FINALLY FOUND THE PROBLEM

1. Probably my fault - it was stuck in 4WD Low. The mechanics at Loudon's was able to bypass the computer and force it out of 4WD Low. Drove it home - no OverDrive light flashing However...

2. 4WD switch on the console inside came up as having a problem. So that switch needs replaced. $84 for a freaking switch, and I told him might as well bypass it and just wire it to be in Automatic all the time when it comes down to it. This can cause the High and Low lights to flash.

3. Shifting motor should be replaced. This is about $300. I think this is a good thing to get done.

4. RIGHT FRONT SPEED SENSOR STILL COMES UP AS A PROBLEM. You know, this one is on the wheel well with a long wire going to it? IT'S NOT ON THE TRANSMISSION. Though I think $415 for this is excessive, the guy who spoke to me says an after market sensor 'could' cause a different reading between that and the Left Front Sensor. This affects the 4WF Low and High lights to flash, and can affect ABS, since he said they got that to light up.

I may end up liking this vehicle now that it's about to run right and it's not sucking down gas.