I'm planning on buying another universal magnaflow cat next week for my truck. I just can't bare it anymore, it's so obnoxiously hummy inside my cab at all times, it's making me ill. But I had question. I have a 3" exhaust. Should I get a 3"in/out? Or a 4"in/out? Just wasn't sure what size I should go with. Also, do you guys think this will considerably lower the obnoxious drone I'm getting through the cab right now? Thanks.

 

Was the cat gutted when you first got the truck? If no, expect what you had then. I didn't follow your muffler swap thread so im not sure what happened there. I as well as you can vouch for the super 44 drone. I can assure you that going with a cat will muffel the sound more, but idk about the drone. If you do replace, I would keep it 3" in / out.

 

I have a 3" in/out but that's on my stock exhaust. Well, that parts basically stock. I had to have a reducer used to get it down to a 2.5" out. I would go with the 3" in/out if you have a 3" exhaust. A 4" in/out would be too big and you'd have to use reducers.

 

Don't mean to take over here but I have a question. My cat is rattling and wanted to know what size is the pipe where my cat is so I can just weld a new one in place. Its a 2000 Ram Sport 4x4 5.2L. Is it 2.5in or what. Any input would be appreciated. I would say go with the 3"in/out on your truck 01DodgeRam360 for my advice.

 

Post pictures. Some are different where you need that dual in single out cat or some are like mine where there is a y pipe and it goes together right before the cat so you can just cut the cat off right where it's welded on and weld in a 3"in/out cat with a reducer on the output of it. If it's like mine it will need to be a 3" in and 2.5" out but a 3"in/out works with a reducer.

 

Mine is the single in from the y-pipe. Just needed to know what size cat I need. So 3"in/out should be fine. Thanks.

 

Yup should be if you weld a reducer on the outlet of it. Any exhaust shop should be able to do that. If you can find a 3" in 2.5" out that should work perfect with no reducers.

 

If the inlet and outlet pipes to the converter are actually 3", then get a 3" in/out.

 

Quick way to check,

Hold a ruler behind the exhaust pipe exactly opposite from your line of sight. Hold the ruler from below with the "zero" end of the ruler pointing up. Push the edge of the ruler up just over the top of the pipe so you can barely see a sliver of the top of the ruler, then look at the bottom of the exhaust pipe. If you see the 3 there you've got 3" pipe. If it's halfway between 2 and 3 it's 2.5."

Always buy the exact same inner and outer diameter sizes as the exhaust. Manufacturers compensate for you if it's a slip on part.

 

Perfect, thanks guys. I'm going to re-buy the 3" in/out magnaflow cat on Monday. I don't get it, my truck just seems abnormally loud in the cab, it just hums at all times, especially loud going up hills. Hope it's going to help in balancing the drone a little bit.