my 96 had a bad cat. it was bad enough it left me stranded on the road. It wouldnt rev past 2k. try reving the truck, if u arent the getting the loud rumble or rpms, then it is cat. i just ordered a new one from Autozone. pretty easy 1 piece installation ypipe and all is one piece. I wouldve gone straight pipe, but i didnt know what the 02 sensors would do to the computer.

 

Echseman, that F-350 was a diesel right? Getting rid of the cat on a diesel is not that big of a deal because backpressure is not as important as it is with a gas. I'll bet he straight piped it didn't he? A straight pipe diesel sounds great, especially a Cummins.

 

it is a big block gas engine. there was no performance change from the change.

 

As far as rattling goes I really haven't heard any. I've looked around on this site and found a couple of guys that had bad cats that didn't rattle. I'll have to do some research before I make up my mind on getting rid of the cat. It might end up doing more harm than good. The oxygen sensors might mess the computer up like z28clone said. I've heard the sims don't last.

 

if you had a welder and a recipricating saw, i would say remove it and check it out. i had a bad cat a few weeks ago, and it only rattled at idle, and only every once in a while.

 

from the dodge ram FAQ sricky at the top

The best way to test the cat is to have someone in the cab rev the motor to about 2000 or 2500 rpm's and put a temp gun on the input and output of the cat. the output should be around 50 deg hotter than the input for proper cat operation. if the temps are the same, the cat is not working, if the input temp is high and the output temp is low, you have a plugged cat and you should have it swapped out immediate

 

The best way to check a cat is to go to a muffler shop, many of whom will test it for free. They cut a small hole in the exhaust, pre-cat, and connect a pressure tester. The vehicle is started and revved by one technician while the other reads the pressure. When I had mine tested, there was 10lbs of backpressure. My truck was barely able to accelerate above 50mph on a mild grade. The backpressure reading should be 0lbs.

 

Just got back from MIDAS and they did their test for free. Then they handed me an estimate for $1100 to replace! **** you, I'll go spend $300 at Advance auto for the Flow Master direct fit cat and do it myself! Cat rattles and it will not accelerate above 2000 rpm's (engine sputters and misfires). That was the longest 3 miles of my life to get home!