Chrysler Repair: Transmission Codes: 0734/0736/0740, torque converter, home with the kids

Question
2002 Chrysler T&C Lxi FWD 3.8 with 138,900 miles - Vehicle has been well maintained - Van lurches forward when placing in gear - When placed in Reverse, there is no movement and only a "whining" noise is heard - There are no audible "clunking" or "grinding" noises - The transmission was performing great until my wife barely made it home with the kids last night - It has the following error codes from an OBDII Reader that I just pulled today - PO700 / PO734 / PO736 / PO740 / and PO846 - Any assistance is greatly appreciated - Thanks...

Answer
Hi Gregg,
I don't find there to be an 0846 code, might that be a typo?
The other three codes are about the transmission. The 0740 says that the torque converter lockup control is out of range (that is the feature related to preventing torque converter slip when going above 40 mph). Unfortunately, that code is usually the result of a problem with the torque converter itself or the oil pump bushing. The 0734 and 0736 say that there is slippage in reverse gear and 4th gear. You have observed reverse already. There are a number of possible causes for the reverse issue, some of which might not be related to the internal transmission (which otherwise requires removal) but unfortunately the gear ratio error in 4th gear (unless by chance that 0740 was the pure cause) points to an internal transmission issue.
I assume that you did check the transmission fluid level, but if not do so. If that proves OK, then based upon the codes I believe it would be prudent to try to find the best Chrysler tramsmission repair shop near you. They might do some diagnositics that would point to something related to the valve body or solenoid/pressure switch assembly either of which could be repaired without removing and disassembling the transmission. Barring that, it would point to having to remove the transmission and relace damaged internal parts.
I wish I could give you a better prognosis.
Roland