Our Community is 940,000 Strong. Join Us.


1995 LeSabre - Transaxle / TC Chatter or Rattle


timrice
04-24-2004, 12:57 AM
I have a '95 with 113K on it. Have had it since last Aug., and it's had this brief rattling noise since I bought it with 107K. The noise comes from the front driver's side of the engine compartment. It's usually brief--just a second or so--and seems to me to occur at the same time the torque converter is locking up. It occurs generally between 35 and 45 mph, though if I put my foot in it, it will happen at a higher speed, and the duration of the noise is shorter. In slow city or residential traffic, I spend a lot of time in this speed range, so it gets annoying hearing that chattering noise over and over.

I'm pretty well convinced it's not CV joints, since the boots look good and it doesn't make grinding noises in turns.

I have considered disconnecting the electrical connection at the torque converter to see if that makes the rattle go away, thus narrowing the source of the noise down to the TC. See any problems with that?

Can't say the noise has gotten any worse over the past 8 months/6K miles, but it's consistent. Trans fluid looks and smells normal.

What do you think? Is this the TC, and if so, is it just a matter of time before it goes?

auto trainy
04-26-2004, 06:22 PM
From what your saying I dont think its in the TC,I would go to a couple of transmission shops and have them test drive it and get a couple of opinions (go to a few).

auto trainy
05-07-2004, 04:50 AM
Check for a possible exaust vibration (just a thought)

TwoNorthern
06-02-2004, 08:23 PM
I have a 97 LeSabre with a similar problem. It has been at the Buick dealer's shop for the past 10 weeks. My original problem was a failure to shift at all. They performed the necessary repair but when I got the car back, I experienced what I refer to as a "shudder" at any speed that would last for only a few seconds. After they finally called Detroit, the explanation I got today is that GM made some "software" changes for this vehicle's transmission that were meant to improve mileage at the expense of an introduction of this "shudder". I don't know whether to believe them or not since they've already done a tuneup, replaced the front and rear shock/struts, and changed the motor mounts but it's the only remotely feasible explanation to this point. It might be a similar situation that you are experiencing. Good luck.

arnstr
08-28-2004, 03:23 PM
I have the same on 92 lesabre not related to hills(load) bumps or turning I'm thinking exhaust heat trim or brake shield rattling, maybe a rock stuck somwhere, seems to be alot of dirt & rocks under mine, bought used month ago and having fun(?)

timrice
10-15-2004, 05:21 PM
Thought I'd update this thread. Here it is about six months after my original post, and my car is still doing the same thing. I have to admit that it's not gotten any worse, and driveability is unaffected. This and my inherent cheapness have thus far won out over having it taken in and letting someone try to figure it out. It's just really annoying to have to hear that rattle / ticking noise as the torque converter locks and unlocks. I think the idea that GM made software changes that resulted in the shudder isn't related to what I'm experiencing. (Seems like an engineer who added a shudder in the shift quality and excused it by saying they were improving mileage should be laughed right down to the unemployment line.) I say that because the car doesn't shudder. It's a sound more than a "feel." Also, I have a '91 Park Ave., and it's starting to make the same noise now, albeit very faintly. I would think that if it's exhaust rattle, you could get this noise sitting in P and revving the engine. You can't. And the noise always happens in the same speed range, +/-5 mph. It's completely predictable.

wallus
12-15-2004, 10:57 PM
I don't know if you have disconnected that trans plug yet, but if you did you must have had a real thrill when you drove it.
I was wondering if this noise happens when the torque converter clutch locks up and again when it disengages. If so then it's possible you are hearing a slight pinging from the engine as it takes that rpm drop and then again as disengages.
I'm not going to pretend I know exactly what could be causing that(if it is a ping I mean) but it could be engine temp too high, or a sensor not "sensing" changes in rpm changes quickly enough. Knock sensor maybe? Hope this helps.

timrice
12-16-2004, 10:07 PM
No, I never did actually unplug it. I took a look at a wiring diagram for that plug (Alldata), and decided I didn't want to do that. So I keep driving it. I suppose it *could* be engine ping, but it always sounds like it's coming from the front left part of the engine compartment. This is one of the more annoying things I've ever experienced on a car. I am fairly convinced that the noise always happens with torque converter engagement. I wonder too if the TC is dropping in and out, and I have never thought the transmission shifted all that smoothly. If a new car did this, it would be back at the dealer pronto with a demand that it be fixed. But it's a '95, so I suffer with it.

buickmastermind
12-17-2004, 08:06 AM
I wouldn't be surprised if the torque converter was dying. It's very possible that one of the clutch plates inside is sticking, or that a spring has broken. It could also be internally off balance, loose, or grinding on the gear. I highly doubt that it is engine pinging. Especially if the tranny doesn't shift too smoothly. You earlier stated that the fluid was red/no smell. Is that still true? Also, inspect it under a bright light to see if there is any evidence of small metal flakes in the fluid.

huey286
12-21-2004, 02:55 PM
I have a '91 Les. that has done that shudder for 3 years. It's the TCC solenoid, it sticks. I've unplugged mine to check, then it doesn't make noise, but the converter clutch never locks, which, in hot weather, may blow out front trans seal, because of overheating from clutch always slipping. A shop told me they would replace it for $400. Also can check by, when it makes noise, step lightly on brake, this disengages the clutch. To replace solenoid, must remove left drive axle,etc. and side pan of trans, quite a job to do in the driveway. So, I plugged mine back in and live with it, it's not so bad a noise if you know what it is. Good luck, Huey

huey286
12-21-2004, 02:59 PM
I have a '91 Les. that has done that shudder for 3 years. It's the TCC solenoid, it sticks. I've unplugged mine to check, then it doesn't make noise, but the converter clutch never locks, which, in hot weather, may blow out front trans seal, because of overheating from clutch always slipping. A shop told me they would replace it for $400. Also can check by, when it makes noise, step lightly on brake, this disengages the clutch. To replace solenoid, must remove left drive axle,etc. and side pan of trans, quite a job to do in the driveway. So, I plugged mine back in and live with it, it's not so bad a noise if you know what it is. Good luck, Also, if you check your OBD trouble codes, I bet you have a code 39 - torque converter clutch Huey

Add your comment to this topic!