The 94-95 Mustangs (and other models of Fords) had a common problem. The problem was torque converter shudder. This problem affected multiple engine sizes. I know in the Mustang realm, it affected the GT and Base models (3.8 and 5.0L).
In this post I will discuss how to identify a torque converter shudder and how to replace your torque converter.
When I first purchased a mustang (back in 2003) I bought a 94 Mustang Coupe. It had a V6 and a known blown head gasket. I bought the car relatively cheap, towed it home and promptly fixed the blown head gasket.
After putting on a new set of tires, I noticed that I got this weird shaking and noise that happened around 30-35 MPH. It happened consistantly, and could be repeated. This bothered me, so I dropped the transmission pan and drained the torque converter, replaced the filter and filled the thing back up with fluid. That problem still existed. I was stumped. What happened next is a long story that resulted with my ex having the Mustang, and I never had enough time to research why it was doing it or what caused it to happen.
Flash forward to 2011 and I bought a 95 GT convertible. Wouldn't you know it, this car had that same exact symptom. This was just odd. I now termed it the "Mustang Shake." This was something that was now consistant across two cars so I figured I could fix whatever it was that caused that. (This was before I found out about the engine.)
I did some research on this and found out that this was something called a torque converter shudder. Very very common in this car and usually resulted in draining all the fluid from the car and replacing the filter and fluid with Mercron V transmission fluid. There is an additive in the Mercron V fluid that is supposed to prevent this. Note that this is what I had done to the 94, with the exception of the Mercron V oil. Had I only known... :)
Well, a little more research and I found out that there is a company that makes a product called Dr. Tranny. This is an additive that you add to your transmission specifically for fixing torque converter shudder.
Well dumping a $7 tube of this in the transmission was a lot easier than draining the fluid, so I did it. Well, what do you know, the "Mustang Shake" was gone immediately. It was amazing.
So you must be asking yourself, well why is he telling me this if the title is installing a torque converter?
So the proper fix to the torque converter shudder is to actually replace the torque converter. The problem was that the torque converter was locking up and that is what was causing the shudder. The additive just helped keep the torque converter from locking up.
Now we need to flash forward a couple more months. You will then know why. At this point I found out this engine had a rod knocking in it. The fix for that is to replace the engine. If you have been following my posts at all, you will see that I did this already. :)
To replace the Torque converter you need to do one of two different things.
Option 1: Remove the Transmission and replace the converter.
Option 2: Remove the Engine and replace the converter.
In my case, I went with Option 2 since the engine was getting pulled anyway.
If you were to choose Option 1, you will need to do a little bit to get the transmission dropped down. Make sure you have a transmission jack to lift the transmission up and whatnot. I cannot really detail this since I did not go down this route, but I can give you the 1000 ft overview.
First and foremost, you will need to drain the fluid out of your transmission. If you do not, you will have a major mess.
You will need to drop the catalytic converters or H-pipe (whichever you have). This can be done by loosening the nuts that are on the exhaust manifold/headers. (if you have the long tube headers, you may have to remove those as well, but I am not certain on that) There are two bolts on each side holding the exhaust up.
You will then need to remove the four nuts on the back end of the converters/H-pipe that connect to the mufflers. This will allow you to drop the pipes down. Note they are held in place in the crossmember. You will need to slide the bracket out of there.
Once this is finished, you can take out the driveshaft. There are four bolts that hold this on to the rear end.
Next you will want to remove the starter from the engine. There are 2 bolts that hold it on.
Remove the inspection plate and the four bolts that hold the torque converter to the flywheel.
Once you have all of this done, you will want to drop the crossmember. This will allow the transmission to dip down a bit. You will want to make sure you have a jack or something under it to hold it in place.
Lower your transmission and disconnect the Lines and any electrical plugs. You will also need to disconnect the speedometer cable at this point as well.
Lower the transmission a bit more and remove the 6 bolts that hold the transmission on to the engine. Before you remove the last bolt, you will want to raise the transmission back up so that you can keep your engine as level as possible when you break it loose.
Remove the last bolt and then break the transmission loose from the engine. Be very careful that you do not drop the transmission on the floor as you can break the alumninum casing on it and then you are paying for a new transmission.
Once the transmission is loose, you can lower your jack and remove it from under the car.
Your old torque converter will pull out pretty easily.
Make sure all of the shafts are securely in the transmission. Next you will want to replace the seal that goes around the torque converter end. This is not an easy fix after the fact so replace it while you are there and save yourself some trouble.
You will need a seal puller to get this out. It does not come out easily. There is a special tool that you can use to put it back in. I made my own out of some PVC pipe. The key is that you don't want to damage the seal and you want it to go in straight.
Take some clean transmission fluid and lightly coat the new seal. Put a quart of fluid in the torque converter. Whatever you do, do not install the torque converter dry.
Put the new torque converter in. You will feel it go on the first shaft or so just fine. The trick to this is that you need to get the last seal in place. This will take some patience. You need to spin the torque converter with one hand and with the other wiggle the torque converter. You will eventually feel it go on that last shaft. If you don't get this correct, you will blow your pump out of your transmission. When all is said and done, the torque converter should be between 1 1/2 and 2 inches inside the transmission edge. Trust me, you will know when this last one is on. It isn't something that "just happens."
Once the new torque converter is installed, reverse your removal and put it all back in. Something to note is that if your torque converter is installed correctly, it should be able to spin when the transmission is mounted to the engine. If you cannot spin your torque converter, you probably don't have it in all the way.
A key to lining up the transmission and engine is to use 2 long studs that are screwed into the engine block you can line those up with the proper holes on the transmission and slide it forward.
Good luck, you will need it on this one. It is not a fun job.