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There was a post a while back made by someone who had a friend working at a dealership. They claimed to install an 'experimental' update into his TCM to fix the sloppy shifting. After reading the posts, it seems that his truck had actually been tuned and it wasn't a GM update/fix.How are you guys liking the new 8-speed?
Are they still not shifting properly? Any other complaints? And was there an actual GM update put out to take care of things?Going to look at a few different 6.2L's this weekend, don't plan on buying but would like to know how they are working out 'just in case' I decide to bring one of these new trucks home. Looking at the Sierra Denali, a couple Sierra SLT's, Silverado High Country, and some LTZ's with the 6.2L engine.What's the verdict on that combination from those of you who have owned one for a while now?Sent from my crappy iPhone 6using Tapatalk. I have 15 denali 6.2 8speed and I love it.
Allison 1000. Initially the Allison 1000 was a 5 speed transmission, rated to handle up to 620 lbft (841 Nm) of torque. A new 'Generation 4' 1000 was introduced in 2005 that added a 6th gear at the very top of the ratio ladder, making it a double-overdrive.For the 2006 model year, manual gear selection was introduced. Allison Transmission (NYSE: ALSN) is the world's largest manufacturer of fully automatic transmissions for medium- and heavy-duty commercial vehicles and is.
There have been some minor (what I call minor) issues where it sometimes flares but after the update it has been good. I never had a newer 6sp but I came from an 04 Sierra Denali and the 8sp is night and day difference.
It is great for driving around town and it is even better towing. Not sure what some one couldn't like about it, besides them just saying they don't like it. Has it been 100 perfect no, but it has been great. Def an improvement after the tsb/recalls gm performed. Towing my boat up the passes was awesome with 6.2 8sp combo, felt like it was always in the right gear and right rpmowned mine since march and over 6k miles, got my vote for sure.
Ordered mine and took delivery in May. 2900 miles so far and I love it. I came from a 2007 5.3 with 4 speed that had huge gaps between gears. This new 8 speed is different but mostly in the best ways. The 1-2 shift is the only gap under light throttle but smooth and unnoticeable after that. Get on it and it will hammer through gears. Towing is fanatic as others have said.
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Don't take a few folks negativity to draw your conclusion. They tend to post more than the positive ones.Sent from my SAMSUNG-SM-G890A using Tapatalk. I've had a '14 w/ 5.3 and 6 speed and now a '15 w/ 6.2 and 8 speed, the combination of the throttle tip in plus the behavior/programming of the tranny actually makes the 5.3 truck feel more powerful just putting around town.
Unless you really mash the pedal on the 6.2 it's tough to get it into the meat of the torque curve and with 2 more gears it's tough to drive @ 1/2 throttle and hold a gear it always wants to upshift- essentially it turns the power delivery into an on/off situation- I hate it.The feeling of what seems to be the torque converter/clutch pack or whatever disengaging then abruptly re engaging when going from coasting to light throttle is maddening- feels like you're doing damage to the truck. I had a g8 gt w/ the 6L80 and it exhibited similar behavior before I had it custom tuned- once tuned it was an entirely different car- I'm sure the same can be said for the new 8 speed. I did notice after going through the adaptive 'learning' process the 6L80 6 speed in my 14 truck was better than the one in my 08 G8.I'm sure the tranny software has been improved on since back in '07After tuning these trannies you should be able to determine exactly how much throttle effort will result in however many gear up shifts or downshifts you are tying to achieve - on a custom tuned auto a slight upward movement from your right foot results in a 1 gear up shift.a 1/4' of travel or so back down & u get a perfectly timed downshift etc. You will be able to 'feel' the shifts more as well.but not in a bad or intrusive manner.I think a lot of this programming that seems annoying is done to 'preserve' the tranny although it seems like it's doing damage to me and also more so to enhance gas mileage.I will be getting my truck tuned in the very near future- I can attest 100% coming from a 6 speed 5.3 2014 w/ 3.42s that the 8 speed tranny in my 2015 pretty much negates the pleasure/advantage of the 6.2 engine. It's been a wash from my experience Edited August 31, 2015 by crushNchowda. I've had a '14 w/ 5.3 and 6 speed and now a '15 w/ 6.2 and 8 speed, the combination of the throttle tip in plus the behavior/programming of the tranny actually makes the 5.3 truck feel more powerful just putting around town.
Unless you really mash the pedal on the 6.2 it's tough to get it into the meat of the torque curve and with 2 more gears it's tough to drive @ 1/2 throttle and hold a gear it always wants to upshift- essentially it turns the power delivery into an on/off situation- I hate it.The feeling of what seems to be the torque converter/clutch pack or whatever disengaging then abruptly re engaging when going from coasting to light throttle is maddening- feels like you're doing damage to the truck. I had a g8 gt w/ the 6L80 and it exhibited similar behavior before I had it custom tuned- once tuned it was an entirely different car- I'm sure the same can be said for the new 8 speed. I did notice after going through the adaptive 'learning' process the 6L80 6 speed in my 14 truck was better than the one in my 08 G8.I'm sure the tranny software has been improved on since back in '07After tuning these trannies you should be able to determine exactly how much throttle effort will result in however many gear up shifts or downshifts you are tying to achieve - on a custom tuned auto a slight upward movement from your right foot results in a 1 gear up shift.a 1/4' of travel or so back down & u get a perfectly timed downshift etc. You will be able to 'feel' the shifts more as well.but not in a bad or intrusive manner.I think a lot of this programming that seems annoying is done to 'preserve' the tranny although it seems like it's doing damage to me and also more so to enhance gas mileage.I will be getting my truck tuned in the very near future- I can attest 100% coming from a 6 speed 5.3 2014 w/ 3.42s that the 8 speed tranny in my 2015 pretty much negates the pleasure/advantage of the 6.2 engine.
