8spd issues

David DeSouza · December 27, 2020

Thinking about buying a 2021 Texas edition with a 5.3 and the z71 package, I would like to get a 10spd but trying to keep the purchase price below 40k! Has all the issues been resolved with the 8spd or is better to get a higher trim that has the 5.3/10spd combo?

SilveradoRST · December 27, 2020

Had my 8 speed for 15 months now. No issue other than a hard 1-2 on cold mornings. But once it gets up to operating temp it is smooth as can be.

Silverado4x4 · December 27, 2020

My 19 Z71 8 speed had the stutter while giving it a light throttle in-between shifts but once they flushed the tranny and put the new updated trans fluid in it has been smooth as butter.

My 19 was a November of 2018 build which had the fluid from the factory that was absorbing moisture causing the stutter in-between shift under light throttle then they issued a TSB for the issue to put a new type of fluid in and its been great but since you are getting a 21 the issue wont be there as it will have the new fluid in it.

SilveradoRST · December 27, 2020

20 minutes ago, Silverado4x4 said:

My 19 Z71 8 speed had the stutter while giving it a light throttle in-between shifts but once they flushed the tranny and put the new updated trans fluid in it has been smooth as butter.

My 19 was a November of 2018 build which had the fluid from the factory that was absorbing moisture causing the stutter in-between shift under light throttle then they issued a TSB for the issue to put a new type of fluid in and its been great but since you are getting a 21 the issue wont be there as it will have the new fluid in it.

When did you buy the truck? I read elsewhere that the dealer is suppose to change to the new ATF for all the trucks on their lot after March 2019 before sale?

2024Denali · December 27, 2020

31 minutes ago, Silverado4x4 said:

My 19 Z71 8 speed had the stutter while giving it a light throttle in-between shifts but once they flushed the tranny and put the new updated trans fluid in it has been smooth as butter.

My 19 was a November of 2018 build which had the fluid from the factory that was absorbing moisture causing the stutter in-between shift under light throttle then they issued a TSB for the issue to put a new type of fluid in and its been great but since you are getting a 21 the issue wont be there as it will have the new fluid in it.

Same! Harsh shift every once in a while first thing in the morning. Other than that, works great! Barely notice it shifts.

Silverado4x4 · December 27, 2020

25 minutes ago, SilveradoRST said:

When did you buy the truck? I read elsewhere that the dealer is suppose to change to the new ATF for all the trucks on their lot after March 2019 before sale?

Mine was bought 1st week of March of 2019 but didn't have the issue until I put about 7000 miles on it.

Edited December 27, 2020 by Silverado4x4

Moend · December 27, 2020

3 hours ago, SilveradoRST said:

Had my 8 speed for 15 months now. No issue other than a hard 1-2 on cold mornings. But once it gets up to operating temp it is smooth as can be.

+1

asalinasz39 · December 27, 2020

My 19 8spd/5.3 has been overall very smooth. It has done the hard shift coming out of my driveway very rarely in the 18 months I have owned it. I have 19k miles on it and It sure has been much smoother than my 17 8spd/5.3

Although I do wish I could have the 10speed because if you plan to upgrade tires the 3.23 gears will go better with those extra speeds.

Sent from my iPhone using Tapatalk

BigMick2023 · December 27, 2020

2020 RST with 5.3 8-speed....

Zero issues with the transmission or otherwise......this truck has been flawless so far and never been back to the dealer.

Owned it for just shy of 1-year now.

lebag335 · December 27, 2020

My ‘19 TB LT 8 speed bucked pretty good. My ‘20 AT4 8 speed is smooth as butter! Huge difference.

dgstarr63 · December 27, 2020

My 2021 Silverado Crew cab, 4wd, 5.3, 8 speed, 3.23 axle has been flawless in every way, including the transmission. Gas mileage has increased 1.5 to 2 mpg better than my 2015, 5.3, 6 speed, 3.42 axle.

UGADawgs · December 28, 2020

My 2019 5.3/8-speed has been acting up lately. It seems like it is hunting gears when it shouldn't be shifting. Going to take it in this week and see if they'll change the ATF under the TSB.

https://static.nhtsa.gov/odi/tsbs/2020/MC-10174268-9999.pdf

SilveradoRST · December 28, 2020

47 minutes ago, UGADawgs said:

My 2019 5.3/8-speed has been acting up lately. It seems like it is hunting gears when it shouldn't be shifting. Going to take it in this week and see if they'll change the ATF under the TSB.

https://static.nhtsa.gov/odi/tsbs/2020/MC-10174268-9999.pdf

If you don't mind, what's the build date and when did you buy it off the lot?