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Surging '17 Z71 5.3??


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Posted

Howdy all, I have come back to GM and just bought a '17 Z71 5.3. It has about 350 miles it and has a pretty obvious pulse/surge/skip thing going on under slight acceleration, my wife even noticed....

While this happens the V8 light stays lit, and it doesn't appear to be shifting , once you crowd it a bit it will downshift and clear up.

 

I called the dealer and got a very scripted "totally normal" so I asked what it was and he said "it's the ahhh V4-V8 coming and going and the transmission shifting to accommodate"

 

I don't by it. What do you guys think??

 

 

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Posted

 

FYI

 

I've had a similar shifting issue with my 2017 (5.3L, 6-speed) since buying it new in December. It seemed to occur most frequently when applying light throttle on an incline, when switching from V4 mode to V8 mode. I live in a hilly area so this was a big annoyance. My solution was to use a Range module to turn off AFM and keep it in V8 mode all the time. This was somewhat effective, but I would occasionally still get the surging under light throttle.

 

However, I had the TSB mentioned above done last week and it solved 95% of the issue, to the point that I can run it without the Range device plugged in. Occasionally I get a slight hesitation, but nothing like before.

Posted

I called a local repair shop (with an impeccable reputation) and asked if I gave them my vin and the above TSB could they print something out for me, they were more than happy to and I plan on stopping in tomorrow to take a look. Friday I'm gonna be down near where I bought it to have my winders tinted and will stop in and ask the service about an update. On another note-I looked into the gas pedal (formally know as) and all seems good as far as free play.

 

 

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Posted

might want to put a few more miles on it first. My truck had sluggish acceleration , funny shifting until about 500 miles. Truck runs like a champ now

  • 2 weeks later...
Posted

Howdy all, I have come back to GM and just bought a '17 Z71 5.3. It has about 350 miles it and has a pretty obvious pulse/surge/skip thing going on under slight acceleration, my wife even noticed....

While this happens the V8 light stays lit, and it doesn't appear to be shifting , once you crowd it a bit it will downshift and clear up.

 

I called the dealer and got a very scripted "totally normal" so I asked what it was and he said "it's the ahhh V4-V8 coming and going and the transmission shifting to accommodate"

 

I don't by it. What do you guys think??

 

 

Sent from my iPhone using Tapatalk

Same trouble with my '17 GMC with about 1500 miles on it. Saw other owners with the same complaints and I'm happy to know it's not just me. Originally I thought it was the v4/v8 going on/off but it's definitely not. I've seen the service bulletin and I'll have it checked whenever I get around to the first oil change. I've been lagging on taking it in because I figured I'd have to find a way to make it happen consistently when the GM tech went along for the ride.

Posted

Same trouble with my '17 GMC with about 1500 miles on it. Saw other owners with the same complaints and I'm happy to know it's not just me. Originally I thought it was the v4/v8 going on/off but it's definitely not. I've seen the service bulletin and I'll have it checked whenever I get around to the first oil change. I've been lagging on taking it in because I figured I'd have to find a way to make it happen consistently when the GM tech went along for the ride.

My '17 Silverado has it as well, 2k miles in. Feels like it's been getting better lately, but that could just be me learning to accelerate at the rates where it's not as noticeable. Going to do the same thing and have it checked at the first oil change, just hope they don't give me any nonsense cause of my intake/exhaust. Keep us posted with how it goes at the deal, I'll do the same.

 

Bob

Posted

i just purchased a 2017 all terrain and i have this same problem i only put 405 miles on it and i noticed it when i drove off the lot now its driving me nuts gona have to contact them to try and resolve problem this sucks brand new truck and it has to be serviced allready

Posted

i just purchased a 2017 all terrain and i have this same problem i only put 405 miles on it and i noticed it when i drove off the lot now its driving me nuts gona have to contact them to try and resolve problem this sucks brand new truck and it has to be serviced allready

My wifes' car is a new 2016 Honda Accord and within a few months it had issues starting without the starter turning for 5-10 seconds. Honda couldn't re-create the problem so I took video with my phone to prove it. Even a brand new Honda can have problems and it just comes with the territory I suppose. Like SilveradoH said I think I'm just driving around the problem by pressing the pedal in ways that I know won't make it feel like it's misfiring/surging/jumping. Even my passengers have noticed so it's definitely a problem that I need to get resolved. Good luck with yours as well.

Posted

I'm not sure if mine has gotten better (can't imagine it healing itself) or Im getting used to it. I do find it unacceptable that a $46,000 auto has an issue like this. I'm gonna give it more time before going back to the dealer, maybe by then they will have seen more of them and won't be so dismissive.

 

 

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Posted

But then again, if that's all that I have to complain about I'm ok with that.

I came back to GM after having a '12 F150, loved the truck. It was the most reliable truck I've ever had-not one single trip back to the dealer..period. Before that I ordered a new '04 Z71 I replaced the heads, wheel bearing assemblies, rear calipers, u joints, wiper control module, radio, diff cover, heater control,the cab corners rusted out and the rockers were rusted. It was just 9yrs old and had ONLY 86,000 on her. I said I'd never own another GM....but this one is the quietest, smoothest, most comfortable one I've had!

 

 

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  • 2 weeks later...
Posted

Took my truck into the dealer yesterday and the service rep told me I needed to prove the problem to the tech before they could fix it. I took the tech for a drive and couldn't make the problem happen even though it happens almost daily. He was a good tech and I know he probably deals with these type of problems on a daily basis. Just like going to the doctor and you start to magically feel better right before you head into the office! I showed him the service bulletin and he said he'd look into it. Thankfully they applied the update and hopefully the problem has been fixed. I've driven it for only a day so far but I usually would have felt the misfire/chuggle/whatever by now. I'll post again if the problem comes back.

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