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Posted

I have only owned 14 slt about 3 weeks I drove about 11 hours then off and on for a day or two and never noticed harsh downshift until today. The last time I had it out was to do some reprogramming for recalls. the first thing that came to mind was "what did they do during reprogram". it may just be a coincidence...

Posted

Please keep me posted if you hear of a fix from GM and not a tune. My 2016 exhibits this (6 speed). Been doing it since day 1 with 2 miles on it. I've had the taps reset and a full relearn done and it still remains. The firm downshifts are better when the transmission temp is below 100 but once it creeps above that which it doesn't take long they become much firmer. I also feel a lunge like the torque converter is releasing every once in a while.

 

Dealer say's its normal?!?!?! :bs:

Posted

I have only owned 14 slt about 3 weeks I drove about 11 hours then off and on for a day or two and never noticed harsh downshift until today. The last time I had it out was to do some reprogramming for recalls. the first thing that came to mind was "what did they do during reprogram". it may just be a coincidence...

Did you notice the "hard downshifts" before or after reading this thread? Now that I've read this thread I will be listening carefully when I apply the brakes! I know my transmission is working as it should but discussions like this often heighten my awareness. When I read about shifting concerns with automatic transmissions I often wonder why there isn't greater public pressure on manufacturers to produce more vehicles with manual transmissions. I intentionally did some "hard downshifts" on my motorcycle yesterday wishing I could do the same with my truck!

Posted

Did you notice the "hard downshifts" before or after reading this thread? Now that I've read this thread I will be listening carefully when I apply the brakes! I know my transmission is working as it should but discussions like this often heighten my awareness. When I read about shifting concerns with automatic transmissions I often wonder why there isn't greater public pressure on manufacturers to produce more vehicles with manual transmissions. I intentionally did some "hard downshifts" on my motorcycle yesterday wishing I could do the same with my truck!

I noticed before the post. I drove the truck 1000k interstate so that doesnt count then i drove the truck maybe 4 times and a total of about 200 miles. and did not notice the hard shift until after i had the recalls done. maybe i just didn't notice them , maybe that was the first time it happened its just hard to say with out having more time behind the wheel.

Posted

well I went back to the dealer on Thursday when it was acting up again. They plugged it in and didn't find anything weird because there was no check engine light on and mechanics nowadays have no idea what to do if there isn't a light on. They began to feed me the BS that its normal. Funny thing is the guy in the service department didn't know that my truck has been there for trans work twice in the past 2 weeks (once for a converter, and 5 days later for valve body). So after he began to tell me its normal I dropped the bomb on him that 2 of his mechanics drove the truck on different occasions and agreed that my downshifts were not "normal" and they took it in for warranty work. I also told him the 2016 Silverado's they gave me for rentals didn't shift like that. So he shut up real quick about it being normal. I got the whole conversation recorded on my phone in my pocket. He ultimately told me to bring the truck back Monday because that's when the transmission guy would be in. So I dropped it off yesterday. If it isn't fixed this time I am getting a lawyer and going with the lemon law. This is the 3rd time for the same problem. I'm so done with these shitty transmissions.

 

I'll wait to see if they fix my truck before I post up the name of the dealer and my phone conversation. Its time for them to step up and replace my transmission.

Posted

well I went back to the dealer on Thursday when it was acting up again. They plugged it in and didn't find anything weird because there was no check engine light on and mechanics nowadays have no idea what to do if there isn't a light on. They began to feed me the BS that its normal. Funny thing is the guy in the service department didn't know that my truck has been there for trans work twice in the past 2 weeks (once for a converter, and 5 days later for valve body). So after he began to tell me its normal I dropped the bomb on him that 2 of his mechanics drove the truck on different occasions and agreed that my downshifts were not "normal" and they took it in for warranty work. I also told him the 2016 Silverado's they gave me for rentals didn't shift like that. So he shut up real quick about it being normal. I got the whole conversation recorded on my phone in my pocket. He ultimately told me to bring the truck back Monday because that's when the transmission guy would be in. So I dropped it off yesterday. If it isn't fixed this time I am getting a lawyer and going with the lemon law. This is the 3rd time for the same problem. I'm so done with these shitty transmissions.

 

I'll wait to see if they fix my truck before I post up the name of the dealer and my phone conversation. Its time for them to step up and replace my transmission.

 

Do keep us posted with what they do to try and fix it.

Posted

just an update from me.

I drove the truck all day around town today and only had 1 instance of a harder down shift while turning into a parking lot. i am going out on a limb here but it seems i had the problem after dealer reprogrammed but after driving it all day it seemed to re learn or resolve the issue on its own.

 

if I notice it happening again I will update but it was definitely hitting hard the day i got it back from dealer and not today so.... i'm not sure

Posted

just an update from me.

I drove the truck all day around town today and only had 1 instance of a harder down shift while turning into a parking lot. i am going out on a limb here but it seems i had the problem after dealer reprogrammed but after driving it all day it seemed to re learn or resolve the issue on its own.

 

if I notice it happening again I will update but it was definitely hitting hard the day i got it back from dealer and not today so.... i'm not sure

mine will do the same. some days its smooth other days it slams gears

Posted

Mine always exhibits a firm bump when downshifting. I don't hear any clunk or anything like that but its a very firm bump when going from 4-3, 3-2 and 2-1. Typically starting at 30mph and below that.

 

Maybe mine is normal then? I test drove a 2017 Sierra which did almost the same exact thing. I dunno. If this is the norm its definitely not easy to get used to as I'm always focused on it.

Posted

well I just got the call. GM corporate will not allow a new transmission to be installed in the truck. When I asked if the truck was fixed I was told yes the transmission has nothing wrong internally. Which means no they didn't do anything. This sucks. Whats the point of a warranty if GM wont allow the parts the truck needs? I took 2 of their mechanics for rides in the truck on 2 different occasions and both times the mechanics agreed something in the trans was not right and the truck needed service.

 

I guess I have to start all the lemon law paperwork and bullshit. Fun Fun. **** these new silverado transmissions

Posted

well I just got the call. GM corporate will not allow a new transmission to be installed in the truck. When I asked if the truck was fixed I was told yes the transmission has nothing wrong internally. Which means no they didn't do anything. This sucks. Whats the point of a warranty if GM wont allow the parts the truck needs? I took 2 of their mechanics for rides in the truck on 2 different occasions and both times the mechanics agreed something in the trans was not right and the truck needed service.

 

I guess I have to start all the lemon law paperwork and bullshit. Fun Fun. **** these new silverado transmissions

Lemon law, Buyback, or more than likely if the dealer is a reputable dealership they will offer a trade allowance. First two get you out of the truck, 3rd gives you most trade value with help from GM, but you are "forced" into another GM truck. Good luck on which path you choose.
Posted (edited)

im going to try for the lemon law as hard as I can. im sick of having to leave work early to take this shitbox to the dealer who cant fix it. im going to try to legally fcuk them as much as possible

Edited by njk4o5
  • 1 year later...
Posted

My 2015 does this as well, I’ve taken it to the dealer and was told it was because of my k&n oiled filter got oil on my mass airflow sensor. They said put stock airbox back on and they would clean the sensor and do a trans relearn


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk

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