If a guy drilled a few well-placed, very-small drain holes through the lowest spots of the exhaust system, would you hear them over the normal rumble and tumble of the car's engine etc, and would it help the longevity of the exhaust system?

No idea but my 99 crown vic has holes in the mufflers and you should see the water roll out of them at start up. At 1st I thought I needed new mufflers when a buddy told me, no that's supposed to happen. I would think if you drilled them after the mufflers you'd be ok.

I've seen many people do it on exhausts (including a lot of shops). Most of the time I see them pop a hole right in the lowest spot of the muffler. It has never made any noticeable sounding exhaust leak either.

This was done by the factory I believe.

I think the tree huggers made the manufacturers get rid of the muffler weep hole due to environmental concerns. Its obviously much better for the environment if any condensation is blown out the rear of the pipes instead of just dripped upon the ground

I've done it and could not hear any difference in the exhaust note.

Friend of mine drilled some into the exhaust collector on the headers of a chevy he had. Said it was an old trick from Cali to get a car to pass emmissions.

It did get his car to pass. Seems to suck fresh air in.

My 02 Ram has a drip hole in the muffler from the factory.

My stock 340 tail pipes have them as well as the stock chrome tips and the stock mufflers. They were there to help eliminate some of the rusting issues. As many pointed out, the stock MOPARs still use them for the same reason. My Cuda leaves six wet spots when it idles in the cold. :)

My 71 GTX has weep holes in the mufflers and in the tail pipes right after bend back over the axles and come strait out.

I don't recall the tips having them, by my 69.5 RR has its original tips and the weep holes are in them.

Its part of a factory design to eliminat condensation and increase exhaust life.

Thanks for all the great information. Now I gotta get under the car with a drill.

You have one gallon of water come out the exhaust for every gallon of gas that you burn so the water has to go somewhere. The weep holes are a great idea if you just do a lot of city driving. On the freeway the exhaust gets hot and most of the water goes out as a vapor but in town it stays a liquid.

I worked at an "Exhaust Pros" shop from 95 to 01. Putting weep holes in the back of mufflers was common practice. It helps the most on vehicles that have the muffler at the back of the car. In those situations the muffler rarely gets hot enough for the water to burn off.

On a regular parts store muffler, you don't have to get out a drill. We just used an "al" and punched the hole. If you are using a stronger muffler like a Flowmaster, the case is too thick and you have to use a drill.

Any ideas on what size to use? Too small and it will plug, to big and it will be....well, too big.

I beleive E'berg recommended an 1/8th".

my 87 Diplomat had them stock, never heard any extra noise on the stock system, doubt you'd heard it with a louder than stock muffler.

Factory 69/340 swinger exhaust tip, 1/8 hole. Mike

Cool, thanks!