It's been a wash from my experienceWow, this is exactly how I felt when I first had my 5.3/6spd with 3.42's. Shame that some still experiencing this on the newer 6.2/8spd. I still think GM gimped these new trucks to achieve higher MPG ratings. I've had a '14 w/ 5.3 and 6 speed and now a '15 w/ 6.2 and 8 speed, the combination of the throttle tip in plus the behavior/programming of the tranny actually makes the 5.3 truck feel more powerful just putting around town. Unless you really mash the pedal on the 6.2 it's tough to get it into the meat of the torque curve and with 2 more gears it's tough to drive @ 1/2 throttle and hold a gear it always wants to upshift- essentially it turns the power delivery into an on/off situation- I hate it.The feeling of what seems to be the torque converter/clutch pack or whatever disengaging then abruptly re engaging when going from coasting to light throttle is maddening- feels like you're doing damage to the truck. I had a g8 gt w/ the 6L80 and it exhibited similar behavior before I had it custom tuned- once tuned it was an entirely different car- I'm sure the same can be said for the new 8 speed. I did notice after going through the adaptive 'learning' process the 6L80 6 speed in my 14 truck was better than the one in my 08 G8.I'm sure the tranny software has been improved on since back in '07After tuning these trannies you should be able to determine exactly how much throttle effort will result in however many gear up shifts or downshifts you are tying to achieve - on a custom tuned auto a slight upward movement from your right foot results in a 1 gear up shift.a 1/4' of travel or so back down & u get a perfectly timed downshift etc.
You will be able to 'feel' the shifts more as well.but not in a bad or intrusive manner.I think a lot of this programming that seems annoying is done to 'preserve' the tranny although it seems like it's doing damage to me and also more so to enhance gas mileage.I will be getting my truck tuned in the very near future- I can attest 100% coming from a 6 speed 5.3 2014 w/ 3.42s that the 8 speed tranny in my 2015 pretty much negates the pleasure/advantage of the 6.2 engine. It's been a wash from my experienceI can agree. I actually drove a 2015 6.2L 8 speed Denali on Friday. I was toying with the idea of trading up because I got a letter from my dealer saying they wanted to buy my truck. While the 2015 8 spd 6.2L 3.23 felt good. I didn't feel like it was THAT much better than my tuned 6 spd 2014 5.3L 3.42.I really couldn't justify the cost of upgrading.Hell, I wasn't even that impressed with the Magnetic Ride in the Denali. It was pretty good.
Not outstanding like I had thought.I did however also drive a 2015 2500HD with an Duramax and Alison. Also a Denali.
And that truck rode phenomenal for being a 2500HD. While I do think the 6.2 8 speed does rob some of the pleasure of 420hp and 460tq it definitely feels way better than every 5.3 I have ever driven. I drove several 14 and 15 5.3 trucks with 3.42 gears and you had to get down on the peddle pretty good to get the truck going.
The 6.2 even with 8 speed moves with very little peddle and effort. My throttle tip in is very good and shifts are quick. I agree with those that say driving under let's say 10 mph in stop and go traffic can be a little frustrating but as soon as there is a clearing the truck moves out with no hesitation.
Now I have not driven or ridden in a tuned 14 or 15 5.3 but could easily imagine it feeling comparable to the 6.2 stock.
Allison Transmission Modelsare the only fully automatic models on the market. Through the years, Allison has updated and upgraded their technology, which they call “Generations”.
This can make it a bit confusing when trying to find parts.Pro Tip: When finding parts for your Allison Transmission, make sure you know what generation your transmission is. Allison Generation 5In 2012 Allison upgraded to the Generation 5 model, which is still in use today.
The 1000/2000 series made the switch first, and then the 3000/4000 series followed. Differences:.
This series focuses on prognostics, constantly monitoring operating parameters and notifying the driver if there’s an issue. This includes oil and filter monitoring, and transmission health monitoring. The shift selectors were also re-designed.Allison Generation 4These transmissions started to appear in trucks in the early 2000s, around 2004/5 time frame.
Difference included:. More sensors, more diagnostic capabilities, and advanced configurations of the Allison Transmission product line.Allison Generation 3In1998, the Allison Generation 3 replaced the original WTEC II transmission controls. Theis generation ushered in the computer-based diagnostic era, which meant you could use a variety of diagnostic tools to connect to the Allison Transmissions to read codes, clear codes, perform diagnostic commands, and more. Other differences:. The controls for the Allison Transmission were updated, offering several different styles.Allison WTECThe oldest Allison Transmission configuration was the WTEC. If your commercial truck, RV, or machine is from before 1998, it probably has a WTEC II transmission. This series had no diagnostic software or computer, but you could retrieve codes from the shift selector.
Popular For a ReasonAllison is the world’s largest manufacturer of fully automatic transmissions and hybrid propulsion systems for commercial-grade vehicles. These transmissions can be found at work in a wide variety of applications, from mining and school buses.to learn more about or to find a part for your series.
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