Whoa, new motor & trans on an 07 is something occurring around 170-290k miles. What you’re describing may be codes being misread.
Recently found that having the plug wire pulled off #7 will turn ON the stabilitrack warning and have the truck run like it’s got a heavy/loppy cam. Your misfire and code needs to be treated like a clue, not a diagnosis.
A bad exhaust gasket will throw a misfire code. It’s likely the truck needs missed, regular services completed. What’s your plug wire history? It’s impossible to see if one or multiple are bad unless you pull them and check for resistance. Pulling them may cause them to fail if their old. Pulling them by the wire or without the tool will cause what you’re experiencing too.
Even a driveshaft that’s out of balance will cause a funky ride. Check out your plug wires at night, ac off and raise rpm slightly. If you see or hear arcing, that’s a sure sign. You could have one or multiple coils on the way out. The easiest way to rule out coil or plug issues is to pull one wire at a time from one coil on start up. Run worse, turn off motor, move to next wire. If a wire or coil pulled causes no change, start there.
You may find a wire that separates completely or no change by pulling a wire. That would be the bad coil or wire(s). You need to team up with a 6.2 veteran who’s got your back, not your wallet.
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