LS4 Performance - Should i get rid of DOD

I am going to be having a tune dune by MonteSS8707 on Sunday, One idea ive been toying with is tuning out DOD. Ive heard mixed reviews to this. The negative side would be the loss of gas mileage. The plus sides would be less wear on the dod specific parts, and no more of the awful "helicopter" sound. I wouldnt mind getting rid of this but i would like your opinions first.

I personally don't feel DoD hurts the vehicles or causes any uneven wear, but that's just me.

What you have to do is ask yourself what you expect from the car and how you use it. For example I drove 527 miles to see my family, so the DoD was nice on the highway. I was getting 29 mpg as opposed to say 16 or 17 w/o DoD on. So that saved me a good chunk of change. On the other hand driving around Ann Arbor the DoD never gets a chance to click on, so it is worthless.

So where do you drive? Do you get a lot of benefit from the DoD due to highway driving, or are you more of a urban driver where the DoD isn't as useful? Assuming you see DoD click on a lot keep in mind reducing your fuel econ by 33% (more importantly, think of it this way, if you fill your tank 3 times every two weeks, you will now be filling it 4 times ever two weeks)? What else could you use that money for?

In the end I see no huge perfomance benefit to turning DoD off, it takes the vehicle .25 seconds to exit DoD mode. If I'm going to race I just rev the car a little right before I race and that rev clicks DoD off, and I'm good to go.

Your car, your call man.

I turn it off, because my shudders during decel and it SUCKS.

That was another thing i noticed, the car just shakes and rattles when in 4 cylinder mode. And i drive about 50/50 highway/small city.

Personally, I'd keep it. There is no benefit removing it.

I could not stand all the rattles and stuff so I got rid of it......i still get 26-28mpg on the highway....and right now with mostly city driving I am at 18.5 and I remote start the car every morning to warm up...it stays on till it shuts off.

ow, I must have a factory freak or something, because I never hear a rattle in DoD. Either that or the fact that my bass is at +6 and I listen to rap music must mean that my sound system is covering up my rattle (not to mention the hearing damage it likely causes). I'll have to turn my music off never time I'm on the freeway and see if I can hear and/or feel anything without the bass pounding away.

Same here, mine doesn't rattle at all.

Well the thing is it isnt DOD really that causes the rattle, i think its a wide open exhaust that i think it the culprit, when it goes into 4 cylinder mode its like riding down the highway with just the rear windows open. The parts listed are what i used on my exhaust and will give you an idea why, it is much louder that the magnaflow cat-back system. So i guess what im talking about really isnt a rattle, more of just an annoying exhaust sound. But i do love the way it sounds in v8 mode :)

CAT- http://www.jegs.com/webapp/wcs/stores/servlet/ProductDisplayPopup?storeId=10001&catalogId=10002&productId=750982&itemId=74426&langId=-1&showValue=1

Muffler(in the straight section) http://www.jegs.com/webapp/wcs/stores/servlet/ProductDisplayPopup?storeId=10001&catalogId=10002&productId=751040&itemId=411598&langId=-1&showValue=1

Tips http://www.jegs.com/webapp/wcs/stores/servlet/ProductDisplayPopup?storeId=10001&catalogId=10002&productId=744678&itemId=15862&langId=-1&showValue=1

How do you guys get these 20mpgs? I have no idea. I got 9.6 last tank but that included alot of warming up etc.

Well the thing is it isnt DOD really that causes the rattle, i think its a wide open exhaust that i think it the culprit, when it goes into 4 cylinder mode its like riding down the highway with just the rear windows open. The parts listed are what i used on my exhaust and will give you an idea why, it is much louder that the magnaflow cat-back system. So i guess what im talking about really isnt a rattle, more of just an annoying exhaust sound. But i do love the way it sounds in v8 mode :)

CAT- http://www.jegs.com/webapp/wcs/stores/servlet/ProductDisplayPopup?storeId=10001&catalogId=10002&productId=750982&itemId=74426&langId=-1&showValue=1

Muffler(in the straight section) http://www.jegs.com/webapp/wcs/stores/servlet/ProductDisplayPopup?storeId=10001&catalogId=10002&productId=751040&itemId=411598&langId=-1&showValue=1

Tips http://www.jegs.com/webapp/wcs/stores/servlet/ProductDisplayPopup?storeId=10001&catalogId=10002&productId=744678&itemId=15862&langId=-1&showValue=1

Yeah, I get like a bit of a raspy sound when I'm DoD mode coming out of the exhausts. I really can't hear it in the cabin though unless I open some windows up. You might have something a little lose. The other thing you can do is slip some sound muffling material in between the bottom of the passenger cabin and the exhausts.

Well i guess rattle was a bad word to use. Its not the sound of something loose.

How do you guys get these 20mpgs? I have no idea. I got 9.6 last tank but that included alot of warming up etc.

