Ok lets back up here, correct me if I am wrong, its a little late at night, but this problem started after you had the transmission rebuilt? Who rebuilt your transmission? When you say you have a code for a Neutral Safety switch and your 4x4 light comes on, it sounds to me like whoever installed your transmission didn't know what they were doing and messed up the shifter adjustments.
If I were you I would bring your truck back to the place who rebuilt your transmission, because if the truck is only bogging down in 3rd gear, it could very well be an issue with the transmission itself, a band that's not releasing properly or a stuck clutch pack. I am also very skeptical about that cps, I have heard alot of horror stories with after market units. I would fork over the money for an oem unit, or look for a junkyard oem unit that is still good.

 

whats a cps and where it located.... thats not the thing the tranny will work fine it was working fine the guy that rebuilt it is a very good and i mean VERY GOOD tranny guy he does the school districts and the police departments cars also. My dad looked at it and said if it was injectors it would be popping and all even if it was revving. If it was a tranny problem i didnt think th engine would be so hesitant every now and then and wouldnt make the engine spit and sputter. I had my 02 sensor unplugged maybe that is what is throwing it off cause i member i had a bad 02 sensor and it sounded like a mean cammed camaro and ran like CRAP!!!

 

Well dropped it off at the dealership .... I really think it needs a tune up like 3 spark plug wires are melted and messed up and the fuel sync is wayyyyy outta wack !!!

 

yup, the spark plugs will cause that. Just a small crack in the wire will make you need to replace it. Always save a few of the LONGEST wires when you do a tune up. THey come in handy!

As far as the fuel synch....who did that for you?

 

The dealership is doing the fuel sync thats the only place I trust with that and besides its only a hundred bucks. And im doing the full mopar tune up my self !