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Posted (edited)

I Purchased my 2015 silverado z71 crew cab a couple months ago, so far i love the truck accept for one issue that shows itself every once in a while. USUALLY while turning and acceleration lightly at the same time ( lugging the motor pretty much) ill get a very noticable shudder right before the truck FINALLY decides to downshift. Has anyone had a similar issue. Im going to drives my buddies sierra tomorrow and see if i get the same shudder. I have 3600 miles on this truck so i dont think its anything to do with the "adaptive" transmission learning cycle. Ive heard a custom tune can resolve issues but i really hate to do that on this new of a truck, nor do i have anywhere within 400 miles to get it done. New to the forum guys, hope to get some responses, this is my first GM product. Switched from a 2008 tundra with 245000 trouble free miles. Hope i dont regret this purchase :chevy:

Edited by Tommyz71
Posted

Have you looked to see if the truck is still in V4 mode when you get the shudder? My 2014 would lug, shudder, downshift/clunk, and then kick back into V8 mode. It was absolutely horrible prior to the 15604 transfer case recall / driveability update.

Posted

Have you looked to see if the truck is still in V4 mode when you get the shudder? My 2014 would lug, shudder, downshift/clunk, and then kick back into V8 mode. It was absolutely horrible prior to the 15604 transfer case recall / driveability update

 

I think it is still in v4 when this happens. But either way it doesnt seem like a brand new truck should do this. Maybe im wrong. I havent talked to the dealer about it yet because it seems they havent been much help on these new model trucks for anyone else.

Posted

 

I think it is still in v4 when this happens. But either way it doesnt seem like a brand new truck should do this. Maybe im wrong. I havent talked to the dealer about it yet because it seems they havent been much help on these new model trucks for anyone else.

 

You're right. They shouldn't, but they do. I wouldn't waste your time at the dealer as they'll likely tell you it's normal. You can turn off AFM with a Range device, or with a tuner. Trust me, it's much better without it, and mileage likely won't suffer. Mine actually improved 1mpg with it turned off. Based on others' experience, at worst you'll lose 1 mpg.

 

Good luck...

Posted (edited)

There is a service update for torque converter clutch shudder on the 8 speed. (Jul 2015 timeframe IIRC)

 

I think it is programming changes only.

Edited by redwngr
  • 2 weeks later...
Posted

I Purchased my 2015 silverado z71 crew cab a couple months ago, so far i love the truck accept for one issue that shows itself every once in a while. USUALLY while turning and acceleration lightly at the same time ( lugging the motor pretty much) ill get a very noticable shudder right before the truck FINALLY decides to downshift. Has anyone had a similar issue. Im going to drives my buddies sierra tomorrow and see if i get the same shudder. I have 3600 miles on this truck so i dont think its anything to do with the "adaptive" transmission learning cycle. Ive heard a custom tune can resolve issues but i really hate to do that on this new of a truck, nor do i have anywhere within 400 miles to get it done. New to the forum guys, hope to get some responses, this is my first GM product. Switched from a 2008 tundra with 245000 trouble free miles. Hope i dont regret this purchase :chevy:

http://www.gm-trucks.com/forums/topic/178059-2015-silverado-53-slip-yoke-clunk/

 

Check out my post, I have the same 2015 truck 6 speed with the same shudder and more, it clunks pretty loud, and it hunts for gears randomly. I got approx 3,6xx miles. I have taken it to the dealer 3 times (documented) for this already, they will tell you its normal and that there is nothing to fix. but my previous gen silverado never did this and it had almost 200k miles by the time i sold it.

 

I already filed with BBB AUTOLINE and manufacturer is dicking me around, GM asked bbb to deny my claim.

 

I am debating on wether to go through with arbitration or if i should just sign a retainer for an attorney.

