I’ve built automatic transmissions several times. My first was a PowerGlide, the easiest automatic ever, and I’ve also built TH350 and Th400, and a couple of 700r4’s. But I’ve never built an electronically controlled automatic transmission before, and that’s what is in the Suburban and in need of some help. I’m not sure what is going wrong with it, but I suspect the front pump and torque converter are both at fault and who knows what else. It slips, it bangs, it does it all, and you never know when.
Our specific trans in a 4L80e which is basically a Th400 with electronic controls and overdrive, along with a lockup torque converter. We found this old video on youtube showing how to work on one, so we figured we would share it with all of you as well.
Check it out and let us know if you think you could rebuild your 4L80e or not.