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PonyKiller87
01-16-2009, 01:18 PM
Anyone know any details on displacement on demand? Does the engine have to come with it to have it or do some engines come with the parts and just aren't programed to do it?

I'm looking at getting a new colorado with the 5.3 V8 and Im wondering if its possible to get DOD on it. Sales guy at holtz says that its not a factory option but I though it might still be a possibility if its mainly just something in the computer.

Anakonda69
01-16-2009, 01:39 PM
wow kev your really set on this colorado thing huh? find your monster truck tickets?

Prince Valiant
01-16-2009, 01:46 PM
iirc, it uses a solenoid to change the oil pressure to a specific set of lifters...the lifters (which is likely specially designed vs standard lifters...don't know, haven't seen any from a DOD engine) can then collapse, keeping the valves closed.

I don't know if there are any block differences to allow for the channeling of oil to the specific set of lifters...and then on top of that, what lifter differences, and then, getting a computer to manage all this.

You're best bet is just drive a little more conservatively, inflate the tires a little more to 40 psi, keep overall speeds down another 5 mph compared to what you normally drive and then enjoy you're v8 colorado.

DOD does improve efficiency...but the 10%-20% you gain with it isn't worth the hassle and expense to retrofit it to an engine.

Tom has worked on both, so I'm sure he's seen if there are the differences in the block or what not.

It was interesting though...My buddy just learned his DOD didn't work at speeds above 70mph...so he slowed down. Keeping the speeds slower, which improves mileage anyways, and now the occassional help from DOD, he's gotten MUCH better mileage, lol. But the big thing was slowing down and not doing 80mph every chance he got, lol.

BAD LS1
01-16-2009, 02:21 PM
You would be in for one fuck story to install it. I have it on the monte and i shut it off months ago after the cam swap and then swap back to stock cam. It proved a marginal gain in MPG and it only worked good on straight, level roads other wise it was back to V8 mode. It BARELY works in fullsizes as the lack of torque in V4 is so overwhelming that it cant push a 5K lb truck along easily.

example: my monte's MPG with DOD avg about 24 with mixed drving
strictly V8 mode and optimized timing at cruise RPM's and TPS i get 22 mpg on avg.

FYI get your self HPT or something if you ge that coly, everything iseen on the new 5.3 powered colys are no quicker than the 3.7 powered units. As im sure its heavily dialed back for driveabilty.

PonyKiller87
01-16-2009, 02:22 PM
Yeah, I'm going to holtz after work to talk to the sales guy again and test drive some stuff to determin exacly what I want. When I was there last friday it was looking like I could get the colorado for slightly higher monthly payments than what I have on the s10. The thing pissing me off now is I want the suspension options stuff of the Z71 but I want the color matched grill and bumpers that the Z85 has. Both have the 5.3 available. The z71 has 4.10s and bigger tires and the z85 has 3.73s. So I guess its going to come down to driving it to see whats more important to me.

As far as the DOD goes, I wouldn't spend the time or money to retrofit the engine for it, but if its all there and its just a matter of turning it on or programming it into the computer then I would look into it.

Oh yeah I found the monster truck tickets, sitting on the table right where I left them. lol.

PonyKiller87
01-16-2009, 02:25 PM
You would be in for one fuck story to install it. I have it on the monte and i shut it off months ago after the cam swap and then swap back to stock cam. It proved a marginal gain in MPG and it only worked good on straight, level roads other wise it was back to V8 mode. It BARELY works in fullsizes as the lack of torque in V4 is so overwhelming that it cant push a 5K lb truck along easily.

example: my monte's MPG with DOD avg about 24 with mixed drving
strictly V8 mode and optimized timing at cruise RPM's and TPS i get 22 mpg on avg.

FYI get your self HPT or something if you ge that coly, everything iseen on the new 5.3 powered colys are no quicker than the 3.7 powered units. As im sure its heavily dialed back for driveabilty.


Good to know, I guess I never drove anything with the DOD. The idea sounds good but you know how that goes, sometimes its good on paper and sucks in reality.

I will be ordering HPT even if I don't get the coly so I can tune my other truck and the camaro. I read that in a few places that they Torque managment is set really high from the factory on the coly, most people turn it off completely and it wakes it up alot.

wrath
01-16-2009, 02:52 PM
Buy color matched bumpers and grill?

I don't think DoD is going to net you much on a truck.

Car Guy
01-16-2009, 04:10 PM
My one question is; how will GM's DOD perform when the odometer hits 100k miles or more...???

Anakonda69
01-16-2009, 04:24 PM
my truck has boost on demand. lol just get a d-max kevin and quit screwing around.

Prince Valiant
01-16-2009, 04:27 PM
My one question is; how will GM's DOD perform when the odometer hits 100k miles or more...???My guess is that as long as the solenoid is still working, and the correct oil is being used, it should, no prob.

(not sure if GM's requires specific oil grade...chrysler recommends 5-20W and 5-20W only if you wish DOD to work as designed)

Poncho
01-16-2009, 04:49 PM
All Gen IV GM V8s are provisioned for DoD, but not all use it.

PonyKiller87
01-16-2009, 04:49 PM
my truck has boost on demand. lol just get a d-max kevin and quit screwing around.

I like having a small crew cab for taking back and forth to work, and I already got the bitch, if things keep going well I may look for a truck like tylers in a year or two to use as a plow truck as the white truck becomes more of a toy. Damn I'm going to need to move to the country so I have room to park all this stuff, lol.

BAD LS1
01-16-2009, 05:44 PM
just forget the idea of DoD. Its marketed in such a way that it makes a GMT900 comparable to a ******* prius's hwy mpg with this great feature. I hate marketing scum bags. Its less than polished, sounds like a helicopter when active and switchs all the time like an old S blazer with a 700R4 between drive and OD At 45 mph.

The the oil supplies are in the valley but you would need the oil manifold, 8 special lifters, different cam, and wire harness. The Dod function just needs to be turned on in the E67 with afore mentioned components in place.

while its never a god idea to take away transmission torque managment, all of it in regards to the engine can be pitched and the biggy is the TM that has to do with the electronic throttle. A tune alone shaved nearly 1 sec off the monte's e/t and i still have 30% TM active for shifts. The TBSS is now a ******* animal after a tune, again all factory TM is in place sparing the 4L70 despite an upgraded corvette servo helping apply.

PonyKiller87
01-17-2009, 01:28 PM
just forget the idea of DoD. Its marketed in such a way that it makes a GMT900 comparable to a ******* prius's hwy mpg with this great feature. I hate marketing scum bags. Its less than polished, sounds like a helicopter when active and switchs all the time like an old S blazer with a 700R4 between drive and OD At 45 mph.

The the oil supplies are in the valley but you would need the oil manifold, 8 special lifters, different cam, and wire harness. The Dod function just needs to be turned on in the E67 with afore mentioned components in place.

while its never a god idea to take away transmission torque managment, all of it in regards to the engine can be pitched and the biggy is the TM that has to do with the electronic throttle. A tune alone shaved nearly 1 sec off the monte's e/t and i still have 30% TM active for shifts. The TBSS is now a ******* animal after a tune, again all factory TM is in place sparing the 4L70 despite an upgraded corvette servo helping apply.


Yeah, after hearing how it works I'm guessing DOD wouldnt like my driving style and wouldnt end up helping me much at all.

The coly isnt going to happen for a while now, couldn't come to an agreement on price and trade in value that I liked, so Im just going to stick it out with the s10 for a while.

Like I said I will be getting HPT either way to tune the plow truck and camaro. Ill probably hit you up for a little advice when I get to that point