I was just doing my weekly inspection of the undercarriage of my 1998 F150, when I noticed water leaking from the front and rear seams of the muffler. I was wanting to know if this is normal or is it time to replace it? Any input would be welcome.

 

The water is from normal combustion and a working catalytic converter. Normally there is a drain hole in the rear of the muffler to allow the water to drain out so that the water that would normally accumulate does not rot the muffler out. Some OEM mufflers didn't come with hole. Most aftermarket mufflers don't have the drain hole. It should never leak water from the seams as this would indicate that the muffler is rusting out from the inside and may soon need replacing.