2002 Nissan Frontier Catilytic converter help

My dad had his codes scanned today on his 2002 Frontier 4wd 3.3L v6 and his cats are bad (could explain the poor MPG's and sluggishness).

He went to an exhaust shop and they told him he cannot run aftermarket cats beacause the truck will not run "at all" I know that is bullshit, the muffler guy wants to sell him stock fit cats for $300 each (it has two cats) and the cats he wants to sell him are aftermarket OE, not even Nissan OEM..

I did a google search and NOTHING turned up (guess there is no info on Nissan's compared to our Tacos??).

Anyone have experience with these trucks? I was thinking cut one cat out, and run a maganflow high flow in the place of another? Or just knock the guts out of them?

And his frontier only has 94,000 miles...and both cats are bad WOW nissan

 

i just can't believe the muffler place is telling him that if he runs high flows that the truck wont run at all...

freaking dishonest bastards...

thanks guys. I have a Cat co. high flow in my taco and have had no problems

 

after being under the nissan for about 15 mins figuring out how we are going to remove the cats to gut em out (going that route for now), I am SO glad that I own a Taco.

Everything in the nissan is jammed together, cant get a wrench on anything, and everything looks so cheezy compared to my taco.

And the torsion bar front suspension is fail...

And it appears the rear main seal has developed a slight leak (once again re-iterating that the truck has less than 100k miles on it)