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Who likes their 8 Speed?

JacobC1983
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AZbound New Member

AZbound

Posted
Posted

Thank you for this. My 16 just started doing this. Early mornings and after sitting in the parking got for a few hours.

 

I'll shift reverse, back out of my spot, and shift into drive and it'll take a couple seconds to engage drive.

 

As always, it doesn't do it all the time and so the dealer will tell me it can't be replicated.

 

Do you have any of the other pages to the TSD?

 

Mine does the same thing. 2015 with 35K and several trips to the dealer and absolutely no results. Often when it does engage a very audible clunk can be heard.

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JacobC1983
JacobC1983

I care about warranty.... It pays for repairs that otherwise I would have to pay for out of pocket. Actually, lots of people care about warranty on a $50k+ vehicle.

mitchellb2005
mitchellb2005

I love my 8 speed. I never hate it, but sometimes it does small annoying things, but I expected an 8 speed to be a little finicky sometimes since I also have an 8 speed in my Audi A7. Once you learn w

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Glava2876 Enthusiast

Glava2876

Posted
Posted

As the title states.... My 2015 GMC Sierra with the 6.2L and 8 Speed is at the dealership again with a field service engineer hoping to fix the transmission for the 5th try.

 

I will trade it in on another GMC Sierra.. and I want the 6.2L again. As you know, this sticks you with the 8 Speed transmission.

 

So.... Who has a trouble free 8 speed transmission? I have read many threads of problems, but hope to find those without problems to make the final decision: Do I get the 8 speed again in the 2016 model or do I downgrade to the 5.3L and the 6 Speed.

 

 

Please put in miles and year of your vehicle with any explanation you want in the thread.

 

I have 9,600 miles on my 2015 Denali CC 6.2 and I love the 8 speed.

To be fair, I had to bring it in at about 1,500 miles because of a hard 2-1 downshift when coming to a stop.

The dealer did some updates and it has been great since that time.

When you step into it, I love the shift point increase and the nice crisp shifts.

scott.moody.9401 Enthusiast

scott.moody.9401

Posted
Posted

Love mine, 2016 5.3 w/ 8-spd, 7300 miles. The only issue I have is, most of the time, the first shift in the morning is late and firm. It not objectionable but its different and noticeable. It can be minimized with just the right amount of throttle. After that, it's fine

 

Sent from my SM-T817V using Tapatalk

JacobC1983 Enthusiast

JacobC1983

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So nobody has hard downshifts that emanate through the entire drivetrain? Mine happen about once a week or once a tank of gas... There must have been something wrong with mine from the factory.

JacobC1983 Enthusiast

JacobC1983

Posted
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Posted (edited)

What problems did it do before the tune, what did the tune fix, and what problems does it still have?

Edited by JacobC1983
thetruck454 Enthusiast

thetruck454

Posted
Posted

Some is a preference, for instance during aggressive throttle it used to shift so smooth you didnt feel it, now it hits on each shift. Normal driving is still smooth. On some of the shifts it would have an odd delay like it was slipping, now each shift is purposeful. It does downshift with less throttle now. Things that still anoy me are when it goes through the gears on steady throttle it doesn't shift at the same rpm, like 1-2 @ 4500, 2-3@ 4400, then 3-4. @ 3800, etc. It feels like it shortshifts sometimes. Also it still clunks on decel, which anoys me.

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JacobC1983 Enthusiast

JacobC1983

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Ah dang.... the clunk on decel was one of the things I hoped a tune might fix.

thetruck454 Enthusiast

thetruck454

Posted
Posted

Ah dang.... the clunk on decel was one of the things I hoped a tune might fix.

It still might, but I dunno. I'm still on the first iteration tune with Justin. It will be several back and fourths so it may be better. Right now he's working on tuning the blower, I'll focusbon the transmission after the engine is set.

tallspawn Enthusiast

tallspawn

Posted
Posted

I drove all the way home with grade braking off today, wow what a difference on the down shifts. Mines is never horrible but that cleaned up some little weirdness. Dang thing will coast forever now lol.

 

Sent From My Galaxy S6 Edge+

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JacobC1983 Enthusiast

JacobC1983

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I have 9,600 miles on my 2015 Denali CC 6.2 and I love the 8 speed.

To be fair, I had to bring it in at about 1,500 miles because of a hard 2-1 downshift when coming to a stop.

The dealer did some updates and it has been great since that time.

When you step into it, I love the shift point increase and the nice crisp shifts.

This was one thing I always liked about my truck too. When my foot was in it, the thing was a delight... Nice smooth and quick shifts ... It's when my foot wasn't in it that caused the problems.

Dunc Enthusiast

Dunc

Posted
Posted (edited)

Love it with grade braking off and think it's "decent, but really confused" with it on. Very smooth shifting.

Edited by Dunc
wetcoaster Enthusiast

wetcoaster

Posted
Posted

Mine's in the shop since yesterday afternoon for rough shifting and the 'Chevy Shake' at 70mph. Not sure what's happening but I have a loaner 2016 Silverado LT 5.3 with the 6 speed and it seems to shift great!

JacobC1983 Enthusiast

JacobC1983

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Mine's in the shop since yesterday afternoon for rough shifting and the 'Chevy Shake' at 70mph. Not sure what's happening but I have a loaner 2016 Silverado LT 5.3 with the 6 speed and it seems to shift great!

 

 

I just drove my loaner 2016 GMC Sierra SLT with the 5.3 and 6 speed for about 1000 miles and I think it shifts very good. With grade braking off it is perfect, but with it on is is substantially better than my 8 speed ever was.

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