WOW excellent ! I had done some reading on this isuse and read about a set screw that works its way loose and i guess that is it....
so how does your cam look? any damage that you can tell?
I am seriously considering preemptively replacing my lifters....

 

The cam looks fine, I bought the manifold so I'm replacing that and the 4 lifters in the #1 cylinder bank (1&7). The pins are pushed out with the spring in the photo that locks the lifter so it operates normal, oil pressure from the manifold when activated flows down through the two ports andholds the pin in that silences the top half of the lifter with the spring so your valves are open no compression in that cylinder or fuel. Those pins were stuck on mine I tapped it and the piun and spring came out but the other side i had to tap out with a punch. There is no set screw it is all done with oil pressure, you'll see a ring with a small oil port that activates it.
Chaz

 

If you happen to take any pictures of your dis-assembly assembly process we'd love to see them

 

Same thing used to happen to our 2007 Tahoe. When the light came up, we took it to the mechanic (close to our house), he ran the code and it turned out to be the throttle control actuator, he said a sensor goes wrong and we replaced the whole part, the reduced engine power and the lights no longer appear on the message center. Seems to have fixed the problem for us.

 

Try replacing the Terminating Resistor located in a cross channel under the spare tire. That usually fixes the problem. Also could be loose ABS connector near the top of the rear shocks or the wire can be compromised by the brake rubbing against the wire. good luck

 

ABS stablitrak service lights on how do I fix this issue
Should my truck not be shifting into gears
Chevy silverado 08

 

This has happened twice to my 2007 Suburban with 150,000 miles on it. The throttle body needs to be cleaned. All it'll cost you is a can of brake cleaner.

 

Welcome to the forum...
there can be multiple causes of the ABS stabilitrac service lights... the shifting could be because the engine/transmission has gone into "limp" mode
Sometimes just shutting the vehicle off for a few minutes and starting back up will recover from the limp mode...( but it still needs to be addressed) If it does not there maybe something more serious.

 

I had the same thing it was a bad RR wheel sensor

 

FINALLY FIXED, "SERVICE STABILITRAK & TRACTION CONTROL DIAGNOSTIC PROBLEM:
"SERVICE STABILITRAK",
"SERVICE TRACTION CONTROL",
"HARD SHIFT 1-2 GEARS"-(STABILITRAK TURNING OFF-CLUNK NOISE)
"STABILITRAK OFF",
"TRACTION CONTROL OFF"
----------------------------------------------------------------------------------
CAUSE:
FUEL WAS 45% ETHANOL @ 85-(COSTCO GAS)-COMPUTER WENT INTO LIMP MODE CAUSING (AFM) TO GET STUCK AND NOT RESET COMPUTER.
----------------------------------------------------------------------------------
SOLUTION:
DRAINED & CLEANED GAS TANK-
CHANGED FUEL FILTERS (*ONLY IF NEEDED)
CLEANED INJECTORS-
RESET COMPUTER-
FILLED GAS TANK WITH NO ETHANOL- (Ethanol-free gas stations in the U.S. and Canada)
TOTAL AMOUNT WITH TAX: $444.86
----------------------------------------------------------------------------------
REFERENCES
(STABILITRAK CLUNK NOISE): https://chevroletforum.com/forum/sil...uestion-47580/
(AFM)-Definition: Active Fuel Management - Wikipedia, the free encyclopedia
(ETHANOL): Common ethanol fuel mixtures - Wikipedia, the free encyclopedia
(GAS STATIONS WITHOUT ETHANOL): Ethanol-free gas stations in the U.S. and Canada