I'll start out with the specs: 2004 Ford Ranger, 4.0, 4x4, 102,000 miles, manual transmission with all the stock parts from 2004, custom cat back exhaust.

Recently the Ranger's developed a problem where something is rattling when throttling down - when i get off the gas and let the motor slow down the truck. It hapens while driving, not really while I'm parked, and it is most prominent when the RPMs drop near 2,000. I may be getting the sound when accelerating as well, but it's hard to tell with all of the other noises.

The sound seems to be coming from right by my shifter, or whatever you call it. It sounds almost like a heat shield rattling, but everything seems relatively tight. For whatever reason, the heat/sound insulation is falling off of from under my truck, but it doesn't look like this would have anything in it to make this sound. Any ideas?

 

Timing chain rattle ? Maybe the tensioner is worn/weak.

 

The tensioner doesn't have much play to it, and I don't think it's the timing chian, though I have no knowledge of what that would sound like. On my ride home yesterday, I noticed that it is making the noise while accellerating as well. After putting the truck in neutral and reving the engine, I also heard the noise come up at 2,000 rpms again, it definitely sounds like its got something to do with my exhaust.

 

Heat shield. Maybe? Not the timing chain rattle the fixed that in 2004.

 

im gonna take a shot in the dark here. Did you check the cat heat shields, hangers, any clamps and where the cat pipe bolts to the midpipe? I had a comparable problem after I got my exhaust. My problem was a hanger just popped out.

 

Ford also said they fixed it in 03 but my tuck does it.

 

Honestly, I haven't gone much into detail with that yet. I've yet to look under my truck when the exhaust wasn't hot. I'll check that out next when I get a chance.

 

probably something with your exhaust..

 

my exhaust is hitting the tire carrier...or the heatr shield on the cat...