How much better is the 14-15 6.2 vs the old one
09-22-2015, 03:30 PM
#11
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[QUOTE=rijrunr;5313273]
I had a 2010 and now a 2014. Both had the max trailer. I really like 373's. My 14 has a little more power stock than the 2010. I had LT's on the 2010 and that helped a lot. I have shorties on my 14 and there is a little improvement, but not like the LT's. I just installed 150 shot of NOS. I predict it will take out the transmission if i dont go easy on it. Lost the transmission on the 2010.
How do you think they compare, is the 2014 a 6 speed??
I had a 2010 and now a 2014. Both had the max trailer. I really like 373's. My 14 has a little more power stock than the 2010. I had LT's on the 2010 and that helped a lot. I have shorties on my 14 and there is a little improvement, but not like the LT's. I just installed 150 shot of NOS. I predict it will take out the transmission if i dont go easy on it. Lost the transmission on the 2010.
How do you think they compare, is the 2014 a 6 speed??
09-22-2015, 03:37 PM
#12
That could well be, wot in a 1/4 mile.
But as a daily driver, the tranny and gear ratios make it feel lazy and unresponsive to throttle input.
It is never in the right gear or rpm range to get up and go like a 6 speed would, as a d/d.
That is my experience, others may vary.
I haven't tuned mine yet, but as I said above, you can't tune out the number of gears and final drive ratio, it is what it is.
To my mind, having had numerous tuned trucks, having the tranny do what it should when you want it to
is just as important as making more power.
It's not like I don't like the my truck, just that the same engine with a 6 speed and 3.73's and a good tune would rip a whole lot better.
But as a daily driver, the tranny and gear ratios make it feel lazy and unresponsive to throttle input.
It is never in the right gear or rpm range to get up and go like a 6 speed would, as a d/d.
That is my experience, others may vary.
I haven't tuned mine yet, but as I said above, you can't tune out the number of gears and final drive ratio, it is what it is.
To my mind, having had numerous tuned trucks, having the tranny do what it should when you want it to
is just as important as making more power.
It's not like I don't like the my truck, just that the same engine with a 6 speed and 3.73's and a good tune would rip a whole lot better.
09-22-2015, 10:04 PM
#13
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Well if you look at the ratios compared to the 6 speed there is much less rpm drop between gears. Steeper 1st gear with 3.23s than the 6 speed with 3.42s by far and less rpm drop in every gear. The ZO6 has the same 8 speed as the trucks (more of less) and that is the fastest shifting tranny out there. Its just the tune on the trucks!!! The tune will be available in time.
09-22-2015, 10:35 PM
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Like I said, it's HP or MPG.
There are some cool attributes though.
Running about 70 mph, the thing is barely above 1800 rpm.
It is so smooth and quiet on the highway, I am always going way faster than I think, 75-80 feels like 60.
Cruising around town, same deal, very low rpm for given road speed.
I put the Magnaflow 3.5 inch cat back on it and it is perfect. Hear it when you want, barely hear it at a constant speed.
MPG is 3-4 better than the 2010 6.2
I also did a 2/3 drop, same as what I did on the 2010.
The 2015 has Ranchos, they are softer at first compression but hit harder at full compression, the 2010 max pack had better
suspension. Never harsh.
I tow the same 7000 boat and trailer. Sorry, 6 speed towed way better.
You need to question GM's thought process.
Why would people buy a 6.2.......
Not for better mpg,
They would buy a 6.2 for better power and or better towing.
The 8 speed diminishes both those criteria.
If you want get up and go, find a 2014 6.2 6 speed.
I would trade even for one if I could find one.
IMHO
Last edited by Allgonoshow; 09-22-2015 at 10:49 PM.
09-22-2015, 10:48 PM
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Well if you look at the ratios compared to the 6 speed there is much less rpm drop between gears. Steeper 1st gear with 3.23s than the 6 speed with 3.42s by far and less rpm drop in every gear. The ZO6 has the same 8 speed as the trucks (more of less) and that is the fastest shifting tranny out there. Its just the tune on the trucks!!! The tune will be available in time.
You need to separate wot performance and aggressive daily driving.
There is more to it than quick shifting for d/d.
I am not trying to crap on the truck, but stating facts from my own experience.
09-25-2015, 02:11 PM
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Take this for a grain of salt, my buddy has the denali with the 8 speed and the Z06 with the 8 speed. he said the 8 speed in the Z06 feels light years ahead of the truck. to him, the 8 speed feels lazy and a bit sloppy and sometimes confused. Like others have said, he and I agreed it has a lot to do with the tuning which will get better with time, but think about the 6 speed when it first came out. There were a lot of complaints and now it's arguably one of GM's better transmissions out there. I would assume the next model year would be better tuned than what is out there now, but i could be entirely wrong.
For the increased gas mileage, I would personally go with the 8 speed, but I drive a ton and have a Camaro for when i want to go fast. The 8 speed's tow rating is over 12,000 pounds now and 14 seconds for a have truck in the 1/4 mile is no slouch.
I bought a 15' 5.3 with the 6 speed which I love over my 4.8/4 speed sierra but if funds were available, the 8 speed wouldn't have even been a question to me. Tune only 6.2 8 speed running 13's doesn't sound too bad to me if you have the cash.
For the increased gas mileage, I would personally go with the 8 speed, but I drive a ton and have a Camaro for when i want to go fast. The 8 speed's tow rating is over 12,000 pounds now and 14 seconds for a have truck in the 1/4 mile is no slouch.
