Forum Discussion
- ib516Explorer III can feel it kick in and out, and with my Magnaflow exhaust, I can hear it now too.
- mtofell1Explorer
ib516 wrote:
Once up to operating temp, the 4 cyl mode cuts in all the time on my truck - everyday in fact, several times in a 8 mile commute. It kicks in when city driving as soon as I'm up to speed. On the hwy, as long as there is no wind and no hills, it's in 4 cyl mode. As soon as there's an uphill grade on the hwy, it kicks into 8 cyl mode, and it doesn't take much of a slope.
How do you know when it kicks in/out? I've never seen a light or anything in my Hemi 6.4. My wife's Honda Odyssey has a dummy light that comes on/off every time and it can go in/out every few seconds. I've never really thought too much about it on my truck but now am curious.
As for the mpg thing, starts/stops/idling does kill these things. I've also noticed the winter blend fuel in my area kills me by 1-2mps as a daily driver. Just pulled in tonight with a pretty good mix of hwy/city driving over the last couple weeks and I'm at 13.1 (still on winter fuel). I honestly don't even watch that closely. A 3/4 ton truck with a big gas engine 10 years ago got around 8-9 mpgs and 2 years ago gas about $2 more per gallon. Life with my truck is good :) - Buck50HDExplorer
ib516 wrote:
Buck50HD wrote:
In the last 5 months, I don't think I've driven my truck in any conditions where the cylinder deactivation would even come remotely close to activating. But, I don't haul groceries or commute with it. I also have not seen a direct comparison where there has been any significant difference in mileage between the 3. In fact, the 6.4 was consistently the worst in the PUT.com shootout. My 2004 2500HD 6 liter got the same mileage. There's a lot raving about the Ram mileage but I still have a hard time buying it.
I had a GM 5.3 with cyl deactivation and the only thing it did was cause stuck lifters on a cold start and sounded like it was coming apart. The mileage was no different than previous non-AFM 5.3's I owned. It was used to pass emission tests, not save fuel for the owner.
3/4-ton Shootout Fuel Economy
You must drive in some extreme conditions then. Once up to operating temp, the 4 cyl mode cuts in all the time on my truck - everyday in fact, several times in a 8 mile commute. It kicks in when city driving as soon as I'm up to speed. On the hwy, as long as there is no wind and no hills, it's in 4 cyl mode. As soon as there's an uphill grade on the hwy, it kicks into 8 cyl mode, and it doesn't take much of a slope. That said, here's a video of my hwy mpg. Why not post your hwy mpg? Surely, your 3.73s would have the advantage.
Here's a video of my truck's hwy mpg
I've seen your updates and I could make countless videos of 18+mpg cruising on flat ground in the summer. I've managed over 17mpg for an entire tank of gas so the steady-state highway cruising part of that was well over 18.
But, the reality is that as soon as I combine that with cold starts, warmups, idling(these things guzzle gas even at an idle), stop and go, short trips and towing, the lifetime average would not be dramatically improved with 1mpg better on the highway. That's what they proved at PUT.com.
BTW, in the same conditions as my 17.x mpg tank with the 6.2, my previous ecoboost netted 25.5mpg with non-ethanol fuel. And it towed a 9klb 5th wheel faster! Only slightly faster, so probably about as fast as a 6.4 Hemi:B - ib516Explorer II
Buck50HD wrote:
In the last 5 months, I don't think I've driven my truck in any conditions where the cylinder deactivation would even come remotely close to activating. But, I don't haul groceries or commute with it. I also have not seen a direct comparison where there has been any significant difference in mileage between the 3. In fact, the 6.4 was consistently the worst in the PUT.com shootout. My 2004 2500HD 6 liter got the same mileage. There's a lot raving about the Ram mileage but I still have a hard time buying it.
I had a GM 5.3 with cyl deactivation and the only thing it did was cause stuck lifters on a cold start and sounded like it was coming apart. The mileage was no different than previous non-AFM 5.3's I owned. It was used to pass emission tests, not save fuel for the owner.
3/4-ton Shootout Fuel Economy
You must drive in some extreme conditions then. Once up to operating temp, the 4 cyl mode cuts in all the time on my truck - everyday in fact, several times in a 8 mile commute. It kicks in when city driving as soon as I'm up to speed. On the hwy, as long as there is no wind and no hills, it's in 4 cyl mode. As soon as there's an uphill grade on the hwy, it kicks into 8 cyl mode, and it doesn't take much of a slope. That said, here's a video of my hwy mpg. Why not post your hwy mpg? Surely, your 3.73s would have the advantage.
Here's a video of my truck's hwy mpg - mowinExplorerI'm not sure how much the MDS increases the MPG's in my Ram, but it kicks in often. In the summer I was getting 18mpg highway unloaded, hand calc. Haven't been on a highway trip this winter, but I'm sure it would drop some do to the cold weather. I've got almost 19k on my 3500 SRW 6.4 3:73 gears. Only complaint is the stock tries suck. Only got 10k out of them.
- Buck50HDExplorerIn the last 5 months, I don't think I've driven my truck in any conditions where the cylinder deactivation would even come remotely close to activating. But, I don't haul groceries or commute with it. I also have not seen a direct comparison where there has been any significant difference in mileage between the 3. In fact, the 6.4 was consistently the worst in the PUT.com shootout. My 2004 2500HD 6 liter got the same mileage. There's a lot raving about the Ram mileage but I still have a hard time buying it.
I had a GM 5.3 with cyl deactivation and the only thing it did was cause stuck lifters on a cold start and sounded like it was coming apart. The mileage was no different than previous non-AFM 5.3's I owned. It was used to pass emission tests, not save fuel for the owner.
3/4-ton Shootout Fuel Economy - Need-A-VacationExplorerWe have a 2500HD over the 3500HD due to what was available off the lot, even with a dealer trade. We didn't want the factory nav, sunroof, etc or a diesel, and the very few 3500HD's on the lot that were a crew cab were loaded up to the gills!
IF I ordered one it would have been a 3500HD just for the extra payload for down the road. Plus, for the '13 & '14 trucks, a 3500HD was actually cheaper by a few hundred. Due to the hitch and tow mirros being an option on the 2500HD's. Not sure if this is still the same for the new '15 HD's. - mtofell1ExplorerThe cylinder deactivation and better mpgs was the #1 factor to purchase my 6.4 Hemi over the 6.2 Ford. I checked out message boards for both brands and around here and the Hemi seemed to be getting about 1-2 better. Lots of 13/14s with the Hemi and 11/12s with the Ford. I know there will be the guy with the Ford getting 16 who will chime in soon but I'm talking about just an average of as many real world experiences that I could find. Also, taking into account type of driving, towing, etc, etc.
Overall, you can't go wrong with any of the big 3 trucks. The change from my 8 year old Duramax to my Hemi is amazing. Just all the creature comforts and technology with these new trucks is great. - ib516Explorer II
labren wrote:
ib516 wrote:
Here's a much more comprehensive (and scientific/fair) test on video.
VIDEO
The reference is made many times about the HD trucks. When looking at the 2500 or the F250, are those considered HD trucks or is there something else has to be ordered?
No, they just mean 2500/250 class trucks. - kzspree320ExplorerGM and Ram both call their 2500 and up series Heavy Duty (HD). Ford calls its 250 and up series Super Duty. Different name same thing. In light truck naming 3/4 ton and up are called HD.
It gets confusing because those that really work with large trucks would call any truck one ton and less light duty.
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