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Sizing Ring

AMC Engine


TH400 Transmission


AMC engines have a crank torque converter bore diameter of ~1­-13/16”. GM engines and correspondingly the torque converters are smaller diameter. In order to use the GM torque converter with the TH400 on AMC engines a thin spacer ring was employed to properly locate the converter in these applications from the factory. This is a reproduction of that part.

Product & Features

Machined from high quality steel this will replace the original part exactly which is no longer available.

Applications & Compatibility


Originally used with the AMC TH400. In theory would allow any GM converter with standard diameter to index on the crank, though spacers to the block bellhousing pattern generally position them too far to the rear to be effective.

Early AMC Cranks

early_amc_crank_flangeNot all AMC crank flange bores are the same. Early engines, 1971 and previous - as well as those with automatic transmissions around this era - featured a ~1.8" step (see image to the right) or a shallow recess instead of a ~1.8" centering bore as found on later AMC V8 engines. This distinction is important to make if adapting to a transmission where the pilot bushing is positioned further rearward due to a shorter input shaft length. All early and late cranks (in our documentation) feature a pilot bushing bore (the deeper bore in the crank) that is just over 1" in diameter whether they have the above step-bore, or not. On the later engines you are placing the pilot bushing where an automatic transmission would normally index the torque converter. Also be aware that on AMC engines originally equipped with a TH400 automatic transmission there may be a thin centering ring that will need to be removed to install the larger pilot bushing. If the bore measure ~1.7” instead of the expected ~1.8” you’ve got the bushing that needs to be removed. That ring 5352374 is located here.

Related Products

As required, we have complete transmissions or adapters available.

Installation Requirements

A proper driver is recommended for installation. However, Jeep owners are known for their ingenuity, we’re sure you’ll sort it out. If not, we keep these on the shelf if it takes a 2nd try.

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