Hissing/whistling coming from EXHAUST, any ideas?

[Superbuick96]

About a month ago I had my exhaust replaced on my Ranger. As soon as I took it home I noticed that a whistling/hissing noise on when getting up to speed on the highway. I don't hear the noise while accelerating in city driving, just under heavy load, heavy acceleration at highway speeds. The noise is not heard once my cruising speed is reached, and the rpms settle down. Also there has been no noticeable performance issues, the truck feels great. My mechanic is a good guy a certified mechanic at a Ford dealership, and has his own shop he works at night in. I don't want to be a pain in the [censored] if it is just a matter of tightening the clamps. I picked it up late at night, and he admittedly did not do a test run. I guess I would like some opinions, could it be that this system is just cheap, and sounds bad, or could it be a loose clamp?

 

[Donald]

Is it a certain tune? Maybe you could whistle it for us as a sound clip?

I would suspect a leak.

 

[eljefino]

Whistle usually is a clamp.

New exhausts do sometimes sound tinny before they get coated with carbon, but that's more of a pitch thing.

 

[Olas]

With the engine running, get under there and have a look. As soon as you put your eyes on it, it'll be obvious.

 

[Superbuick96]

Originally Posted By: eljefino
Whistle usually is a clamp.

New exhausts do sometimes sound tinny before they get coated with carbon, but that's more of a pitch thing.


Im thinking, hoping just a loose clap too. He did poke a small drain hole in the back of the muffler, at first I thought that's what it was. I covered it with some sealant, and that did nothing to alter the noise. I'll check the clamps when the temps get above freezing this Friday.

 

[bullwinkle]

Start it stone cold, first thing in the morning, with the hood open and look-you'll see the leak. May have to rev it a little, but the steam puff will be visible.

 

[01rangerxl]

Was the exhaust loud before replacement from holes or something? Is it possible the whistle was hidden by other noise?

I ask because my truck whistled when the cats were clogged under similar situations...heavy load acceleration, like going up an on ramp. It ran good most of the time, but was down on power, especially over 3K RPM.

If the whistle was definitely caused by the exhaust replacement, check the connection in front of the muffler and make sure it's seated right. Maybe the donut gasket was damaged. It's hard to get that connection wrong though. I had mine apart a couple of times to deal with the cats and reused the gasket with no leaks.

 

[Superbuick96]

Turned out to be a restrictive muffler, all is good now.