with a 4 banger!!