It has about 80K miles on it, and has the VIN "R" 5.7 V8. There is a cat-converter heat-shield covering the trans data-plate, but I think it is a 4L60-E. There is a modulator-type can on the passenger side of the trans case and the case has "24202519" cast-in on the driver's side. Recently we have occasionally noticed a hard 1-2 shift after everything was all warmed up. Now, the P1870 was set and the SES light came on. I erased the code and it hasn't come on again, even after a couple of 40 mile highway drives today. I understand that P1870 indicates trans slippage and is probably caused by a valve spool riding in a worn housing. Most likely to occur when trans is hot and then the computer sets hydraulic pressure up to max in attempt to prevent continued slippage; hence the hard shift. Symptoms all pretty consistent with what I have going on. I pulled off the torque-converter dust-shield, the converter doesn't look at all discolored from over-heating. I am tempted to pull off the pan and inspect for abnormal debris, then change the filter and fluid (I think both are original). Unfortunately, we are scheduled to take this van from CA to PA (and back) in a couple of weeks (no towing); what are the odds that the trans will last OK? Will synthetic fluid help the situation? If I buy a new or rebuilt valve body can it be "reasonablly" replaced with the trans in the vehicle; should I consider doing that while I have the pan off?