* Engine Size: The transmission must match the engine. A transmission from a Suburban with a larger engine (like a V8) won't work in a Silverado with a smaller engine (like a V6). You need to verify the engine size and transmission type are identical.
* Transfer Case: The transfer case (the part that handles 4x4 function) needs to be compatible. While often similar, slight differences could exist.
* Transmission Type: There were different automatic and manual transmissions used in those years. You must ensure the exact transmission type matches (e.g., 4L60E, 4L80E, etc.). This requires checking the transmission codes on both vehicles.
* Bolt Patterns and Mounting Points: Even if the transmissions are ostensibly the same type, subtle differences in mounting points could prevent a perfect fit.
In short: Don't assume compatibility. You absolutely *must* verify the exact transmission type (and ideally, get the part number) from both the donor Suburban and the recipient Silverado. A parts store or a mechanic specializing in these vehicles can help with this crucial identification. Simply knowing the year and model isn't enough to guarantee a successful swap.
