Transmission problems
12-06-2018, 07:09 PM
#1
2nd Gear
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Transmission problems
Recently upgraded my automatic transmission in my C7. Mechanic changed the “transmission computer”. Transmission worked great for the first week, but now having issues. Extremely hard to explain, but when coming to a stop, once transmission shifts down to second or third gear, the car will stop itself almost immediately. I then have to put it in park and then back to drive. Obviously this is an issue, but an extreme issue when there is a car behind me.
Update.... the car will no longer drive forward. Once shifted into drive, the car acts like it is stalling out and will not go forward. Luckily this started while I was just down the street from my home and was able to reverse back home. Thoughts?
Update.... the car will no longer drive forward. Once shifted into drive, the car acts like it is stalling out and will not go forward. Luckily this started while I was just down the street from my home and was able to reverse back home. Thoughts?
12-06-2018, 07:10 PM
#2
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12-09-2018, 02:50 PM
#4
Race Director
Obviously you have some real problems. A torque converter that is not unlocking is one of them. Is your mechanic a gm dealer guy or independent?
12-10-2018, 12:19 PM
#6
2nd Gear
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Thanks for the responses. My guy is an independent guy. The pump had to be replaced and has a new one in now. Maybe a bad pump?
The car is now back in the shop and he will attempt to figure it out. May end up having to take it to a dealership, but the issue with that is the car has been upgraded in so many ways, to include the transmission.
The car is now back in the shop and he will attempt to figure it out. May end up having to take it to a dealership, but the issue with that is the car has been upgraded in so many ways, to include the transmission.
01-22-2019, 10:43 PM
#8
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the A8 issues are not specific to a certain model of car, it is a pandemic, all A8s are subject to issues since late 2014 trucks, cars, anything and it always will be, it's a crappy transmission with crappy programming.
01-23-2019, 11:16 AM
#9
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statistics please
" the A8 issues are not specific to a certain model of car, it is a pandemic "
Pandemic means pervasive and widespread over the entire fleet in this case. Based on the A8 thread in the general section it appears for the C7 to not be a huge issue and mostly dealt with by changing fluid. Some major mechanical failures but mostly shudder and software issues. Did I miss something? Without data the comment is meaningless.
My interest stems from the fact that I bought my wife a 2019 GS for Christmas
Pandemic means pervasive and widespread over the entire fleet in this case. Based on the A8 thread in the general section it appears for the C7 to not be a huge issue and mostly dealt with by changing fluid. Some major mechanical failures but mostly shudder and software issues. Did I miss something? Without data the comment is meaningless.
My interest stems from the fact that I bought my wife a 2019 GS for Christmas
01-23-2019, 06:12 PM
#10
Appears to be limited
Looking at the spreadsheet it does not seem to be a huge list. Also seems like early A8 years make up a lot of the cars listed, only see one 2019. Not sure Pandemic? Also seems Range device could be huge help as eliminates the V4 mode altogether.
01-23-2019, 06:24 PM
#12
see link.
https://rangetechnology.com/
I used on my 2014 C7 flawlessly. They sell for 2019 as well. Only downside is you have to remember to remove at ignition shut off or will drain battery if not using car within 2-3 day intervals. I connected to an adapter that had a built in toggle on/ off switch. That allowed me to leave it plugged in and just turn off the toggle switch when shutting ignition off.
I used on my 2014 C7 flawlessly. They sell for 2019 as well. Only downside is you have to remember to remove at ignition shut off or will drain battery if not using car within 2-3 day intervals. I connected to an adapter that had a built in toggle on/ off switch. That allowed me to leave it plugged in and just turn off the toggle switch when shutting ignition off.
01-24-2019, 12:19 AM
#13
Melting Slicks
This is no longer a problem, I leave mine in all the time, no issues.
01-24-2019, 12:35 AM
#14
https://rangetechnology.com/
I used on my 2014 C7 flawlessly. They sell for 2019 as well. Only downside is you have to remember to remove at ignition shut off or will drain battery if not using car within 2-3 day intervals. I connected to an adapter that had a built in toggle on/ off switch. That allowed me to leave it plugged in and just turn off the toggle switch when shutting ignition off.
I used on my 2014 C7 flawlessly. They sell for 2019 as well. Only downside is you have to remember to remove at ignition shut off or will drain battery if not using car within 2-3 day intervals. I connected to an adapter that had a built in toggle on/ off switch. That allowed me to leave it plugged in and just turn off the toggle switch when shutting ignition off.
I considered a Range unit for my C7 Z06 A8 that had hard shifts up and down also lurching at stops. My problems were resolved at the dealer, however, after I read TSB calling for TCM reflash for A8's experiencing the described problems.
01-24-2019, 07:22 AM
#15
Range website says to remove if using car sporadically
Hi,
With respect to leaving it in all the time...See the company’s own website under “installation Q&A,” it says to remove the device if not using the car frequently. If it’s your daily driver you are fine. If use car sporadically the device drains the battery over time , so you need to remove it. It will not void your warranty, simply remove device before bringing to dealer for any service. Product does not rewrite any factory ECU settings.
With respect to leaving it in all the time...See the company’s own website under “installation Q&A,” it says to remove the device if not using the car frequently. If it’s your daily driver you are fine. If use car sporadically the device drains the battery over time , so you need to remove it. It will not void your warranty, simply remove device before bringing to dealer for any service. Product does not rewrite any factory ECU settings.
09-12-2019, 04:33 PM
#17
09-12-2019, 04:44 PM
#18
You don’t need data. Just read the bazillion threads on this forum. Then just go over to the biggest Silverado forum and look there. Then try a Cadillac forum. After you’ve looked there, drop into your biggest Chevy dealer and talk to the service department. You’ll find that they do this stuff on Silverados, Tahoes, Suburbans AND Corvettes every week if not every single day. GM has technical bulletins. It’s very real. I promise.
11-23-2020, 12:24 PM
#20
Le Mans Master
As I understand it, the new models of the Range device have been upgraded for a while and they no longer drain the battery. This has been discussed at length in previous threads. To be certain you purchase the current model with the upgraded software version, make sure you purchase directly from Range Technology not someone who advertises slightly lower price as an authorized seller. Range also fully guarantees the unit and they will upgrade previous units, that were actually sold by them, for no charge. I believe this info is accurate but please contact Range Technology to confirm.
I considered a Range unit for my C7 Z06 A8 that had hard shifts up and down also lurching at stops. My problems were resolved at the dealer, however, after I read TSB calling for TCM reflash for A8's experiencing the described problems.
I considered a Range unit for my C7 Z06 A8 that had hard shifts up and down also lurching at stops. My problems were resolved at the dealer, however, after I read TSB calling for TCM reflash for A8's experiencing the described problems.
Pitt