Hi Guys, I bet you thought I fell off the planet. Sorry for the delay but with being ill and other family urgencies, I finally got around to dealing with the truck. And then it took two weeks to get up the courage to write this. So here it is. I’m an idiot.
After finding a used diff for $150 like the tranny guy told me to do, I put it all together and what do you know, same problem! AHHHHH! Rolled the truck up and back, locking up, and took notice of the front wheel. It looked like it was the front locking up now. So I jacked it up and sure enough, it was the front! One of the caliper bolts had fallen out, the bottom one, so when the wheel turned in reverse, the caliper could rotate and jammed the wheel.
My own fixation on the rear was misguided as I associated the “reverse” problem with something in the drive train. But I guess what really threw me off completely was the tranny guy when he had it up on the lift. He said he could feel it catching in the diff. Well, the bolt was $1.50 from Toyota and I got two cuz I figured that other one had gone through a lot of stress with the wheel lock-ups.
Well, I have a spare diff now; in 15 years when I need one, I won’t be able to find one so I’ll just keep it in the shed.
Thanks guys for all your help earlier. I guess I learned to check all the wheels regardless of where I think the problem is coming from.