Hard Shift 1-2 and TC Locking problems

My 96 Xploder has nearly 150k on it and just today started acting a bit funny. It is overdue for a tranny fluid change (going to be done by the dealer on monday). The symptoms are that sometimes it shifts hard from first to second and back from second to first (on the downshift). The other problem is that is will no longer lock the torque converter in third or fourth gear. The OD light did flash briefly today but quickly went out. It does go into OD fine but wont lock the TC anymore.

Is there a solenoid that directs the TC to lock?

I have read that a new Valve Body is sometimes recommended. Any ideas on a good place to get one? How about other upgrades?

I will start by dropping the pan on Saturday, replacing the filter, and looking for debris. Anything else I should replace while I have the pan off? Once I have done this, I will take it to Ford and have the tranny flushed and fluid replace. Anything else I should do?

BTW, this Xploder is a 4WD with the 4.0l V6.

Thanks in advance,
Aaron

A flashing OD light means a code has been stored in the Computer. Now, I'm sure a service wouldn't hurt but, the best thing to do is to have the code retrieved from the computer. The code would tell you the best route to go next, as far as diagnostics go.

There is a solenoid for the TCC(Torque Converter Clutch)

A GOOD, valve body is only available from dealer. Take your chances with anything else you find. As far as these valve bodies are concerned.

It shifts hard because its in fail-safe, limp-mode, safe-mode whatever you would like to call it...

Will any code reader give the information I need or do I have to have the dealer pull the code? My dad has a reader for mid 90s that I think will work. Once I have the code, the dealer should be able to tell me what it means correct?

Thanks again,
Aaron

you have lost a band in your tranny most likely. that is causing the hard shifts. Expect $1500-2000

A code reader for OBD II should pull the code. Post your code. I can give you a description and maybe point you in the right direction.

Also, If a band broke you would have lost either Reverse, 2nd or 4th gear. Everthing else would work. Well, as long as everything else was in good shape. There is a band for 2nd gear and band for 4th. And another band for reverse.

4R55E

Just trying to keep the info straight :)

Thanks for the clarification. I didn't think there was a band broken as it drives pretty much normal. The only difference is that the shift from first to second is more solid than normal. I spoke to Ford and they state the lack of the TC locking and the more solid shift is the behavior of "safe mode" operation. They felt the problem was most likely a sensor failure. My dad does have and OBD2 code reader so I'll get the code tonight or tomorrow morning. Once I have that, I should be able to figure out which sensor failed and get it, the filter, gasket, and anything else I need. I will then replace the sensor and filter and schedule a flush early next week. Any idea how many sensors this bugger has?

Ford was also unsure which tranny this has in it. Supposedly they need the VIN to determine which one it has.

Sensor failure or the TCC isn't working. Thats a givin. Post the code. Don't waste hard earned money on a flush or service. Get it diagnosed right the first time. If possible.

Will do. As soon as I get the code reader, I'll post the results.

Thanks,
Aaron

Well the code reader couldn't pick up any codes. Looks like the code was a custom Ford code not a generic OBDII code. I issued a reset on the codes and it now drives totally normal. I talked with Ford and they felt the problem was dirty fluid causing a shift / lock up problem. I dropped the pan and replaced the filter yesterday. The fluid definitely needed to be changed but there was no debris in the pan and I don't thing the filter was ever changed. It drives totally normal now and I am going to have the system flushed totally (throwing away the 4.5 qts I just added) this week. If it generates another code I'll try to read it again but if no codes are displayed, I'll have Ford read it.