Squealing or siren-like sounds?

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69_340_GTS

69_340_GTS

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A727 by TCI, 340, '69 Dart. Very low mileage. I have a squeal, or almost siren-like sound when the engine is running. Have completely ruled out the p.s. pump, water pump, and alternator. Can't pinpoint the source of the noise, but it seems loudest before everything warms up. Comes and goes, and changes pitch/tone, or goes away when you put the car in gear, out take it out of gear. Someone told me it's a bad pump in the transmission. Someone else said it's a bad torque converter. Car runs and drives just fine, and I think the noise goes away when the car is moving. Loud exhaust may be drowning it out though. Any thoughts?
 
Cut your oil filter open and see if anything is in there that should not be.

Same inspection of the trans filter, if something is coimg apart filter should catch it first.
 
69_340_GTS said:
A727 by TCI, 340, '69 Dart. Very low mileage. I have a squeal, or almost siren-like sound when the engine is running. Have completely ruled out the p.s. pump, water pump, and alternator. Can't pinpoint the source of the noise, but it seems loudest before everything warms up. Comes and goes, and changes pitch/tone, or goes away when you put the car in gear, out take it out of gear. Someone told me it's a bad pump in the transmission. Someone else said it's a bad torque converter. Car runs and drives just fine, and I think the noise goes away when the car is moving. Loud exhaust may be drowning it out though. Any thoughts?
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Sounds like the front pump in the transmission is fussing. Check the transmission fluid level to be sure it is at least between the add & full mark in neutral after the trans has warmed up.
 
Fluid is at the right level. Plus it probably only has about 2000 miles on it. I suppose I could drop the pan and take a look at the filter. Just trying to get a general consensus if you guys think it's likely a tranny problem. I can't imagine anything in the engingine making a noise like this. What would? Engine oil pressure is 60-70 psi at normal driving speeds, goes down to 30 psi at idle.
 
Have you looked in the rear view for the cops?
 
69_340_GTS said:
Fluid is at the right level. Plus it probably only has about 2000 miles on it. I suppose I could drop the pan and take a look at the filter. Just trying to get a general consensus if you guys think it's likely a tranny problem. I can't imagine anything in the engingine making a noise like this. What would? Engine oil pressure is 60-70 psi at normal driving speeds, goes down to 30 psi at idle.
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TCI has had issues with their transmissions. My son bought one for his truck and it failed after a very short time. Expensive lesson. Just because it has low miles does not mean it was built properly. Some who build transmissions do not replace the bushings. They just slap in new clutches & seals and shove it out the door. They will likely survive the low warranty given on those units. If the fluid is at the correct level, then I would pull the pan and have a look at things. Might even pull the valve body and see if anything looks awry. The alternative is to have a local builder who KNOWS WHAT THEY ARE DOING go through the unit. Good qualilty clutches, bands, and seals are not that expensive. You would then have a trans that would perform as expected, and would likely last a long time.
 
I took the front cover off over the winter and checked everything. Removed timing chain. It's almost new. Did not see anything wrong with the timing chain, oil slinger, oil seal, thrust bearing, etc... (noise was there before I did all this too)
 
It is a double-roller chain with steel gears. Might be Cloyes, I don't recall. Looked perfect when I recently had it apart. There are no weird scuff marks in the timing cover or on the block, so it's not rubbing on anything. Like I said I took the whole front of the engine apart looking for this noise and found absolutely nothing. I do not see how a timing chain can scream bloody murder, randomly. You cannot pinpoint the source of this sound, it is coming from everywhere. I've heard bad hydraulic (industrial) pumps and they kind of sound like this noise.
 
Hope you've found your problem already but if not why don't you buy a cheap stethoscope? Jab it up just between the front of the trans pan at the bell housing. That's where the pump hides and should help put you on the right track. Plus those things are great to have in your tool box anywho.
 
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