03 sierra 1500 4.3L 2wd

Brand new tranny last may including new tranny lines, lots of new parts on it including front wheel bearings, distributor, plugs&wires etc. pads and rotors are about 5 months old including calipers all the way around. New fuel filter and fuel lines. Has aftermarket led halo headlights. Has 6motnh old tires in it. Trucks in great physical shape other than typical cab corner rust. Has a multi cylinder misfire code but still starts everytime just tired of fixing it. Has no muffler just straight pipe from cats back the the passenger side dump. trying to get rid of it quick as I bought a new truck 3000obo