AutoBanter - View Single Post - Metallic chattering sound

**E Meyer**

From your description, it sounds like a loose or damaged exhaust heat
shield.

On 4/4/07 5:39 PM, in article ,
"Chicken-Fried Steak" > wrote:

> Got a problem with my 1999 Mazda B2500 (Ford Ranger under the hood), and
> before I take it to my "plug it into the computer, no error codes, nothing's
> wrong with it" mechanic, I wanted to run it by some people that know a
> little more about vehicles. Here's the basics of my truck & the problem
>
> 1999 Mazda B2500
> 4-cylinder engine
> 5-speed manual transmission
> 130,000 miles +/-, original everything (including clutch)
> 2-wheel / rear wheel drive
>
> Problem: vehicle makes a metallic chattering sound (like someone with steel
> dentures chattering their teeth in the cold, best way I can describe it, or
> maybe like a dime rattling around in an empty beer can) intermittently.
> Sound seems to be coming from under the floor boards, close to the back end
> of the vehicle. Sound is worst when there is a load on the engine,
> especially in higher gears & when going up hill, or if I let the clutch out
> too slow when up shifting to a higher gear. Sound only happened once when
> there was no load on the engine. Engine sounds are normal, engine idles
> within normal parameters (500-750rpms), accelerates well both on flats and
> up hill. No idiot lights have come up on my panels (and this truck is like
> a nervous child, if it thinks even the slightest thing MAY be wrong, my dash
> lights up like a Christmas tree). Sound happens more often at lower RPMs
> (just before I down shift) or when accelerating suddenly.
>
> I had chalked it up to an old vehicle with a loose panel or something else
> that's pointless to worry about, until today when a friend (and former
> mechanic) said it may be something in the driveshaft and/or rear
> differential. At first I thought the worst this could be was that my
> 130,000 mile clutch is finally giving out on me, even though it feels ok.
> When he mentioned this, I had nightmare images of a bearing seizing up and
> my transmission blowing out as a result.
>
> Obviously to diagnose a problem, it helps to be IN the vehicle, but anybody
> want to shed some light on the above? Feel free to ask for more info. I'm
> just trying to get some feedback & suggestions before I take Chicken
> Little's advice about the sky (and my driveshaft) falling.
>
> C.
>
>