Very unnerving noise coming from beneath my car

mcate

Registered User
1st noticed it the other day when accelerating from a light. It's a knocking or clanking sound that seems like it's coming from the tranny area. I called John & he said to check the heat shields on the brakes, but they don't seem to be loose or vibrating or anything. I had it up on ramps tonight & tried to isolate where it was coming from. I didn't see anything loose. Can't hear it at idle, but I can when revving the engine above 2k rpm or so. My worst case scenario is tranny or torque converter, but it shifts & runs fine. I have to fly to Jacksonville, Fl tomorrow, but I'll be back Friday. I'll bring it to Jenros Saturday.
 
I had a noise like that too once. I had my tranny rebuilt and replaced the converter and it doesn't do it any more.
 
rickbtbird said:
I had a noise like that too once. I had my tranny rebuilt and replaced the converter and it doesn't do it any more.

That's what I'm really afraid of because it definitely sounds like it's coming from the converter. The car's only got 42k miles on it.
 
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Well, I'm back in town & I was out driving it earlier today. I'm starting to wonder if I didn't get some bad gas, or if I might've accidentally put 87 in it last time, because it might be spark knock. It doesn't really sound like spark knock to me me from what I remember when I was younger, but the symptoms are right. It only does it under load, like accelerating from a light. I had just under 3/4 of a tank, so I topped it off today with 93. It's still doing it, but I only had room for 5 1/2 gallons. Might not've been enough to make much of a difference. I'll bring it to Jenro's tonight & let everyone listan to it.
 
Engine/spark knock comes from the engine bay and transmission noise comes from under the car. When they droped the pan on mine it had a bunch of parts in the bottem of the pan :eek:. I had it rebuilt and the noise went away.
 
rickbtbird said:
Engine/spark knock comes from the engine bay and transmission noise comes from under the car. When they droped the pan on mine it had a bunch of parts in the bottem of the pan :eek:. I had it rebuilt and the noise went away.

Was the tranny operating right at the time? Mine shifts fine. We all listened to it tonight & everyone pretty much believes that it's just something loose & rattling underneath the car. Hopefully tomorrow I'll get it up on ramps again & get a good look at it.
 
The noise was on going for about a year. Also, mine use to occasionally slip down shifting from OD to third with light throttle. It sort of sounded like something stressing rapidly tapping under the car when I got on it from a slow start or stop. The tranny finally blew at a stop light after a run down I90 at about 110mph for about 12 miles at 5:30am after dropping the ole lady off at the air port (I was on my way to Denny’s). I wasn't surprised it went as it had over 90k on it. These AOD's just don't last on these cars. I know a lot of people that have had to rebuild/replace them. From what I understand, even the AODE had problems. If anybody has over 100k on theirs and it’s original, then I’m willing to bet they baby it.;)
 
I think I found it

Just put it up on ramps & crawled underneath. I started bumping things with my hand & the 2nd thing I bumped was the passenger side catalytic converter. There's definitely something rattling around inside. I don't have factory converters. They're the straight-thru kind, purchased from Chesapeake Rim & Wheel when I upgraded my exhaust back in spring of 2003. I wonder if there's any warranty?
 
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Picked up 2 Magnaflow cats from Chesapeake Rim & Wheel for $138. Took the car to Mizer where they refused to install them, saying that they're illegal & they could be fined $10,000 for doing it. I showed them the receipt from 3 1/2 years ago where they did it, but no matter. Anyway, I then took the car to Oceana Muffler, & $50 later all is well.
 
Don't they look at them during state inspection? If not, then I could've gotten away with deleting them. Damn, never even thought about that! And Indiana doesn't even have a state inspection.
 
if they don't have any reason to look under the car,like an exhaust leak,they don't.the tubes would have been cheaper than the new cats,i paid $120 delivered from wynn carter,aka texas thunderbirds., and they fit great!
 
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