Chrysler Repair: 1996 Chrysler T&C LXI Van, high RPMs, warranty provisions, transmission controller

Question
When I drive my van over 50 mph after a short while the RPM's will go up to around 4000-4500. I can only go around 60 mph to keep the RPM's down. Someone told me that it could be the transmission regulator or monitor.We had the transmission rebuilt about 18 months ago. There is about 150K miles on my van.

Answer
Hi Dominic,
I can't tell whether your trans is downshifting by itself into 2nd gear, which is called going into "limp-in mode", or whether it is slipping in 4th gear. But in anycase the best thing to do is to find the paperwork on your rebuild job and see what the warranty provisions are. Perhaps you have some free or reduced cost service available under the warranty. If so, go back to the rebuilder and ask for service under the warranty.
If not, then I would go to a dealer or a non-franchise automatic transmission shop and get a readout of the fault codes that are stored in the memory of the transmission controller and which will say what malfunction is happening. Then as to what the reasons are, you need to know what the shop and the manual says they are. Once you get the specific fault code numbers, ask what they say is wrong, what they propose to do, and how much it will cost. Then wait on making a decision until you can write me back to tell me the numbers and what they said. Then I can go to the manual and see whether it agrees or not. The readout should cost less than $50 and its cost might be applied to the repair bill if you give them the go ahead to do it. Using this fault code feature is the most economical way to get the proper repair.
Roland