The TCC solenoid is engaging. The scanner said the TCC solenoid was locked and that the current gear was 4th (which is overdrive I believe). I think the rpms are just too high, the scanner said 2530 rpm @65mph. I'm wondering if the TCC slippage of 255rpm is a problem??? Seems like it would be.

That would be the normal slippage under accelleration in any gear. When the TCC locks up at 48, you should IDEALLY see about 8-10 rpm'* of slip. So if it'* engaging, and you have that much slip, the next thing I'll have to ask is whether or not it seems to be low on power when accellerating in other gears? If your TC is that bad, it should affect you all the time.

Put the car in 2nd gear and get out for a cruise. Set the cruise control at 40mph. How much TC slip are you getting? Now accellerate. What does it go up to? Deccellerate, and what does it do?

I'm trying to figure out if it'* actually the TC or some other problem.

Right, when your TCC is "ON" then there should be very small slip, way below 255 rpm. TCC Duty at 0% means that the PCM is telling the TCC to lock up. 100% means no TCC at all.

I took the car for another spin. The TCC Slippage is 255 whenever I accelerate in any gear...including just sitting stopped with the car in gear. The car doesn't seem sluggish to me, but I'm not used to driving this kind of car.

I took it out and set the cruise to 40 and put it in second gear...the slippage was anywhere from 40-75rpm. When I accelerated it whet up to 255. When I decelerated, it when into the negative range, around -150.

I also tried the car in 3rd gear @50mph. When in 3rd, the TCC Slippage was between 2-10rpm. Not changing anything else, I then switched to overdrive, and the slippage immediately when to 255.

Your problem is at constant cruising speed. So try this:

What is the slippage when you are driving a steady 60 or 65 mph?
What are the rpms at that speed?
What gear is indicated on the scan tool?

The slippage @65 in drive is 2-10rpm. The slippage @65 in overdrive is 255rpm. The rpm at that speed is 2530, as indicated by the scan tool. If I put the car in overdrive, the scan tool says 4th gear, in drive the scan tool says 3rd gear.

Well, my take on it is that it can't be the TC. It doesn't slip in other gears. I'm assuming your PCM is calling for TCC lockup, and thinks it is, but it isn't. At this point I'd suspect the TCC solonoid.

I'm not the greatest tranny expert here, but that'* my take on it.

That'* really strange, why would the TCC lockup in drive but not overdrive? I'm stumped here.

Me too, unless the VSS input isn't telling it to?

The TCC is locking up in overdrive. It just seems to slip in overdrive, but not the other gears.