Dangitman, ST3500 chatter
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From: Live Oak, FL - in the woods where the creatures lurk.
Dangitman, ST3500 chatter I've had nothing but good things to say 'bout this TC, it's performed well for 20K miles w/only street races;and mostly from a roll.
In point of fact, I do mostly highway driving.
....but now I'm getting some definite chatter that I can hear and feel. It still locks up solid at WOT, but at, say, 1/2 to 3/4 throttle in 2nd and 3rd, there is a definitely a weird feel.
Not being a auto trans guru, I can't even say that what I see can not be attributed to a problem with the A4.Anyone have any input?
Like I said, the trans shifts good all the time, but at moderate throttle I can feel, more than hear, a kind of "chatter" that doesn't seem right.
Thanks for any input, folks.
In point of fact, I do mostly highway driving.
....but now I'm getting some definite chatter that I can hear and feel. It still locks up solid at WOT, but at, say, 1/2 to 3/4 throttle in 2nd and 3rd, there is a definitely a weird feel.
Not being a auto trans guru, I can't even say that what I see can not be attributed to a problem with the A4.Anyone have any input?
Like I said, the trans shifts good all the time, but at moderate throttle I can feel, more than hear, a kind of "chatter" that doesn't seem right.
Thanks for any input, folks.
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From: Bethel, CT
Re: Dangitman, ST3500 chatter Sounds like it.
Drop it into D when it does it. If that stops it, you've got it.
What to do.....
4 oz. of Lube Guard Friction Modifier available at Carquest.
A HPP III to firm up the shifts. Will minimize but not elliminate problem.
Send it back to Yank for a clutch material upgrade (if it's kevlar, they were switched to carbon/ceramic mid 2001)
Buy a new converter.
Drop it into D when it does it. If that stops it, you've got it.
What to do.....
4 oz. of Lube Guard Friction Modifier available at Carquest.
A HPP III to firm up the shifts. Will minimize but not elliminate problem.
Send it back to Yank for a clutch material upgrade (if it's kevlar, they were switched to carbon/ceramic mid 2001)
Buy a new converter.
Re: Dangitman, ST3500 chatter The chatter could be a line pressure issue or the converter clutch has glazed. If your cruise LTRIMs are positive, get them negative. If you have a ported MAF, go back to stock if you have not corrected the MAF table using Edit. The more miles you put on a chattering clutch, the less chance you can solve the problem w/o having to resurface the clutch
IF the converter clutch is glazed ( there was a post some time ago explaining what to use to deglaze clutch -try a serech )
IF the converter clutch is glazed ( there was a post some time ago explaining what to use to deglaze clutch -try a serech )
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Dangitman, ST3500 chatter PFan, I bought it in late 2001, not sure what the clutch material is.
It performs pretty solidly at WOT, and around town it's fine, but at moderate throttle the chatter is somewhat noticeable.
HPP3 setting @ 50%, shifts are quick, w/a little "kick".
Abuse "should" not be a factor, but hell, GM didn't give us much behind the engine anyway.
It performs pretty solidly at WOT, and around town it's fine, but at moderate throttle the chatter is somewhat noticeable.
HPP3 setting @ 50%, shifts are quick, w/a little "kick".
Abuse "should" not be a factor, but hell, GM didn't give us much behind the engine anyway.
Re: Dangitman, ST3500 chatter I assume its a mistype, but the converter doesn't lock in 2nd gear; only in 3rd and 4th gear.
If you have problems in 2nd gear, the issue is something other than clutch chatter. Could be another converter issue or it could be the tranny, but the TC lock-up clutch isn't used in 2nd gear.
If you have problems in 2nd gear, the issue is something other than clutch chatter. Could be another converter issue or it could be the tranny, but the TC lock-up clutch isn't used in 2nd gear.
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Dangitman, ST3500 chatter </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ragtop 99:
<strong> I assume its a mistype, but the converter doesn't lock in 2nd gear; only in 3rd and 4th gear.
If you have problems in 2nd gear, the issue is something other than clutch chatter. Could be another converter issue or it could be the tranny, but the TC lock-up clutch isn't used in 2nd gear. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks, Ragtop.
That's interesting:guess I never really noticed that before; it shifts so smoothly into 2nd, but considering the effective gear ratio and all I guess I've barely noticed it.
After reading this, I drove about the countryside (visiting various, ahem, bars) and noticed that the shudder occurs in 3rd at mostly mid-throttle.
It's one of those little things that you don't notice at first, but keeps slowly creeping up into your perception.
It would be a non-issue, except that my present income is -drastically- below what it once was, and I worry about maintenance items more.
<strong> I assume its a mistype, but the converter doesn't lock in 2nd gear; only in 3rd and 4th gear.
If you have problems in 2nd gear, the issue is something other than clutch chatter. Could be another converter issue or it could be the tranny, but the TC lock-up clutch isn't used in 2nd gear. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Thanks, Ragtop.
That's interesting:guess I never really noticed that before; it shifts so smoothly into 2nd, but considering the effective gear ratio and all I guess I've barely noticed it.
After reading this, I drove about the countryside (visiting various, ahem, bars) and noticed that the shudder occurs in 3rd at mostly mid-throttle.
It's one of those little things that you don't notice at first, but keeps slowly creeping up into your perception.
It would be a non-issue, except that my present income is -drastically- below what it once was, and I worry about maintenance items more.
Re: Dangitman, ST3500 chatter Isn't this something that is more the computer
waffling, than any strictly mechanical thing?
I've felt this once, all stock, just letting
off the pedal a bit for traffic on the on-ramp
I got this fast shuddering until I gave it
more pedal again. I read about people messing
with lock/unlock points in Edit. I think it
probably wants more separation between unlock
and lock, just like the rev limiter and any
other bistable action, you want enough dead band
to keep it from oscillating forever, or enough
over-drive to get out of the decision region.
waffling, than any strictly mechanical thing?
I've felt this once, all stock, just letting
off the pedal a bit for traffic on the on-ramp
I got this fast shuddering until I gave it
more pedal again. I read about people messing
with lock/unlock points in Edit. I think it
probably wants more separation between unlock
and lock, just like the rev limiter and any
other bistable action, you want enough dead band
to keep it from oscillating forever, or enough
over-drive to get out of the decision region.
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From: Live Oak, FL - in the woods where the creatures lurk.
Re: Dangitman, ST3500 chatter You could be right about the computer. I seem to be the only person that, after the ST3500 install, on stock tuning, had a funky 1-2-1-2 shift: that is, it would spin up the rpms' pretty fast, shift to 2nd, then quickly shift back to 1st, then back to 2nd.
I eventually had to set the rev limit to 6300, and the shift points +3 mph per HPP3 to avoid that. Unfortunately, I cannot at this time buy LS1 Edit to experiment further w/ the shift rpm vs mph. I believe that given good tuning, the problem could be solved.
And like I said, at WOT the TC performs flawlessly,at least as far as I can tell.
I eventually had to set the rev limit to 6300, and the shift points +3 mph per HPP3 to avoid that. Unfortunately, I cannot at this time buy LS1 Edit to experiment further w/ the shift rpm vs mph. I believe that given good tuning, the problem could be solved.
And like I said, at WOT the TC performs flawlessly,at least as far as I can tell.
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