What could be the cause on my 06 Silverado 5.3 to have one exhaust pipe a hotter temp than the other by 50 degrees? Jim

No, you cannot flush one. No maintenance is possible. When you get that code, you may have a cat that needs replacing, or your oxygen sensor after the cat may not be reading well. Erase the code and see if or how long it takes to come back. If it reappears shortly, like 2 weeks, or 50-100 miles, you probably have a cat needing replacement. But it might help to monitor the sensor after the cat (bank 1, sensor 2) to see what it is reading. Another way to test your cat is to use a hand-held infrared thermometer. Look at the temps on the exhaust both before and just after the cat. A working cat will have hotter exhaust at its tail, than the temp before the cat. Because a working cat will be burning off hydrocarbons in the exhaust. The temp after the cat should be about 100 degrees hotter than the exhaust before the cat.

Do you have a way to read out the codes?
How do you know it's overheating? Blowing steam from the pressure release? Sluggishness? Water consumption ?
Does your fan work?
By the sounds of it it could be in limp mode, so yeah, an old reader would help here.

temp gun. rear of converter should be hotter than front of converter.power loss is also a way of knowing your converter is plugged. car seams to be under stress load sound when running..

Try a 10w 40 weight.
If you live is a hotter climate use a 20 w 50.
The old addage about "once you use synthetic oil you have to for the life of the car" isn't true.
You just can't mix the two types of oil.
Good luck,Gary

it could, on cat converters you can tell if bad by heat. the exhaust pipe temp should be hotter on the exit side and cooler on the in side, if it is hotter on the in than the out the converter is bad.

It could be a thermostat that is only opening partially or, the radiator may need to be flushed. Radiators on Jeeps are nearly too small for the application and are very sensitive to blockages. When the engine is loaded such as going up hill, is generally where any deficit in the radiator becomes evident. Some increase in temp is normal when pulling up a long grade and with a 50/50 antifreeze mix it should not boil over unless it gets very hot.
215 degrees is about 5 degrees hotter than it should be around town. "normal" is about 210, sometimes a bit less.

Sounds like you may either have a thermostat that is not fully opening or a radiator that is partially obstructed (externally or internally). If I'm correct, what may be happening is that when the engine reaches operating temperature, it is continuing to get hotter but at the point you are at, the fans are able to compensate by remaining on.
Only other possibility is that the temp sender is bad and sending incorrect info to the computer, causing it to turn the fan on.
The concentration of antifreeze in a system does not change the operating temp. What it does is prevent the coolant from boiling at a temperature above what plain water would. Your radiator cap also helps with that as a liquid under pressure will boil at a higher temp. Proper concentration is 50/50. Normal operating temp is about 210 degrees(f). (+ ) (- ) 5 degrees)
So, I'd test the coolant sensor and replace the thermostat. Hopefully the radiator won't need to come out but you may need to have it checked if neither other options work.

That does not seem too abnormal to me. I believe you have a 195 degree F thermostat, so you should probably be a bit cooler than 230 that is for sure. You have got an engine temperature sensor, should be located on cooling port on intake, you have a coolant temperature sensor on rad. Have you put in a new thermostat?

If it's equipped with an electric fan, the fan should be on when the a/c is on. If it has a fluid clutch make sure it locks up when it's hot. If fans are OK likely you have a partially obstructed radiator (internal or external).
If it is only a few degrees hotter, that is normal, providing you have a 50/50 antifreeze mix and that the temp increase is not excessive. It gets hotter because the engine is working harder...a/c compressor draws from 5-10 hp to operate.

What does the oil look like?Do a simple tune up first, plugs wires and filters. If that doesnt work Take a temp gun, measure the heat before ur converter and after at operating temperature. If ur exhaust is more than 100 degrees hotter after the converter you need it replaced. Could cause the engine to blow up.