Hey all. First off I'm new here, obviously. I have an 01 1500 5.9
Background, I have previously gutted my cats and replaced rear O2s with sims. Long story short, I'm ready to go back to a system that is not going to freak out my computer so much. I am I the market for an exhaust system that goes from the manifolds to the muffler. I have looked online and what I see does not seem to be all inclusive as to what I need.
Anybody know a good place to start for this?

 

Magnaflow... the CAT for the 2001 5.9 shows as a 2in-1out, so the direct-fit 23258 (listed for 5.2) should work, unless this is the changeover point to the dual CAT system.

What "freak out" is your PCM having?
Most have no problems just using the simple plug saver trick... are the sims must be giving signals that the PCM doesn't like.

 

Well I am getting one code that says that the driver rear (sim) is bad so tht may be setting off a chain reaction.
I admittadly have driven the truck more than a 1000 miles or so in the last couple of years just because I didn't have to and my motivation had left me. But I need it now and it's time to get it going. I am going to do 4 new O2 sensors and new cats.

 

So you're like the '02, Direct-Fit 23959 yes?

Did you check the connection to the sim?

 

That is the system I have. Is that not typical on 01?
I had to buy a new computer a few years ago and I remember the lady on the phone telling me that I had a California computer model. I replaced it with a non California model but I wonder what else on the truck is different.

 

There are differences between cali, and everywhere else when it comes to the programming. That may be where your problems are coming from. Need the correct PCM for the system you have, before anything else you do can be expected to make any difference.

From what you describe, you do indeed have cali emissions. Need the correct PCM to go with it.

 

Cali Direct-Fit 447233 for '01.