dcm0123 15 Report post Posted February 15, 2020 It has been a while since I had one out but my recollection is threaded bolts are used to fasten the torque converter to the flex plate. If you remove all bolts you can push the converter away from the flex plate about 1/4 of an inch. The separation may be far enough so you can start the motor without the torque converter spinning if you want to try to isolate the cause of the problem. Many years ago I replaced the flex plate on my 68 302 C-4 setup with a Ford OEM flex plate. It had an identical vibration issue. I pulled the new plate out and noticed the new plate did not have a counterweight where the old one did. I went back to the Ford dealer who told be the plate was available with and without the counterweight. I would stick with an OEM plate since an aftermarket may not be balanced properly. I learned the hard way you should install the converter into the transmission then after the transmission is in place, bolt it to the flex plate. There are several splines the converter has to engage as it is pushed into the transmission which is why you have to rotate the converter to line up the splines as you push it in. You can not feel the steps and the splines if you try to engage the converter after it is mounted to the flex plate. You can easily jam the splines which requires you to disassemble the front of the transmission to free it up. Make sure both you and your garage know what year your engine and crankshaft is. As someone else pointed out different years are balanced differently. Quote Share this post Link to post Share on other sites