Need A Little Help On Magnaflow

davo32683 · September 14, 2007

Hey guys, I've got a '04 Ex. Cab Z71 silverado. I'm looking to just swap the stock muffler for a Magnaflow. Does anybody know what model I need? Maybe the offset numbers, size and shape? I want to try finding the muffler online to save a little $$ and take it to my local shop to get it put on.

Hope somebody knows what I'm lookin for!

cerbomark · September 14, 2007

get their number from the website and I m sure they will assist you in the proper fit.

davo32683 · September 14, 2007

I called them up and they said they don't have a program to really do that. They helped out as best they could and in our discussion we kind of figured it was the 12589 in the satin finish. Can anybody confirm?

Draenor · September 14, 2007

I do see how they can't help. Just see what their regular catback system uses, and that should be the muffler.

Chris Dubya · September 17, 2007

I called them up and they said they don't have a program to really do that. They helped out as best they could and in our discussion we kind of figured it was the 12589 in the satin finish. Can anybody confirm?

I'm pretty certain that model won't fit your stock pipes. I'm fairly certain that you have 2.25" stock pipes. I have 2.5, and am currently running my second magnaflow muffler. A few things to consider. The longer the muffler, the quieter it will be. My first was 22" long and way too quiet, maybe a 3 on a 1-10 scale. My second one is 14", and absolutely perfect, maybe a 6.5-7 loudness scale. I have the 14386 which is stainless polished, dual in - dual out, dumped (tips turned down under the truck). The same muffler for your truck (assuming you have 2.25 pipes) would be the 14385. Paid a little over a hundred for the pipe, and 30 to have it installed. Sounds really nice.