My father was in the truck business, and I grew up working in GM dealerships, so I'd say I instinctively lean towards their trucks. I've had great service out of my 2004 Silverado. I drove a Colorado a couple of years ago and I thought it would be a great truck for the money, and planned to buy one when old faithful dies. Since then, I've learned about the problems with the 8 speed transmissions in many GM vehicles. Shutter, hard shifts, etc.. There's even a class action lawsuit. I've worked in manufacturing for 35 years, including one company that makes hydraulic lifters, so I know something about how OEMs deal with new product defects.
From what I understand, the reported root cause is that the original transmission fluid was hygroscopic, meaning it absorbed moisture. https://gm-techlink.com/?p=11127. I've read where people report the problem and the dealership first says it's normal, but in most cases they flush the transmission and replace it with a fluid from Mobile 1. When the problem returns, they may do it again, and if you complain enough they'll eventually replace the torque converter. Apparently some customers have been successful getting GM to give them a refund via their state's lemon law.
It's really difficult to get good information on this issue. I can't believe the fluid was the root cause. I bet many other transmissions work OK with the original fluid, so what's the deal with this one? I also heard a rumor that the torque converters were manufactured with defective material. This sounds plausible.
Long story short, I expect to hear someone report the actual root cause/causes of the defects and the corrective actions they've taken to completely resolve the issues. Then, I want to know for sure that all vehicles and transmissions built after a certain date are completely free of these problems. I mean, this has been going on for years.. They may have already fixed it, but I can't find that information anywhere on the internet. Perhaps their lawyers have told them to keep their mouths shut so they won't have to repair or replace a million transmissions....
Regardless, I still may not choose a GM when the time comes to replace my 2004, but I think it would good if someone would report on this issue.
Help me, Obi-Wan K_Scotty. You're my only hope. 😉
GMs answer is that design defects are not considered an issue when it come to recalls.
Gm says that since no one has been killed or harmed...the issue is not serious..
Lastly - GM says that these minute shudders and gremlins are to be dealt with by the customer.
Basically GM is saying they knew about these defects since 2015 and kept quiet about it....kinda similar to the Cobalt ignition key fisco I am sure you know about but far FAR more serious.. I being a GM fan also seeing all these responses would NOY even buy GM ever.
I'm happy with by 2003 Hummer H2, 2003 Chevy SSR and 2001 Camaro SS conv....
Very interesting...
This is the level of quality and care for customers we are talking about:
https://www.carcomplaints.com/news/2021/gm-transmission-lawsuit-partly-dismissed.shtml
Great article. That's some very good info.
Glad it was helpful.
The combination of that GM 8-speed and GM’s engines with the active fuel management (AFM) - and now they offer Dynamic Fuel Management (DFM) - is reason enough to avoid all those GM vehicles if folks care about longevity. I realize not everyone buys based on that criteria, but they should at least be aware.
I wouldn’t hold my breathe. We’ll never know the true root cause. The GM LS7 engines with the valve guide wear issue since 2005 - we still have no true root cause, just probable (top) causes and “solutions” from aftermarket performance shops but no one knows how long they will last before out of spec again.
