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Suburban Computer Problem?

Above is what happens when I type a message when I am being bugged to hury up and go to the mall. And I don't even proof read what I typed.

This should read a little better:

I have a question about a transmission problem. However the problem MAY be rooted in an earlier power short I had.

I will start with the actual trans problem. I put my 2004 Suburban into a local trans shop with a very good reputation. The truck developed a problem and was stuck in gear. I was able to read the codes and it showed trans Sol A "electrical" and Sol B "electrical". The trans shop changed the two but that did not fix anything. They then changed trans. They called me that truck was running fine BUT that on the Computer they were getting odd indications. When driving and monitoring with computer plug in the truck changed gears fine. However one field on the computer showed the trans stepping to second, then third, then Park/Neutral. Yet the trans was correctly in 4th gear. But the computer still gets a signal not that truck is in 4th but is in park. They changed neutral switch but that did not fix anything. In test driving the truck with replaced trans I seem to think it is driving OK except that I feel it is very slow in shifting into second gear (around 4-5K rpm). And their computer still read I am in park when I am really in 4th. I THINK he said as truck down shifts it then reads in 4th when actualy in 3rd, and reads in 3rd when in second.

Now some history. I have after market equipment in the back of the truck. I have an 8 Gage wire going from the battery thru firewall under floor mat along wire harness to the back (no fuse). The wire got pinched to ground as I was driving last year and suddenly EVERYTHING went crazy in truck, wipers came on, door locks went crazy, speedometer pined, oil pressure pinned, truck stalled and I coasted to shoulder. The couple minuet short totally drain battery and melted the insulation on 8 Gage wire.

At the points that the hot wire touched the wire harness it melted the insulation on those wires and I assume gave everything 12 volts as it quickly drained down the battery.

I was able to remove the shorted cable from the battery and jump the battery and drive home. I checked the wiring harness and it looked like the damage was limited to an area next to driver seat. Mostly were a bunch of wires branch off the main harness and go under drivers seat. I separated the half dozen melted wires and coated them each with liquid plastic tape or insulation. And for the most part the truck has been good. But every now and then odd things happen. I will shift into drive and electric locks will go crazy for a few second, then never a problem again. Or I will put truck into park and the speed will show that I am going 60 mph, then if I drive at 30 it will read 90 on speed speedometer. Removed battery cable overnight fixed this. Sometimes oil pressure will be pinned high.

I have checked several times and I can not find any bare spots or shorts on factory wiring. Now with this trans issue I am thinking it to be the result of the short?

One hint, two of the wires that melted / shorted are yellow and white and had been twisted the entire run. I had to undo the twist for a couple of inches to re insulate. As a ham I know twisting of wires is done to eliminate coupling of data from one wire to another. Maybe I am picking up "noise" in a data line?

Anyone have any pointers what I should be looking at?
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