6.2L 8-Speed Transmission

CounterMeasure · October 6, 2015

2015 1500 , max tow, 6.2. Apr this year. Got the toy hauler travel trailer on it again. Just finished first leg to Myrtle Beach. Northern NJ to Virginia. First. Hill in town, felt like engine was missing. After that ran great, shifted great. Almost like I had a 8speed from cyrsler. Friend has hemi with 8speed. Maybe gm should recruit a cyrsler engineer.

Chrysler is using a ZF 8HP tranny in their trucks. In other words, they left it to German transmission experts for their needs. Ironically, the GM A8/8L90 in our trucks was heavily influenced by the 8HP. GM took it and "tweaked" it, but in my opinion, many of their tweaks took it in the wrong direciton.

sphen22 · October 7, 2015

Hey All,

2015 Denali Blue, love the color.

Anyway I had the reprogram recall done about 3k miles ago. Just passed 11k the other day.

Just took it in to have the oil changed and the 4wd recall done. Also mentioned the same issues many of you are having, clunky shifting at low speed, hesitation when going into drive among the other problems.

Got a call from the dealer today and they told me the Transmission needs to be replaced.

Anyone have any advice on the handling of the situation, what I should try to get the dealership to do for me, like another truck during the downtime excetera.

Also unfortunate as I am moving from California to NH next week and the teuck is scheduled to be trailered east. So I will need to have the service performed in NH.

Thanks

Matt

CounterMeasure · October 7, 2015

Hey All,

2015 Denali Blue, love the color.

Anyway I had the reprogram recall done about 3k miles ago. Just passed 11k the other day.

Just took it in to have the oil changed and the 4wd recall done. Also mentioned the same issues many of you are having, clunky shifting at low speed, hesitation when going into drive among the other problems.

Got a call from the dealer today and they told me the Transmission needs to be replaced.

Anyone have any advice on the handling of the situation, what I should try to get the dealership to do for me, like another truck during the downtime excetera.

Also unfortunate as I am moving from California to NH next week and the teuck is scheduled to be trailered east. So I will need to have the service performed in NH.

Thanks

Matt

When I had my tranny replaced two months after I picked it up off the hauler, it was gone for a little over a week. It took them time to get TAC to be ok with the replacement, then the tranny was shipped via freight from up Detroit, and then took them two days to do the work and all the programming associated with it because they had never done an 8-speed before. Then the shop manager went and put a couple hundred miles on it to make sure it was ok and getting good shift data. In the meantime, I was in a loaner truck for that time, which is standard as far as I can tell with any warranty work early on. Apart from that, I didn't get anything for my inconvience. I did complain to GM about it and all the other issues with my Denali, and all they would do was either 3 or 6 months free SiriusXM.

Good luck!

pm26 · October 8, 2015

When I had my tranny replaced two months after I picked it up off the hauler, it was gone for a little over a week. It took them time to get TAC to be ok with the replacement, then the tranny was shipped via freight from up Detroit, and then took them two days to do the work and all the programming associated with it because they had never done an 8-speed before. Then the shop manager went and put a couple hundred miles on it to make sure it was ok and getting good shift data. In the meantime, I was in a loaner truck for that time, which is standard as far as I can tell with any warranty work early on. Apart from that, I didn't get anything for my inconvience. I did complain to GM about it and all the other issues with my Denali, and all they would do was either 3 or 6 months free SiriusXM.

Good luck!

What did you expect? Just curious: did they install a new or "remanufactured" transmission in your truck?

BlackZ71Silverado · October 8, 2015

After test driving several 6.2L trucks with the 8-speed, I am definitely not in a hurry to buy one of these new trucks. Out of the 6 I was able to drive, not one of them seemed to shift the same. They all seemed like they want to get in the highest gear possible as fast as possible. Only 1 of the 6 seemed to shift to my liking. If I were to buy one, a tune would definitely be the first thing done to try to get the transmission shifting properly.

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Rock1500 · October 8, 2015

Wow, 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.

Well now these days that's all that matter to meet government standards for the fleer considering trucks make up such a large volume of sales.

I have the 2014 and now with 10k miles on it I feel the power is there. Before it wasn't when I first started to use it. I might get a tuner to add more.

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argus · October 9, 2015

After test driving several 6.2L trucks with the 8-speed, I am definitely not in a hurry to buy one of these new trucks. Out of the 6 I was able to drive, not one of them seemed to shift the same. They all seemed like they want to get in the highest gear possible as fast as possible. Only 1 of the 6 seemed to shift to my liking. If I were to buy one, a tune would definitely be the first thing done to try to get the transmission shifting properly.

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Kudos on the thorough test drives to help you make the call. While I really like my power train a good bit as is, I won't lie--I haven't ruled out getting a tune.

BlackZ71Silverado · October 9, 2015

I really prefer my 08 4-speed over my 10 6-speed in factory form. Untuned, my 6-speed is very busy hunting for gears and like the new 8-speeds, get into the tallest gear possible as fast as possible. A tune fixed it and it's been running to my liking since a few weeks of being brand new. My thoughts on these things are that we pay a good amount of money for these trucks and they should perform a little better in factory form. The fuel mileage regulations are definitely to blame because GM has them programmed for the best MPG's possible.

When I do make a putchase I am highly considering a Duramax simply because they don't act like the tassers going through the gears. I really don't need that much truck for what I do but the way the gassers are programmed, I just don't really care for them. If GM gets them disled in better the next few years I'll take another look. If they are still similar, I'll be picking up a Duramax for sure.

