Although there appears to be nothing wrong with the way it works, the automatic tranny in my '86 GT often makes a sound like a rainstick. What the heck is going on?
I have an audio file here of a rainstick that sounds very much like what my tranny sounds like. Is there anyone who could host this 146kb MP3 file on their server so that I could link to it in this post. Please let me know, thanks.
[EDIT] Ok, after a bit of fiddling around (thanks guys!), here is a rainstick that sounds (somewhat) like my transmission. If the rainstick was "tipped" a little less (to slow down the falling "pebbles"), it would sound even more like my tranny.
[EDIT] On March 24th I hosted my audio file at another site after the original link expired. I've since edited my posts in this thread to reflect this change in the link to the audio file.
[This message has been edited by Patrick (edited 03-24-2009).]
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09:42 PM
PFF
System Bot
BlackGT Codde Member
Posts: 1107 From: Gallup, New Mexico Registered: Mar 2008
tell me how and i might be able to host it. (dsl rocks )
I can email the audio file to anyone who would be able to host it. Then as long as I know the "address" I can use PFF code here to directly link to it. A little audio player opens up and the sound is heard.
For anyone who doesn't know what a rainstick is, there are examples on YouTube. However, I wanted to post a link to a particular audio file because rainsticks can sound very different depending on how they're made and how much they're "tipped".
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09:51 PM
Patrick Member
Posts: 37685 From: Vancouver, British Columbia, Canada Registered: Apr 99
If the sound is coming from the trans and not the engine or exhaust; drop the trans and rebuild it. With noise from a gearbox its only a matter of time before the trans goes out. Is the sound heard at all speeds?
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite. 87GT - 3.4L Turbocharged engine, modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
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10:05 PM
Patrick Member
Posts: 37685 From: Vancouver, British Columbia, Canada Registered: Apr 99
The sound isn't all that loud, and I can only hear it if I'm outside or under the car (or if I'm in the car and close to a wall or a parked car and the sound bounces back). It seems to make the sound only while in gear, but it doesn't appear to always make the sound while in gear.
[EDIT] Because it's difficult to hear, I now realize (after listening carefully today) it probably makes the sound ALL the time, but more so while in gear.
Before I hollowed out my cat, I thought it was stuff rattling around in there. Then I thought it might be cat guts bouncing around in my muffler, but the sound is not coming from there. When I'm under the car, it certainly appears to be coming from the tranny.
[This message has been edited by Patrick (edited 01-16-2009).]
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10:10 PM
BlackGT Codde Member
Posts: 1107 From: Gallup, New Mexico Registered: Mar 2008
You can try dropping the pan and changing the fluid and filter first. I've had a few trans problems that went away after I did this. Also make sure that the trans fluid is up to the full mark when the engine is warm.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite. 87GT - 3.4L Turbocharged engine, modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
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08:07 AM
BlackGT Codde Member
Posts: 1107 From: Gallup, New Mexico Registered: Mar 2008
i was going to say this morning that it could be getting a little bit of air and causing miniscule bubbles in the fluid pump. if the filter was clogging the fluid then it theroetically can cause this also: edit: sorry for making the first part of the page so difficult to read
[This message has been edited by BlackGT Codde (edited 01-14-2009).]
Also make sure that the trans fluid is up to the full mark when the engine is warm.
The fluid level is good and it doesn't look or smell bad. A fluid and filter change probably wouldn't hurt, but I was reluctant to do so if the tranny was about to pack it in.
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05:44 PM
Patrick Member
Posts: 37685 From: Vancouver, British Columbia, Canada Registered: Apr 99
Hmmm.... why would you want to fix that? It's very soothing
Heh heh...
Seriously though, there must be a tranny expert out there who could explain just WHAT it is that creates that weird sound, which as I corrected in an earlier post, appears to only occur while the tranny is in gear.
[EDIT] Because it's difficult to hear, I now realize (after listening carefully today) it probably makes the sound ALL the time, but more so while in gear.
