This is post that might help others out. I bought this truck with 45k miles on it and it currently has 46'500 miles on it. Here is what I've done to it so far.
1. Loss of brakes. I found the brake line on the drivers side in front of the rear tire had a hole in it. I replaced the brake line.

2. The truck started bucking under load. I replaced the spark plugs (one side was worn out), replaced the plug wires and finally replaced the coil and solved the problem.
3. Started getting more codes like lean bank #1 and cat converter below threshold. I had a mechanic replace gaskets and isolator bolts in the plastic part that sits on top of the engine.
4. I started to get a VERY LOUD squealing and smoke from the engine bay. The serp belt broke. Upon inspection the lowest left pully was completely shot and the power steering pully was not turning nice and easy. So I bought two pullies and a power steering pump and had a mechanic install them along with a new serp belt
So far no codes. Everything checks out except the evap system hasn't had a chance to do a complete cycle yet......all other systems are showing OK.

 

Almost forgot, I replaced the pcv valve and had the fuel filter replaced as well.

 

After another 50 miles, the check engine light is back on. To late tonight to have the codes read.

 

The code now is p0430....cat bank 2 below thresh.

 

Don't forget to change out the coolant and transmission oil.