Hope you guys like the new 6.2's and get any transmission issues that still remain taken care of. Another thing I hate is the AFM. A V8 should always perform like a V8 IMO, no need to shut half the engine down. I should have picked up a 13 6.2L without the AFM but I couldn't get the ok from my better half. Guess I'll be driving what I have for a few more years, at least.

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redwngr · October 9, 2015

After test driving several 6.2L trucks with the 8-speed, I am definitely not in a hurry to buy one of these new trucks. Out of the 6 I was able to drive, not one of them seemed to shift the same. They all seemed like they want to get in the highest gear possible as fast as possible. Only 1 of the 6 seemed to shift to my liking. If I were to buy one, a tune would definitely be the first thing done to try to get the transmission shifting properly.

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Mine definitely shifts different after getting some miles on it. It changed enough that I'm not sure what can be learned from test driving brand new ones.

I do like the way it shifts when encountering grades towing at freeway speed. Downshifts (and later upshifts) are smooth and quiet, increasing engine speed just enough to get the job done.

I do still occasionally get the 2-1 clunk when coming to a stop.

Joppy818 · November 18, 2015

I would never claim to be an expert. But I have 2k miles on my 15 Denali w/ 6.2l 8 speed, and the first thing I noticed was how smooth the trannny shifts you don't even feel it. I don't even feel it switch into drive. This truck is not my daily and I can also say that once the tranny was cold (truck sat for a month) I may not have let it warm up as long as it should and from first to second did feel very "tall" other then that incredibly smooth and I feel the match is perfectly tuned.. As others have stated it does jump from one gear to the next very fast...I think this was for fuel economy.

I love the manual mode..I don't know if you can get the manual mode in a 6 sp

pm26 · November 19, 2015

Those 6 and 8 speed auto transmissions still have the tow/haul mode, right? You can drive it all the time it that mode, even when running the truck empty and it will not hurt anything. Selecting the tow/haul mode raises the shift points in the transmission and it will just hurt fuel economy somewhat, but will probably shift much better for you.

BobHancock · November 19, 2015

This may be the ticket. I ordered my '16 High Country 6.2 8 Speed 23 Sept. The order was "pulled" 2 weeks ago which means it's in production. No VIN or delivery date yet.

I had a Grand Cherokee with the 8 speed which was flawless. Point is, when I put it into "Sport" mode it did better than I could with the paddles in the twisties. So maybe using the tow/haul mode will let the truck know to get out of EPA mode and into "Truck Guy With a 6.2L Motor" mode. I just hope they've figured this business out for 2016. Not like GM hasn't had the time.

WendysOrBust · November 19, 2015

This may be the ticket. I ordered my '16 High Country 6.2 8 Speed 23 Sept. The order was "pulled" 2 weeks ago which means it's in production. No VIN or delivery date yet.

I had a Grand Cherokee with the 8 speed which was flawless. Point is, when I put it into "Sport" mode it did better than I could with the paddles in the twisties. So maybe using the tow/haul mode will let the truck know to get out of EPA mode and into "Truck Guy With a 6.2L Motor" mode. I just hope they've figured this business out for 2016. Not like GM hasn't had the time.

Really wish GM would do something similar to what Ford is doing on their 2015 lineup by offering 3 drive modes. Normal, Tow-Haul, and Sport.

The feature works by changing the frequency of gearshifts, so the truck stays in the “sweet” spot of the powerband and holds lower gears longer to make driving more fun. That means less shifting on engaging drives, such as twisty roads with rolling hills. Instead of shifting gears up and down for peak efficiency, the transmission holds a specific gear longer to make driving more responsive and spirited.

Sport mode reduces the frequency of having to step on the gas pedal to reach peak torque – resulting in quicker acceleration with less pedal travel. The truck feels more responsive to the driver’s pedal inputs. When combined with the transmission changes, the result is an on-demand performance feel similar to what an aftermarket modification might add to the truck, but with the benefit of maintaining the Ford vehicle warranty.

An advanced feature of F-150’s six-speed automatic transmission is its ability to match engine rpm as it downshifts in slowing for a corner. Electronics calibration for this feature comes straight out of Mustang.

“Sport mode keeps the engine operating in the desired power and torque ranges, or what we like to call the ‘sweet’ spot,” explained Jungbluth. “It makes Mustang come alive, and we feel it does the same thing in F-150.”

Sport mode is similar to F-150’s tow/haul mode, which also changes shift points under acceleration, keeping the truck at a higher rpm and further up in the power range while driving over rolling terrain for an improved towing experience. The technology limits the transmission from shifting up when the vehicle crests a hill, and provides downhill brake support that allows engine-compression braking to slow the vehicle and maintain a steady speed.

Sport mode is standard with every F-150 engine and can be activated in two-wheel drive, four-wheel-drive automatic and four-wheel-drive high settings.

https://media.ford.com/content/fordmedia/fna/us/en/news/2015/08/05/f-150-performance-enhanced-by-new-sport-mode.html

Its a small thing that would go a long way.

BobHancock · November 19, 2015

Yep. That's essentially what Sport in the Grand Cherokee does. I've tried using the gear switches on the shift lever of my 2014 5.3/6 but it's not the same and the shifts hesitate. We may be expecting more from a truck than they are designed for. After all, who tries to drive a pick-up like a sports car? Me.

redwngr · November 19, 2015

Yep. That's essentially what Sport in the Grand Cherokee does. I've tried using the gear switches on the shift lever of my 2014 5.3/6 but it's not the same and the shifts hesitate. We may be expecting more from a truck than they are designed for. After all, who tries to drive a pick-up like a sports car? Me.

Manual mode does not 'force' upshifts.

Manual mode establishes the max gear the trans mission will shift to.

For example, if put in M5 and it will use M1 thru M5 as it deems necessary.