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Her454
02-01-2006, 02:11 PM
I kinda have an idea but can someone explain in simple English the advantages of this (as in the new Dodge Trucks) and the how's and why's...??? It is simply for gas mileage?
Im looking at the 2006 GMC but I was reading about the new Dodge (I kinda like the look of them but still a diehard Chevy fan) and wanted some more info.....
Boatcop
02-01-2006, 02:27 PM
The cylinder de-activation is strictly to obtain better mileage.
When cruising at a steady speed, or decelerating, or going downhill, the onboard computer cuts fuel and spark to 2 or 4 cylinders (depending on the style). When needed for acceleration or going up hills, all 8 cylinders kick in.
I have that on my 2007 Tahoe, and the transition is seamless. You can't tell when it switches.
On a recent trip, the display read from 18 MPG in 8 cylinder mode to 36 MPG in 4 cylinder mode, going on a straight road with gradual dips.
Tom Brown
02-01-2006, 02:27 PM
Yes, it's simply about mileage. GM is using it again too.
GM was using it in the early 80s in their cadillacs but it didn't work out that great then. Apparently, the new systems are better... or so the manufacturers say.
I like the new Dodge stuff but I think GM gets better mileage without that than Dodge does with it.
Tom Brown
02-01-2006, 02:28 PM
...the onboard computer cuts fuel and spark...
... and compression, hence the reduced drag.
DansBlown73Nordic
02-01-2006, 02:30 PM
Back in the 80s those old Sleds would get stuck in the 4 cylinder mode on a hill. Everbody would have to get out and push!!!!!
Her454
02-01-2006, 02:31 PM
The cylinder de-activation is strictly to obtain better mileage.
I have that on my 2007 Tahoe, and the transition is seamless. You can't tell when it switches.
I guess that was my concern, since I hadnt driven one I wondered if you could feel anything when it switched back and forth or any power loss.....
Any opinions on either truck? I miss my GMC but Im starting to like the Dodge...
Jordy
02-01-2006, 02:51 PM
Any opinions on either truck? I miss my GMC but Im starting to like the Dodge...
Shirley, you can't be serious??? :D :D :D
Her454
02-01-2006, 03:02 PM
Shirley, you can't be serious??? :D :D :D
LOL, I just dont know if I can do it........ I've never owned anything else so I thought a change might do me good but....... :cry: :cry:
Froggystyle
02-01-2006, 03:04 PM
Shirley, you can't be serious??? :D :D :D
Of course she's serious... and don't call her Shirley.
Tom Brown
02-01-2006, 03:04 PM
I guess that was my concern, since I hadnt driven one I wondered if you could feel anything when it switched back and forth or any power loss.....
Dunno about the trucks but I've spent some time behind the wheels of the 300 and Magnum hemis and you can't tell. It's very smooth. The spec for cylinder reactivation is miliseconds.
Froggystyle
02-01-2006, 03:07 PM
Dunno about the trucks but I've spent some time behind the wheels of the 300 and Magnum hemis and you can't tell. It's very smooth. The spec for cylinder reactivation is miliseconds.
Since it works off of the Throttle Position Sensor (TPS) you can imagine that it would be as sensitive as your throttle.
Ziggy
02-01-2006, 03:13 PM
Strictly a fuel mileage advantage...GM has it again including my SAAB 97x (http://www.saabusa.com/saabjsp/97x/index.jsp) Sport Ute with the V8's...Thay call it DOD, Displacement On Demand.
I sure hope it works better than it did in the Caddies back in the 80's...that was a total crash/burn for 'em.
roostwear
02-01-2006, 03:14 PM
Actually the Dodge MDS system deactivates the lifters, not the injection. Transition time is 40 milliseconds.
Unforgiven
02-01-2006, 04:38 PM
I kinda have an idea but can someone explain in simple English the advantages of this (as in the new Dodge Trucks) and the how's and why's...??? It is simply for gas mileage?
Im looking at the 2006 GMC but I was reading about the new Dodge (I kinda like the look of them but still a diehard Chevy fan) and wanted some more info.....
Traci, for most people this system will work but for your driving style (on the mat) it might not work as well
SummitKarl
02-01-2006, 06:18 PM
T just break down spend the extra bucks by a powerstroke and be done with it.... :argue: they are very hard to ROLL :rolleyes:
Jbb
02-01-2006, 06:51 PM
Strictly a fuel mileage advantage...GM has it again including my SAAB 97x (http://www.saabusa.com/saabjsp/97x/index.jsp) Sport Ute with the V8's...Thay call it DOD, Displacement On Demand.
I sure hope it works better than it did in the Caddies back in the 80's...that was a total crash/burn for 'em.
I had one of them V-8-6-4 Caddies back in the 80's........nightmares....lol... :p
BajaMike
02-01-2006, 07:03 PM
I don't like it...seems like there would be drag...and 4 cylinders working harder....
And reduced lubrication to the cylinders....:confused:
Just lighten up on the pedal...sounds like a gimmick to me.
:skull:
Boatcop
02-02-2006, 05:35 AM
And reduced lubrication to the cylinders....
Shouldn't be an issue. The fuel doesn't do anything for lubrication.
Unless you've got one of those 2 stroke Suzukis.
I had one of them V-8-6-4 Caddies back in the 80's........nightmares....lol...
I think the technology is a little more advanced nowadays, than 20 years ago.