Okay, Tequila Man. Care to guess on how much time it has left? That'll probably make the decision on whether I make the down payment on a used one today, or wait a few months for you to be ready.

I've been getting this check engine code (again, P1870) for over a year now. It'* been very intermittent. Since Bill and I changed the crank sensor a few weeks back, the car'* been running beautifully. (You two would get along great.)

Now, starting Friday, I've noticed a periodic shudder when the car is cruising in third or fourth gear. You'll feel and hear a gentle vibration, like unbalanced tires, for a second or two. Other than that, it'* running great. No slips, no odd shifting, no CE lights as of late, no excessively dark or burnt fluid. It doesn't drive like a dying transmission.

Have a mechanic drive your car with the computer hooked up to it. You can monitor all of the information to determine how much slip there is and so on. He should be able to determine whether it'* your transmission or the TCC. I wouldn't leave it in the hands of a random mechanic with an $1800 quote without trying to narrow it down more by taking it for a test drive w/the computer hooked up. IIRC correctly, the computer will throw out a P1870 with a slip of about 50RPM. Mine was 200RPM when I got it in. My TCC replacement, bushings, seals, and a little bit more ran about $950.

Your problem seems to be exactly the same as mine was a few weeks ago, as a matter of fact, in every single way. When the light originally kicked, the car had shifted from 4th to 3rd while decelerating. Given your problem is between 3rd and 4th, sounds like a failure to lockup, same as mine. Inside my TCC, there was charcoal caked onto a couple of the gears, another one had bad grooves. But I'd only driven my car for another 45 miles after the light kicked on, not an entire year.