I previously posted engine cooling issues arising after replacing car battery. Turns out water pump coincidentally went bad at same time. I also had the "Transmission Fault" come on and then disappear. Now the message reappeared/disappeared but the Check Engine warning came on and ODB Codes P0734-P0745-P1233 appear. These translate to Gear 4 Incorrect Ratio/Pressure Control Solenoid A/Fuel System Disabled or Off LIne. Transmission fluid ok, but I have no idea when it was last changed. Transmission pan leaks and looks like it should be replaced. I know the 2002 S-Type trans is the Ford trans used in several Ford models and has reliability issues. Before I have transmission service done any words of advice on what issues may lie ahead

 

Well you have the less desirable Ford 5 speed transmission. You did not post how many miles on the car/transmission. As the miles build on these transmissions they suffer from bore wear. What Ford did to save money is run steel transmission valves in an Aluminum case. As you might guess the Aluminum wears first. This then allows fluid to leak past the transmission valves causing shifting issues due to improper fluid flow. These transmissions are adaptive so at first they can adjust to the declining fluid flow but eventually reaches the adaptive limits and starts throwing codes and driving funny.

Now they have a nice in-car repair kit to sleeve those bores and restore the proper fluid clearances. Before that it required the transmission to be removed and repaired on the bench.

So depending on what you can find either rebuild your transmission doing the mods and be aware that there are other mods that need to be done too! Or buy a re-manufactured transmission with all the updates already done. If you look at places be sure they mention bore wear and they have re-sleeved the bores. You also most likely should replace all the shift solenoids and possibly the valve body. The good thing is it's a FORD. So ton's of mods and places to get this transmission worked on. These were installed in millions of Fords and have been modified to hold 1000+HP as they made their way into the Mustangs so a huge after market developed.

I had a 2003 Lincoln LS V-8 sport with the same transmission. We messed around under warranty a bit with solenoid replacements before Lincoln warranty would allow the mechanic to install a complete valve body.

So I think your right to replace the leaking pan and put new fluid in as that's WAY cheaper than the next steps! It's possible that this will clear your errors but that incorrect gear ratio codes is NOT a good one!
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