4L80 out of a 93 suburban
The '93 is a less desireable year, there have been many upgrades since then, many can be used in the '93 if you have it built.
I bought a 1992 454 dually without a transmission, the shop that had it said the trans wasn't rebuildable. I got a 1998 4L80E with 60k on it and it's been working good for 7 years now.