I bought a 15' 5.3 with the 6 speed which I love over my 4.8/4 speed sierra but if funds were available, the 8 speed wouldn't have even been a question to me. Tune only 6.2 8 speed running 13's doesn't sound too bad to me if you have the cash.
09-26-2015, 02:13 AM
#18
On The Tree
[QUOTE=Allgonoshow;5313391]My 2014 is a 6 speed with 373's. I test drove one with 342's and to me it was night and day. I didnt look at the 342's any further. I have not driven the 8 speed. At a 75-80 cruise, I am at 2,200 RPM, I am averaging 19 mpg in the mountains. Compare that to my 2006 6.0L 2500 that got 11 mpg towing ir not. I'll never own a 5.3 or 6.0 again.
Last edited by rijrunr; 09-26-2015 at 02:19 AM.
11-15-2015, 10:00 AM
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I can add to this post. I have an early 2015 Sierra Denali with the 6.2/8spd/3.23 package. Got it in January and I now have 42,000 miles.
When I first got it, the trans shifted awesome! Don't get me wrong, it wasn't a corvette, but let's be honest it's not meant to be. That said, the shift points, how long it held gears at a given load, etc was really good---basically it felt like it was in its powerband for a given gear most all of the time.
I was getting some intermittent clunks at slow speeds/light on/off throttle due to downshifts and I seen that GM had some reflashes out for the transmission. Figured that the shifting/tcc schedule would be refined even better so I had the dealer reflash it. Big mistake!!! Didn't cure the intermittent clunks and now it often feels laggy (in too high of a gear and takes too much throttle input to get it to downshift). I've had it reflashed twice iirc and it still sucks! Plus clunks or getting worse. GM says its normal driveline backlash.....that's another story....
Anyways, a good tune I'm sure will make this truck feel 50% more powerful (being in right gear while cruising around).
Mileage is amazing. I have a lifetime mileage of 17.4 (2000 miles of that towing 7000lbs at 70-80mph plus some intermittent towing around city). My DIC display shows average mph at 34mph. If I rag on it, I'm in the high 15-17 range. If I drive it normal, the 17.5-18.5 range. If I drive like I have an egg under the pedal (and in summer), I get 19-20. On hwy, I see 21-22 at 70mph. 22-23.8 at 60-65mph. Higher speeds, it drops substantially quicker---19-20 range doing 75-90 (in mexico of course).
I went 13.77 at 99mph yesterday in mid 40 temps/50% humidity with 1.935 60 foot. Best 60 foot yesterday was 1.91. In 60-65 degree temps, it went 14.06 at 97.
Race weight is 6000lbs. Truck weighs 5700 (verified on scales at local truck stop).
Overall, great package from GM and will be even better with some bolts on and tune!
I say get it!!! Good luck.
When I first got it, the trans shifted awesome! Don't get me wrong, it wasn't a corvette, but let's be honest it's not meant to be. That said, the shift points, how long it held gears at a given load, etc was really good---basically it felt like it was in its powerband for a given gear most all of the time.
I was getting some intermittent clunks at slow speeds/light on/off throttle due to downshifts and I seen that GM had some reflashes out for the transmission. Figured that the shifting/tcc schedule would be refined even better so I had the dealer reflash it. Big mistake!!! Didn't cure the intermittent clunks and now it often feels laggy (in too high of a gear and takes too much throttle input to get it to downshift). I've had it reflashed twice iirc and it still sucks! Plus clunks or getting worse. GM says its normal driveline backlash.....that's another story....
Anyways, a good tune I'm sure will make this truck feel 50% more powerful (being in right gear while cruising around).
Mileage is amazing. I have a lifetime mileage of 17.4 (2000 miles of that towing 7000lbs at 70-80mph plus some intermittent towing around city). My DIC display shows average mph at 34mph. If I rag on it, I'm in the high 15-17 range. If I drive it normal, the 17.5-18.5 range. If I drive like I have an egg under the pedal (and in summer), I get 19-20. On hwy, I see 21-22 at 70mph. 22-23.8 at 60-65mph. Higher speeds, it drops substantially quicker---19-20 range doing 75-90 (in mexico of course).
I went 13.77 at 99mph yesterday in mid 40 temps/50% humidity with 1.935 60 foot. Best 60 foot yesterday was 1.91. In 60-65 degree temps, it went 14.06 at 97.
Race weight is 6000lbs. Truck weighs 5700 (verified on scales at local truck stop).
Overall, great package from GM and will be even better with some bolts on and tune!
I say get it!!! Good luck.
11-16-2015, 12:12 AM
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I have a 15 6.2 with the 8speed. CC reg. bed. I really don't know what some of you guys are talking about. I've owned fast LS powered cars, and driven all types of large trucks. For what it is the 6.2 8 speed is an awesome powertrain. It's not just mileage, the performance is fantastic for a truck, bone stock. 13.77 1/4mi with a 6000 pound race wieght is not low performance by any stretch off the showroom floor. I hit 27.7 MGP on a long roadtrip with the 6.2. My mostly in traffic lifetime is 16.7 and will improve with a few mods. (Truck is new still) It seems to shift much better with the TC off to me. No, it's not going to have diesel like towing performance, and that should not be expected & it's not a vette. But for somewhere in between, is pretty impressive to me. I guess I don't know anything. Not starting an internet fight. I really like mine, & in coming months the tuning will be figured out & what mods work. The overall rifinement is nice, I don't know what is better on the market right now(subjective I know). I could have bought any truck, & choose specifically the 6.2 8 speed after much research, and am not dissapointed one bit.