2015 Sierra Dash warnings like crazy, can’t find the problem please help

David Ottenbacher · October 22, 2021

Hello, for the past two years my truck (2015 Sierra 1500 All Terrain) has been intermittently flashing service lights saying the to service ABS, to service stabillitrac, and to service parking sensors. This would happen a few times a month and would immediately go away and I would think that it was just an annoying bug. But since about a month ago, when making low speed left turns, as well as any size bump, caused it to happen. This worsens into ABS light and stabillitrac light on for one day. While this happened you could feel the ABS pumping at when braking normally. This too went away the next day. I took the truck to the dealer for a diagnostic and told them all of this as well. After the $190 diagnosis they said it was the following codes (attached photo)

C0035-04, C0040-04, and C0035-0F.
they told me both front hubs were bad and needed replacement. They wanted $1800 for parts and labor. I told them thank you and paid the diagnosis and took the truck home. After the dealer the trucks electronics and 10x worse. Now the ABS and Stabillitrac lights stay on permanently, the brake light dings and flashes with any turn of the steering wheel. Also getting constant service ABS, service trailer brakes, Service stabillitrac, and reduced steering assist. I bought both front hubs and wheel speed sensors. I installed them and torqued everything back to spec. After reconnecting the battery and taking a test drive nothing had changed. I took the top panel from the dash off and did the ground mods. Again, no change. I’m going crazy trying to find the problem. I the. Took the truck to autozone for a code read. It still says the same three codes and it did, even after replacing the parts and sensors the dealer said would work. If anyone knows what the cause is it would be much appreciated. Thanks in advance, Dave