FWIW the wife’s vette does the same thing when you use the paddle shifters to downshift.
Range Technology Beta Testing
- Thread starter bruss
- Start date
securityguy
Well-known member
So much for a 100% solid solution
Well that’s interesting
Seems like they knew this was an anomaly, so they listed it as such. They clearly have limitations in what they can do with programming, so they brought forth what they could. I think this Global B electronic system is difficult to hack. That's why it's taking so long for tuning products to be available.
The only time I ever really know that DFM kicks in is at cruising speed on the highway and pulling up to the stoplight in D. I hear a bit of a gurgle in the exhaust note coming from my Magnaflow can when DFM kicks in. I didn't notice it much with the stock can on my 22. I can hardly hear the exhaust on my wife's 23 Tahoe, unless accelerating hard. I guess I'm about to find out what it does different on that rig.
Last edited:
Sounds like some things are getting lost in translation. What you're hearing when coasting to a stop is not the lifters de-activating from DFM. It's DFCO or Deceleration Fuel Cutoff where the engine isn't technically running under ignition and fires back off before stopping. You won't hear this running in L9 because engine braking is active in that mode.
Also worth noting when DFM is active oil pressure isn't cut to the lifter. On the contrary the solenoid allows pressurized oil to enter the bore at the point where it can act on the locking pin and de-act the lifter.
Also worth noting when DFM is active oil pressure isn't cut to the lifter. On the contrary the solenoid allows pressurized oil to enter the bore at the point where it can act on the locking pin and de-act the lifter.
JFC..........it's this guy's first post and he's already the smartest guy in this thread. Probably uses Mobil 1 too like the other smart guys.
It ain't compatible with snorkeled rigs either.
ChrisTX, ignore some of these dipchits, you sound like you're more onto this than anyone so far. anyone that thinks you need to spend time on a forum to know anything obviously doesn't know anything. so why does the oil pump control cut pressure in the deactivation then? another energy saving measure? do you agree stopping the deactivation should reduce lifter failure?
So I drove 280 miles today on a rural eastern OR highway with little traffic, lots of corners and lots of hills. there is a definite better throttle response, less downshifting , better compression holdback on hill descent, sounds better and I notice no symptoms of valve deactivation at any time. maybe there is, if so it's nothing worth mentioning.
None of this surprises me, what does surprise me is my fuel economy is 2/10 MPG better than it's ever been on the same trip. I'll have to see this play out over time before I'm going to say it helps the MPG, but I'm comfortable saying it's not going to make it noticeably lower.
So I drove 280 miles today on a rural eastern OR highway with little traffic, lots of corners and lots of hills. there is a definite better throttle response, less downshifting , better compression holdback on hill descent, sounds better and I notice no symptoms of valve deactivation at any time. maybe there is, if so it's nothing worth mentioning.
None of this surprises me, what does surprise me is my fuel economy is 2/10 MPG better than it's ever been on the same trip. I'll have to see this play out over time before I'm going to say it helps the MPG, but I'm comfortable saying it's not going to make it noticeably lower.
Sounds like you were running in L mode!
ZR TWO
New member
Thank you for this. If tech support at range knew this i wouldn't have been so confused.
securityguy
Well-known member
SGRACING
Well-known member
I'm absolutely sure that it was Mobile One causing the flutter in the exhaust tone!!Dipchits
In the 2024 when in sport mode the transmission seems to be reprogrammed. It acts like my Mercedes or the wifes Audi in sport mode when you’re pushing it. It holds gears and uses the engine for breaking. I do notice the truck gets quiet at very low speeds (under 30mph) and I think that’s the fuel being shut off or I would still be hearing popping and gurgling during deceleration like in the higher revs? This is with the active exhaust open in sport mode which I think gm did a fantastic job with. Better than any after market exhaust I’ve ever had. The sounds it makes between 4000 and 6000 rpm are musical. My favorite feature of the truck by far.
I agree, I think this exhaust sounds as good if not better than my TRX, I wouldn't change a thing on it. I leave it in sport mode all the time.
On deceleration it seems better, but still doesn't have the old school V8 sound to it, but it's not an old school V8 . I'm not sure the reason why, but I bought a V8 for acceleration not deceleration so I can live with it. it's like posi traction, nobody knows how it works it just does.
On deceleration it seems better, but still doesn't have the old school V8 sound to it, but it's not an old school V8 . I'm not sure the reason why, but I bought a V8 for acceleration not deceleration so I can live with it. it's like posi traction, nobody knows how it works it just does.
Silverado ZR2 Photos
Silverado ZR2 Photos
Most Member Reactions
-
564 -
532 -
231 -
200 -
199 -
161 -
154 -
139 -
80 -
77 -
76 -
70 -
62 -
60 -
59
Similar threads