  • Like 1
Posted (edited)

You're right. They shouldn't, but they do. I wouldn't waste your time at the dealer as they'll likely tell you it's normal. You can turn off AFM with a Range device, or with a tuner. Trust me, it's much better without it, and mileage likely won't suffer. Mine actually improved 1mpg with it turned off. Based on others' experience, at worst you'll lose 1 mpg.

 

Good luck...

I'm about ready to do this. I've only heard good things about those getting a custom tune.

I'm calling my dealer tomorrow to make a big deal about this. There's no reason for the newest and most expensive vehicle I've had to shift worse than a $2000 Pontiac Grand Prix that's 16 years old.

Edited by Haus_Z71
  • Like 1
Posted (edited)

I am curious to know if anyone has had this problem fixed. Mine does the exact same thing, and I have had no success with the dealer. GM was non-responsive via my arbitration request with NMVB (California), and before I retain someone I am just hoping to resolve. Shame they let something so simple like this fester until you have to think about getting a lawyer.

Edited by jtoolze
Posted

I Purchased my 2015 silverado z71 crew cab a couple months ago, so far i love the truck accept for one issue that shows itself every once in a while. USUALLY while turning and acceleration lightly at the same time ( lugging the motor pretty much) ill get a very noticable shudder right before the truck FINALLY decides to downshift. Has anyone had a similar issue. Im going to drives my buddies sierra tomorrow and see if i get the same shudder. I have 3600 miles on this truck so i dont think its anything to do with the "adaptive" transmission learning cycle. Ive heard a custom tune can resolve issues but i really hate to do that on this new of a truck, nor do i have anywhere within 400 miles to get it done. New to the forum guys, hope to get some responses, this is my first GM product. Switched from a 2008 tundra with 245000 trouble free miles. Hope i dont regret this purchase :chevy:

 

Try driving your truck in M5. This will lock out V4/AFM.

Posted

My 2015 8sp is shuttering bad. It started around 7k and I have 11k on it now. Gets worse every time I drive it. Took it to the dealer three times. Once for TCM Update, twice since the shuttering. It will do it at any speed, any gear under constant throttle or light acceleration. GM of course has give me the runaround. The first tech said it needed a torque converter but they were waiting on an improved version to come out in about a month. Right when the month was about up the service manager called me and said there wasn't a fix and he didn't know why the tech put it on the receipt. I told the service manager to schedule me an appointment for the following Friday so I could show him what my truck is doing. He wasn't there when I took it in. The tech that checked it again said it needed a torque converter. He ordered it and may come with a new trans. Part was supposed to be here around 7 days from 11-20-15. Still waiting.

My major concern is, if this thing has been shuttering this long there is probably some wear on something. My hopes is that they do the whole trans.

When it shutters, it's so bad the steering wheel is bouncing up and down. Feels like I got some 12s in the back.

 

 

Sent from my iPhone using Tapatalk

  • 3 weeks later...
Posted

Yeah my 2015 is doing the same thing as described here by all of you. I had the dealership service manager at ride with me, he of course agreed with me that it was happening consistently. They have a TSB on it, he did the work, involved lifting cab, unhooking exhaust, setting cab back down on pads, that is all bull though, because it happens whether or not you can feel it. Its always happening in V4 under light acceleration, then it stops once in V6 mode.

 

Dealership wants to compare it to another truck with same configuration which is not popular here in Seattle area. 5.3L is more common here.

 

I suppose that I don't need the AFM but dangit, that's what I paid for. I may have to hire an attorney- I'm not sure. If I do, I am done with Chevy.

 

P.S. They opened a case on it (some guy in Manila- way to go Chevy. More jobs overseas.

  • 2 months later...
Posted

Update, last friday my attorney informed me that GM will buy back my truck. Easy fix.

 

How does this work? What if you had a trade which put you a tad upside down, how would this work then?

  • 4 weeks later...
Posted

 

How does this work? What if you had a trade which put you a tad upside down, how would this work then?

not sure depends what offer the manufacturer gives you , and what your attorney can negotiate

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