My son just blew the transmission in my 2002 Trailblazer 4.2 that I bought just 2 weeks ago. I have a 1999 Blazer Mp 4300 in my yard with a blown engine. Can I swap them out? Any help would be greatfully appreciated. Thanks. Alan. alanpatrick1267@gmail.com

 

Welcome to the forum. Wish I had better news for you. Short answer is no, different bell housing, torque converter, pump and input shaft. Could swap parts and pieces as long as the parts listed aren’t damaged on 2002 transmission. Be sure to flush cooler and lines when changing any transmission.
Good luck
Brad

 

As transman said, you will need a new Torque converter, Input shaft is different as a result, Bellhousing you need a T50+ Socket to swap, as far as the pump i dont recall them being different? but trust the expert on that too and swap it over, though the pump may be destroyed depending on what killed the tranny, will need a pump gasket and while in there inspect the stator/pump body and replace the rotor/vanes.

 

Thanks, @Mods Good tip on the T50+ bit, always forget to mention it's not a normal Torx bit. I wouldn't bet any money on this but the input shaft on the 4.2 will be the problem as it is ( if I remember LOL!) 283mm 27 spline and stator length is longer. 1999 would be the 298mm 30 splines.
Good luck @Alan Patrick

 

Thats odd, considering that both vehicles classify as Truck/SUV so i'd figure GM would give them the same, Though GM doesnt tend to make sense with all of their decisions lol.