Installing an Aftermarket Converter

Installing an Aftermarket Converter

Tech Tip: How to properly install an aftermarket converter

Although most think torque converter installation is a “no brainer”, the fact of the matter is, a large percentage of aftermarket converter warranties have been traced directly to improper installation. I’m not talking about your local transmission shop you supply quality rebuilt OE converters to. I’m talking about the car enthusiast that is lying on his back, in his own garage, installing the after market converter. This is the customer we need to educate. It can be as easy as a single piece of paper with eight installation steps being placed in each converter box.

Step 1: Once you have removed the converter from the box, please take a minute to make sure it is the correct application. To do this, hold the converter onto the flywheel to check that the converter pilot fits properly into the rear of the crankshaft with no excess clearance. Check to make sure that the bolt holes or studs on the converter line up with the bolt pattern of the flywheel.

Step 2: After checking the converter for fit to the flywheel and crankshaft, check the flywheel itself for cracks or excessive wear on the flywheel starter teeth. It would be a shame to go through the trouble of removing the transmission and not replacing the flywheel if necessary. We strongly recommend that you replace your stock flywheel with a heavy duty flywheel. They are available for almost all applications.

Step 3: When installing the converter onto the transmission, please pour approximately one quart of ATF into the converter before installing into the transmission. Using a light grease, coat the transmission seal, front pump bushing and converter neck.

Depth Clearance:
Chrysler-Torqueflite 727 1-1/4″ from Bell Housing to Ring Gear
GM Turbo-Hydramatic 350 1-1/8″ from Bell Housing to Pads
GM Turbo-Hydramatic 700R4/4L60E/2004R 1-1/8″ from Bell Housing to Pads
GM Turbo-Hydramatic 400 1-3/16″ from Bell Housing to Pads
GM Powerglide 1-1/8″ from Bell Housing to Pads
GM 4L80E 1-1/64″ from Bell Housing to Pads
GM 4L80ELS1 1-1/64″ from Bell Housing to Pads
Ford C-6/C-4 1-1/8″ from Bell Housing to Pads
Ford AODE 1-1/32″ from Bell Housing to Pads
Ford AOD 1″ from Bell Housing to Pads
Distance may vary either way .050″


Step 4: Install the converter into the transmission carefully trying not to damage the front seal and bushing. Once you are into the pump, hold the pilot of the converter with one hand to center the converter the best that you can, and rotate the front mounting pads in a clockwise direction. This will allow the splines and hub slots (or flats in the case of Ford type) to engage into the pump properly. You should experience two distinct drops of the converter into the transmission before it is all of the way in. At this point uses a light lithium grease (white) or equivalent and grease the torque converter pilot and crankshaft pilot so that the converter slides into the crank without binding up.

Step 5: Before installing the transmission into the engine make sure that the engine dowel pins are free of rust, and that the dowel holes in the trans are free of dirt or corrosion. Grease both lightly to avoid any type of bind-up. NOTE: If you are using a motor plate, make sure that your dowel pins are long enough. In the case of a 0.090 midplate, you can get away with using stock engine dowel pins. Anything thicker than 0.090 please purchase and install longer dowel pins.

Step 6: Locate the transmission onto the engine dowel pins and install transmission mounting bolts. The transmission housing should contact the engine block squarely. If it does not, LOOK FOR THE REASON! DO NOT attempt to draw the transmission against the block with the bolts. The converter is probably not all the way into the transmission.

Step 7: After the transmission housing bolts are tight, check to see if the converter can turn freely (except Ford applications with studs). Push the converter into the transmission as far as possible. Use a ruler or scale to check the distance between the converter pad and the flywheel. Pull converter forward a minimum of 1/8 of an inch, maximum 3/16 of an inch. Using flat washers, remove any additional space between the converter and the flywheel. NOTE: In the case of Ford applications with studs, measure from end of stud to flywheel. Tighten converter nuts and measure again. The difference should be within the tolerance.

Step 8: Finish the installation of the transmission. When finished, install four quarts of ATF in the transmission. Start the engine and immediately add two more quarts. Now you can add additional fluid to fill the transmission.

Ken Kelly
Transmission Specialties, Inc.

– Found in October 2007 Newsletter