Device does what it claims to do; prevent vehicle from shifting into V4 mode. This doesn't completely stop the annoying vibration that occurs between 1000rpm and 1250rpm. I believe there is some other inherent deficiency that Chevy can't diagnose or chooses not to address. This vehicle should not vibrate or shudder at a certain rpm.
Product works as described. However the install instructions are very confusing. The instructions that came with the device said to use the USB stick to down load the GT load data but the down load program would not find the USB device. I had to use the GT device to down load directly into it. The layout of the on line instructions are confusing because they mix Gm, Dodge, Ford and others together in the instruction layout.
It does exactly what I bought it for
I bought this to turn off the afm on my truck and it does exactly that. I have also been able to read an engine code with it already as well and worked great. The reason for 4 stars instead of 5 is because it seems to mess with the truck electronics while installing the tune (dash lights flashing, service stabletrak), which I don't know if its normal or not but worries me, so I will just stick with the stock tune with the afm disabled. Autoanything was extremely helpful with the purchase.