P189A/P1899 Transmission Error Codes Following Lift and New Tires

Chris27012 · June 19, 2019

Hello Everyone,

New to the forum and need some help! I purchased a 2019 Silverado LT 5.3l 4x4 (new body style) about two months ago. I recently put on some bigger tires, rims and a 2" RC leveling kit. Shortly after installation, the engine light came on and the truck would not sift out of Auto to 2wd or 4hi. I'm also feeling some wonkiness in the back tires and transfer case...feels like it is stuck in 4hi on dry pavement. I had the codes pulled and something is causing a P189A and P1899 (transmission) errors to trigger. I did some research and found the issues could be a result of a speedometer calibration issue caused by the bigger tires. I was told a speedometer calibration unit should resolve the issue. I purchased an inline speedometer calibration unit from Hypertech, set the parameters and installed it. Unfortunately, the problem is still occurring. Any suggestions from anyone? Has anyone else experienced this? Thanks in advance for the help!

Thanks

Chris

Edited June 19, 2019 by Chris27012
Typo

joedekock · June 19, 2019

Nice looking truck. I have no help for you unfortunately other than to say good luck. I have a 2019 as well and with all the technology in it and to make my warranty hassle free, I am not going to do any mods to it.

cire0309 · June 20, 2019

https://gm-techlink.com/?p=11123

Chris27012 · June 20, 2019

cire0309 thanks for the information! Very helpful!

Chris27012 · June 23, 2019

Update: Looks like the timing of the engine light coming on after installing the leveling kit and tires was just a coincidence. The truck has been at the dealer since Thursday and their master tech was on the Phone with Chevy HQ for 4 hours on Friday trying to troubleshoot. They were able to get the truck out of 4wd, but it is throwing a crtical fault still. They plan to replace the BCM as they think that is what is causing the issue. They are aware of the advisory regarding the TCCM, but they don’t feel that is the issue. My service coordinator said no one there has ever seen anything like this before. I’ll keep everyone posted.

Edited June 23, 2019 by Chris27012