I have a 95 F-150 w/ 351 supercharged and an E4OD. The tranny also has a shift kit for faster shifting. A few weeks ago the tranny began to shift really rough. It shifted hard through acceleration through 1-2-D, then would shift at a lower engine speed than normal into OD. Even shifting fron neutral/park into gear would result in a jolt and a clank. I took it to a shop and they checked codes and got nothing. They checked the Throttle Position Sensor, but didnt have enough time to check Neutral Safety Switch or any other sensors (I had a flight to catch). The TPS was working fine. They changed the fluid, not finding any metal shards or anything catastraphic. They also commented that the fluid seemed clean and that it had been replaced recently (I bought the truck about 6 months before this happened). I took it in stride and went on my way. The shifting was fixed! It seems the fluid changed has restored it back to good operating condition, but I was just wondering if this is a sign of worse to come, or just maybe there was genuinely bad fluid or it needed changing. I am considering having all the sensors checked out as the NSS was the fix for a 91 F150 w/ E4OD that had the exact same symptoms. Any thoughts?

 

i would install an aftermarket cooler and remote filter with a spot for a temp sender to monitor whats going on. your VSS may also need removed and cleaned along with the rear diff fluid replaced.