1992 with magnaflow
 

my 1992 i got from my dad has a magnaflow muffler but i have pretty much no power going up hills. the muffler looks like it was jerry rigged on the pipe so im thinkin it wasnt made for my truck. think its not putting out enough back preasure to give me the power i should be getting? btw its a 3.0 v6 engine