I posted a while ago that I was replacing the torque converter in my f350 with the 7.3 IDIT and an E4OD due to a shudder problem so i replaced the converter with a stock replacement unit and it solved the problem but 2 times since i replaced the converter when it was coasting and the torque converter was unlocked and I went to accelerate it was like it was in neutral and then it would just go back to normal like nothing was wrong. However the second time from that point on it shifted funny like it had gone into limp mode until I stopped and shut the engine down to check the fluid and check for codes which there were none. When I got back on the road the trans acted like nothing was ever wrong and I was hauling 5800lbs at that time. When I did the converter I also replaced the filter, gasket, front and rear seal, cooler and all rubber lines also I flushed the steel lines and the cooler in the radiator even though the pan,filter and magnet were all clean. I also checked the fuel lever position sensor or tps to make sure even though it was fairly new and I suspect the solenoid pack or some kind of electrical issue but I didnt want to lay down $250.00 for a shift solenoid if the tranny is toast. I wish I had done the ZF5 swap when I had the chance. Anyway sorry to be so long winded but I sure could use some advice on this one. Thanks!

 

Broken transmissions don't fix themselves they stay broken so it's not possible for you to have a bad trans one minute and a perfectly good trans after stopping and restarting again. This transmission is 100% computer controlled and shift related issues are often traced back to something electrical or electronic, so keep pulling codes until you get something.. anything, all codes are trans related in this case. BTW.. you should at least get an all clear code 11 or 111 when you do this, if you got no response whatsoever you didn't even get into the PCM.

 

I couldnt agree more, mechanical things dont usually act up intermittently but electrical things do and I am certain it is some sort of electrical problem but I dont have alot of money to fix it by the process of elimination and cant find any sort of diagnostic guide, heck if I just had the theory and operation of the electronic control system I could diagnose it off of that but anything I have found is really vague or just says to take it to a shop which does me no good and all a shop will do is rebuild the trans they dont check anything else as I found out when the e4od went out in my brothers 90 f250 aamco rebuilt his trans 4 times under warranty because of a bad throttle position sensor. Also I do get the 111 all clear code, does the tcm store codes or are they gone once the ignition is turned off? Thanks

 

Conanski has it right, these transmissions seem to suffer from electrical issues often. Not that we are telling you to start replacing parts, it could be as simple as dirty or loose connections.

 

The TCM will keep codes for about a month after the last time the OD light was flashing.

In this vintage truck the false neutral is not uncommon. It is VERY hard to diagnose, but I'll share what I learned over several decades of working with these. It is almost always a failing TRS (Transmission Range Sensor, also called the MLPS - Manual Lever Position Sensor, or NSS - Neutral Safety Switch.) This is the sensor on the driver's side of the transmission where the shift cable attaches. It is REALLY easy to change, and a new one is about $50. If yours is more than a couple years old I recommend changing it.

 

I think we may be on to something here and I wonder if I did something to the MLPS accidently when I removed the transmission to replace the torque converter and that would probably not throw a code being as the problem is so intermittent anyway. The TRS is the original anyway with 211,000 miles on it so replacing it wont hurt and it may give me my old truck back! Not that the new to me truck with the n/a 6.9 is bad but the turbo 7.3 is so much more powerful. If anybody thinks of something else let me know, i am going to try the TRS and see what happens. Thanks!

 

I had a blow out on the passenger side and it ripped thru the fender well and broke my plugs to the wiring on a 93 f350 7.3 none turbo I bought a new plug assembly and my tach is not working and the Trans is in the limp home mode any surgetions...?...

 

@wayne048 - Welcome to FTE.

You'll find a bunch of really helpful people here that are always happy to help. You'll find that you're more likely to get help if you start a new thread specific to your problem instead of adding a reply to an unrelated subject.

 

I'm new to this site and how do I post a new post please

 

Thank YOU for clearing that up. Some of this stuff is like alphabet soup!

 

At the top left of the main page of this section (or any section) of the forum there is a blue button that says "new thread". Click on that