* Year of the TH700R4: While the bolt pattern is consistent across many years, internal components and even the external case can vary slightly. Later models may offer some performance improvements, but using a significantly later-model transmission might necessitate some adapter work or adjustments. Ideally, you want a TH700R4 from a similar-era GM vehicle.
* Vehicle Application: Even within the same year, TH700R4s might have minor variations depending on the vehicle they were originally installed in. A TH700R4 from a larger, heavier vehicle might be more robust, but it might require some adjustments to fit perfectly.
* Flexplate/Torque Converter: The flexplate (or flywheel if you're using an aftermarket setup) and torque converter must match your engine and transmission. Using the wrong one will prevent installation or could cause damage. Your existing flexplate is likely compatible with a similar-year TH700R4.
* Shifter Linkage: The shifter linkage may need adjustment or modification to work properly with a replacement TH700R4, even if it's from the same year.
In short, while *any* TH700R4 *could* potentially be made to fit, the easiest and most reliable swap is using a TH700R4 from a similar year and model GM vehicle, ideally a Caprice or a similar-sized/weight car. Trying to use a transmission from a vastly different vehicle could lead to unforeseen complications. If you're unsure, consulting a transmission specialist is recommended.
