Who likes their 8 Speed?

FADEC · May 15, 2016

Lots of good information in this thread, thank you for the help. I feel as if I got a lemon and think I will still stick with the 6.2L and the 8 speed. The power of the 6.2L is intoxicating; especially compared to my last truck which was a 2009 Avalanche.

I traded in a 2009 Avalanche as well. The 6l80 was a nice tranny. Always very smooth!!

JacobC1983 · May 15, 2016

I loved that truck..... it was kind of gutless and I always wished I had bought one with the 6.0L when I could have.. but I really loved that truck. Everything about it.

And it always rode smooth and soft on the highway on long trips.

Edited May 15, 2016 by JacobC1983

Missing_link · May 15, 2016

Driving in stop and go traffic mine doesn't shift the way I would expect.

Just got back from towing my 9000 pound trailer and it shifts awesome when loaded

Linc

JacobC1983 · May 15, 2016

Did you use tow/haul mode?

SierraMyst · May 15, 2016

This my truck too.... It can be a real nightmare.

Don't get me wrong, I love the truck.

It is by far the worst driving truck I've ever driven.

But by far the best looking, feature filled, luxurious, comfortable truck I've ever owned.

How can you make such a great truck and drop the ball on the tranny of all things.

JacobC1983 · May 15, 2016

Exactly.... If it wasn't for the transmission it would be one of my favorite vehicles.

flasch192 · May 15, 2016

53,000 dollar truck you shouldn't have too spend a dime too make it perform like it should!

That being said mines a 5.3 with 8 speed and is in the shop for the second time finally threw a trans code the other day maybe the dealer will get off their ass and do something, 3 strikes gm and your out, ur on #2 if I get it back this time and it's not fixed back too ford I go !

kp52 · May 15, 2016

I traded in a 2009 Avalanche as well. The 6l80 was a nice tranny. Always very smooth!!

Dont fret, they screwed up the 6 speed in the 14+ trucks as well lol. I had a '15 5.3 6 speed, just bought a new '16 5.3 6speed and they both shift the same - like crap. Lazy/harsh downshifts, all kinds of low speed clunks and banging shifting. Luckily turning off grade braking makes it behave like a normal trans, shame it doesnt help the 8 speeds.

Snoringbear · May 15, 2016

I love mine, 2016 Sierra SLT with 5.3. First 3k miles were a little rough at times but at just under 5k it's now smoothed out.

Very rarely when the truck first starts up and you put it in gear it does a funny thing where it feels like the torque converter won't lock up. When pulling out of the garage (in drive, not on the gas at all) the truck barely wants to move, usually it will roll right out just idling. If I touch the gas at all it takes off kind of like you're "dumping the clutch" for lack of better ways to describe it. The problem goes away within a few seconds and doesn't happen often enough for me to really be concerned about it.

Have the 6.2 and I like mine as well, especially when towing, does a good job of keeping engine in sweet spot. However, I kinda had to learn how to drive it. 1st gear is really low, what we referred to back in the day as Granny or compound gear. Anyway, if taking off from a dead stop a bit slow or light footed it wants to shift almost immediately into 2nd which causes what I would call a hiccup or jerking feel. So, I've learned to take off more aggressively which tends to smooth out the transition from 1st to 2nd.

Missing_link · May 15, 2016

Did you use tow/haul mode?

Yes and it holds gears great on hills!! The 6.2 has an amazing amount of power pulling that much weight. Cruise set on 70 and 3200 rpm was as high as it got climbing hills. Spent most of the time in the 2200 - 2700 rpm range

Linc

seamus2154 · May 16, 2016

I see most of you that have replied have a 2015, which is the same year I have. I was curious of there was a correlation between people who liked their 8 speed and people who didn't and if they had a 2015 or 2016 model. I read there was a possibility of an updated 8 speed transmission with a new torque converter and valves in the 2016 model.

Maybe I am just one of the unlucky ones.

I too have 2015 denalli and my 8 speed is pretty good. I was furious w/ my '15 Sierra w/ the 6 speed which was horrible w/ never being in right gear, lugging, and clunking. Hated it. So traded on the denalli w/ 6.2 and 8 speed and love the upgrade.

I did recently get a shudder towing and really believe it was the trailer. But when I went in to ask about it, the service manager who I know said we have a torque converter defect in many of the 8 speeds. A manufacturing issue when it was pressed together ruining an interior seal. They said bring it in we will just do the torque converter that fixes every one of them. They did which included the new torque converter, filter, two flushes of new fluid, and new software upload from GM. I think he said it addresses the new torque converter but also something about when it's in 4 cylinder mode? Its perfect now, and loving it.

Edited May 16, 2016 by seamus2154

camcamaro1991 · May 16, 2016

Disable you powertrain grade braking (unless you're towing), sucks you have to do it every time you cycle the key.

IMO it drives much better.

mookdoc6 · May 16, 2016

Not sure what to say......5.3 Sierra 8speed 2wd CC SLT 2016

It was pretty dang smooth out of the dealer lot. I could feel 1-2-3 the rest not really at all. Drove it like normal rolling stops, parking lots turning corners etc. the dreaded rush hour crap. Yes, it would have it's moments had me thinking is this really how it's going down I pay 40+ grand for this? Anyway, it lessons over the next few days go to dealer to give survey and find out where my splash guards and tint are they promised. The sales manager saw me and asked how you liking it? I said, "I do but the steering wheel is cocked and not centered and once in a while my 1-2-3 gears is rather harsh? He told me the steering wheel is made that way on purpose for a number of reasons and the Tranny will take a few thousand miles don't worry it's normal.

So now here I am at 1500 miles and man is it treating me NICELY! Just ripped up a large grade/mountain and the shifting was nonexistent! Very impressed it shifts on point in the perfect power band while grabbing next gear without any fluctuation and just keeps blasting up the hill! So either I am the only one who got lucky out of tens of thousands of units selling a month or they are all driving Fords and think the 2.7 ecoboost is the greatest thing since sliced bread. Really, 5,500 pound truck up a mountain with a small camper, loaded gear, wife and kids and under the hood is a V6 a 2.7 liter absurdly small blown V6? Only a Ford guy would except that as gospel........I am averaging 21.6 V8 with 8speed loving it buddy!

SkiDooNick700 · May 16, 2016

I do like my 8 speed. Every time I leave work, I turn out of the parking lot onto a road with a 40mph speed limit. Every shift, especially the 2-3 shift, jerks the truck a little. Once it cycles through those gears once, its pretty smooth the rest of the way home. I just don't think it shifts quite right until it gets some temp in the fluids.

I just don't understand why GM can't get these trans more-better lol. I've driven a few different GM vehicles and the trucks (1500 series, at least) are the only ones, in my experience, which have the clunky jerky upshifts/downshifts.

One time I had to jam the brakes to a stop and it made a loud bang and actually pushed the truck forward despite the hard braking I was doing.

I do enjoy my 8speed overall. Especially when towing or romping on it

Edited May 16, 2016 by SkiDooNick700

mitchellb2005 · May 16, 2016

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 when to step on it and not to, it rarely does anything weird.

It's awesome to heavily step on the throttle without actually hammering it, and let the the 6.2 run through all of the gears to about 80mph. Feels like I'm driving a "muscle truck" with a buttery smooth transmission.

Edited May 16, 2016 by mitchellb2005