TC Lockup issues
I am working on a 03 7.3 crew cab F250. When the converter is locking up at the end of 3rd gear and 4th gear the truck shutters. The engine RPM's bounce around as the truck is shuttering. The truck has about 90k miles on it and the transmission fluid and filter have been changed - just dropping the pan, not actually flushing the converter out. I believe they used Mercon/Dexron III fluid when they did it.
I recently purchased AE software, hooking it up on this truck and doing a few drive cycles I can see the converter lockup numbers (I think it was called TC Modulation) bouncing around as the truck is shuddering (0 unlocked and range up to around 32xx when it finally locked up). It looks like the system is trying to "slip" the converter into lockup instead of just directly locking it. Is this normal? I was hoping I could actuate the converter lockup with AE but it does not have the option to actuate anything on the 7.3 - I know my 6.0 could actuate quite a few things but I didnt pay attention to see if TC lockup was one of the things I could actuate.
The owner of the truck took in into a dealership and they told him the converter was going out and their fix was to put a $4500 transmission in it. When it was in the dealer I dont even think they drove the truck and they only had it for about an hour so I dont think they did much more than plug their scanner into it and see what it had to say.
I would hate to put a converter in the truck and the new converter act the same way the current converter acts and it seems kinda wasteful to put in a new transmission when it only looks like the converter lockup process is the only thing having trouble.
Thanks for any help or advice.