Cruise control. At least on my car DoD seems adverse to coming on unless I flick the cruise on. You also might have a gas hogging tune?

I don't do any highway driving where I could use cruise. I can get like mid teens if I try harder and want to freeze my ass off.

I would suggest to leave it on because there is no performance to be gained by removing it. You are up on the highway quite a bit from what u say so I'd keep it. I know how annoying the helicopter sound is and so does my fiance. But if it saves some gas, hell its worth it to me. More money for other mods or more gas to burn. I'd keep it, I've still got it on mine. But its whatever you want to do.

What MonteSS said
I feel the "vibration" at times in 4 cyl mode. perfectly normal when your exhaust is open or altered. Ahhhh the sacrafices we make! Buts its not anything thats annoying to me! So yeah I'll Keep it my friend,......

From someone who has actual experience w/ and w/o DOD. Go ahead and disable it. Most of my driving is city and I actually saw a slight improvement in MPG.

I think Lew saw an improvement also, w/o DOD.

I've always wondered something..

Does the exhaust note change with the cylinder deactivation? Does it go from a 4cyl buzz to the LS4's full eight cylinder rumble?

I've always wondered something..

Does the exhaust note change with the cylinder deactivation? Does it go from a 4cyl buzz to the LS4's full eight cylinder rumble?



EXACTLY this is what the guys are talking about when they are referring to rattle, Helicoptor, or vibration. It sounds very choppy in 4 cyl mode but only if you have some open exhaust, flows, flowmasters, deleted resy's, etc! :D

tune it out. i tuned mine out and never looked back. and my car averages over 19mpg and i drive mostly around town. the way i see it u didnt buy a 4cyl car, u bought a v8. and i dont know about u but i didnt buy a full-size v8 sedan for fuel economy anyway. if thats what u want buy a camry hybrid or something. just my 2 cents.

From someone who has actual experience w/ and w/o DOD. Go ahead and disable it. Most of my driving is city and I actually saw a slight improvement in MPG.

I think Lew saw an improvement also, w/o DOD.

yup yup...

disabled it... mileage went UP for me... by about 2 mpg...

all depends on your driving routine/habits tho...

I drive 60/40 city/highway... 75 miles a day....

and I'm averaging 20.5-21mpg....

whereas before, with the DOD on, I was getting about 18.5...


and the vibration the other guys are talking about is, if you're on a highway, and getting off an exit ramp... as you slow down, you'll feel the engine vibrating when it goes into 4 cyl mode as you brake/decelerate... if you take it out of drive and put it in 3rd to disable the DOD, it stops...

and if yours doesn't do it now, then just wait, it will... you probably don't have enough miles on your cars yet...

highly recommend having it disabled. I am so much happier with my car without it. No annoying vibrations, shitty exhaust noises, and the lifters dont make the noises alot if us have dealt with. Also DOD is only supposed to improve fuel economy by about 12%. With mine disabled my fuel mileage seems better around town and just a little lower on the highway.

Thanks for the input guys, these are the comments i was looking for.

How do you guys get these 20mpgs? I have no idea. I got 9.6 last tank but that included alot of warming up etc.

are you serious???? that is bad man...my f150 was getting 16, with twentys and huge tires......something is not right.

if your letting it warm up with the key in it then your avg mpg will drop alot because it sitting at 0mpg the whole time its warming up. when u start it with the electric start it doesnt affect it cuz the DIC is not on. But if your getting 9.6 you gotta be driving her pretty hard.

of course! i was upto like 60 in 1st merging on to the interstate in front of someone the other day. it might be like 15 this next time unless it gets cold again.

of course! i was upto like 60 in 1st merging on to the interstate in front of someone the other day. it might be like 15 this next time unless it gets cold again.

Lol....I drive her hard too. Gotta enjoy it ya know?

who DOESN'T like to "drive her hard" ??!! and hell yeah, you GOTTA enjoy it!!

:jest: :jest:

Drive it or park it, none of this grandma driving shit is allowed!

I went ahead and left DOD on for now, if i decide against it i might have it taken off on a later date. I cant believe the difference the tune made though. The car feels a good deal faster. Only thing left is springs/rockers/rods :).

I went ahead and left DOD on for now, if i decide against it i might have it taken off on a later date. I cant believe the difference the tune made though. The car feels a good deal faster. Only thing left is springs/rockers/rods :).

A 2 page thread just to leave DoD on? lulz.

I wanted to see how DOD was after the tune and honestly many of the negatives of it went away. I still want to disable it on a later date though. Really i dont think im actually in 4 cylinder mode much anyway.

Get rid of it. I have a a tune and went back and forth w/ turning dod on and off. After driving w/ out it, i dont want it back!

Thanks, i think i will have it removed at my next opportunity, i actually kept track of me highway 4cyl mode miles vs the miles i put on driving around town and im at about 25% highway so i think the gas mileage argument is out the window.