Jump to content

Tranny issue.


lbhskier37

Recommended Posts

I'm posting here to see if anyone has an opinion on whether my car is screwed. I have a 1992 Buick Regal Custom with the 3.1L, so I am not sure which transmission that is. (its the 4 speed auto I know that)

 

My symptoms are this, when I am in overdrive, but kinda on the low rpm end of it, like 45-53mph, if I gas on it just a little bit I get kinda a shudder-like slip. It does this usually if I am following some (insert profain name) idiot who it doing like 50 in a 55, and get to a hill and start falling back and have to gas on it just a little. If I back off a bit so I am holding speed or just barely accelerating, the shudder/slip will stop. If I gas on it hard, it will also stop. So this shudder/slip never happens if I gas on it early and accelerate to highway speeds, only when I accelerate really softly in that low end of overdrive.

 

So I don't know that much about automatic transmissions, but just from guessing, to me it feels like at those low rpms its not building up enough hydraulic pressure for the clutches to hold (this is probably totally wrong in my understanding of how these things work).

 

So here are the details, car has about 130k on it. I put about the last 35 or 40, almost totally highway miles, but I have never changed the fluid or filter. The previous owner may have, or maybe not. The fluid is a brown with a little red tint to it. It doesnt smell like the burn smell when my last tranny puked, the fluid kinda smells like dirty engine or asphalt smell.

 

So my first question is, is changing the fluid going to leave my transmission totally useless and disabled, or is that an old wives tale? Because it currently gets me to work and back, but if changing the fluid is going to make it puke right now, I dont want to do it. Secondly, is this thing going to puke soon? Is it something that can be fixed that may be doing this?

 

Any help from all you experts would be awesome!

Link to comment
Share on other sites

Alrighty, first off, your transmission is either a 4t60-E or a 4t60.

 

Most likely you are experiencing the Torque Converter Clutch releasing, or at least trying to. Basically it's an infamous switch that locks up the torque converter for increased efficiency. Unfortunatley, they often get clogged and fail to release until the transmission cools off. If you have had issues with the car dying after coming off the freeway, that would narrow it down further. Search for TCC and Torque Converter clutch, you can just unplug it if that turns out to be a bigger problem.

 

Lastly, no, a fluid change is highly reccomended along with a filter change. You might be confusing a transmission flush with changing the fluid after dropping the pan (granted, flushing is the only way to get rid of all the old fluid). On high mileage transmissions flushing can be risky as it may break old seals, etc.

 

If you don't think the filter has been changed, I'd most definatley change it and put in new fluid, THEN try to narrow down your problem.

 

Edit: I didn't see that the fluid was brown, as far as color goes, brown is typically from extended use; bad but not anywhere near as bad as black or pink. Drop the pan and change the filter and fluid. There's a writeup in the FAQ's I think.

Link to comment
Share on other sites

Both my regal and my cutlass do this a bit too. Its most likely just the torque convertor that is shuddering. Tell you what. Next time you notice it happening, apply the brakes just enough to trigger the brake lights. This will cause the Torque convertor to unlock and the problem should dissapear.

 

And as for the fluid, I would just drop that pan and change the filter. I wouldn't bother flushing it out unless its absolutly necessary.

Link to comment
Share on other sites

Ok, I still haven't had time to change the fluid (will be done over the 4th when I have time off). But I did unplug that 5 wire harness going to the front of the transmission. The TCC now doesn't engage, so it runs on the highway at a couple hundred rpm higher, but my shudder/slip is gone!

 

So on to fixing that, is there a chance that the fluid change will cure the TCC sticking, or will I most likely have to change the solonoid? If I have to change the solonoid, how bad of a job is that?

Link to comment
Share on other sites

you have a 4t60. often, a slip condition means that alot of work would have to be done, it may be time for a new torque converter, and even a rebuilt transmssion.... then again,. even though it might suffered a little slip, it might still run forever that way. Thats to say I wouldn't do anything but a fluid flush until the tranny completely dies.

 

also... if you know that you are going to be cranking low RPMs behind someone, you can always shift to regular drive!!!! try that and keep us posted.

Link to comment
Share on other sites

Ok, I still haven't had time to change the fluid (will be done over the 4th when I have time off). But I did unplug that 5 wire harness going to the front of the transmission. The TCC now doesn't engage, so it runs on the highway at a couple hundred rpm higher, but my shudder/slip is gone!

 

So on to fixing that, is there a chance that the fluid change will cure the TCC sticking, or will I most likely have to change the solonoid? If I have to change the solonoid, how bad of a job is that?

 

The solenoid is on the transmission valvebody, so you don't have to dissasemble too much tranny-wise to fix it. However, if you look, the transmission mount covers up the entire cover, so you need to drop the tranny to remove it. (I think, I'm not that familiar with the 4t60) I'd just leave it if you really don't want to pay much.

Link to comment
Share on other sites

y car has been running around for 2+ years since I've owned it with the occassional shudder...new fluid and filter helped a bit, though the problem is still there. i'm just gonna drive it till is grenades

Link to comment
Share on other sites

Update.

 

I changed the fluid and added a can of that lukas tranny fix stuff. Damn that stuff is thick, kinda scared me adding it, but I did anyways. When I dropped the pan I could see that I was wrong and it wasn't on the original fluid. The pan looked pretty clean, so I am guessing it was changed at the dealer before I bought it (45k ago). I plugged the TCC back in to see if that cured it, but it still seems to shudder a bit. It does seem like the TCC engages at a higher RPM now at least. I will probably leave the TCC plugged in, unless do you guys think that having the TCC slip once in a while will screw anything else up in the transmission?

Link to comment
Share on other sites

You don't have to drop the trans to replace the TCC. You could also consider pulling the drivers suspension knuckle out along with the splashguard, and doing it that way.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...