[This message has been edited by Patrick (edited 03-24-2009).]
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05:47 PM
Jan 15th, 2009
BlackGT Codde Member
Posts: 1107 From: Gallup, New Mexico Registered: Mar 2008
that tranny will make the sound you describe in a few situations .1. after a fresh rebuild while your filling it with fluid air in the valve body will vibrate the valves thus the noise. 2 when the filter gets cloged the fluid flows through any space possible and can make wierd noises .3. when your fluid is low also the pump will create a vortex in the pan under the filter sucking in air makeing the noise . like all have said check the fluid , and give her a fluid and filter change see if it helps . dakota
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03:55 PM
Patrick Member
Posts: 37685 From: Vancouver, British Columbia, Canada Registered: Apr 99
that tranny will make the sound you describe in a few situations...
1. after a fresh rebuild while your filling it with fluid air in the valve body will vibrate the valves thus the noise.
2. when the filter gets cloged the fluid flows through any space possible and can make wierd noises .
3. when your fluid is low also the pump will create a vortex in the pan under the filter sucking in air makeing the noise. like all have said check the fluid , and give her a fluid and filter change see if it helps .
Dakota, thanks for your feedback.
1) Is it actually the valves rattling around inside the tranny that I could be hearing? Yikes! It's definitely not a fresh rebuild, as the GT had been sitting for six years before I bought it in early Spring last year. The tranny did not make this noise when I bought the GT or for the first few months I drove it.
2) Any chance that simply sitting for six years could contribute to the filter getting semi-clogged?
3) The fluid is right up where it should be on the dipstick when warm. It looks and smells good, and the tranny seems to perform just fine. However, I suppose it definitely wouldn't hurt to drop the pan and change the filter. Anybody know offhand the amount of tranny fluid that needs to be replaced when the pan is dropped?
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08:11 PM
Mar 15th, 2009
Patrick Member
Posts: 37685 From: Vancouver, British Columbia, Canada Registered: Apr 99
I've noticed that unfortunately wherever BlackGT Codde stored the MP3 file of the rainstick sound that it's no longer there.
If anyone else has a place to store a short audio file so people can access and hear it, please let me know and I'll email it to you.
[EDIT] On March 24th I hosted my audio file at another site after the original link expired. I've since edited my posts in this thread to reflect this change in the link to the audio file.
[This message has been edited by Patrick (edited 03-24-2009).]
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12:49 AM
PFF
System Bot
Patrick Member
Posts: 37685 From: Vancouver, British Columbia, Canada Registered: Apr 99
Hmmm.... after advancing my ignition timing and setting it "by ear" (as discussed in This thread), the rainstick sound my tranny was making mysterically disappeared. However, a few days later it just as mysterically reappeared. I had done nothing else to the engine/tranny.
If anybody can explain what's going on with this automatic transmission, I'd love to hear about it.
[This message has been edited by Patrick (edited 03-24-2009).]
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12:59 AM
May 8th, 2009
Patrick Member
Posts: 37685 From: Vancouver, British Columbia, Canada Registered: Apr 99
I dug this thread up because I wanted to mention that the weird “rainstick” sound stopped, apparently all by itself.
I dropped the tranny oil pan anyway because I had bought a filter for it and I wanted to have a look in there. Absolutely no evidence of metal shavings, and the only evidence of any kind of wear was a very thin layer of grey-black “dust” on the bottom of the pan. I suspect this tranny had been serviced/flushed at some point before I bought the GT.
I had read that there was supposed to be a magnet of some kind sitting in/on the pan to attract iron particles, but I saw no magnet or any evidence that a magnet had ever been sitting there.
Anyway, after I changed the filter, buttoned it back up, and refilled with ATF, the tranny works and sounds just fine.
It’s odd how the “rainstick” noise would appear out of nowhere for months, and then just as mysteriously disappear.
)
