Jmag034

ill see if i can get a video of it....

Jmag034

well, my camera is broken, so ill just try and explain for in detail

ill be on the expressway crusing at lets say 55-70 mph...i will be keeping the gas constant, and for no reason, the RPM's will jump up to like 3k or more...it feels like it shifts into 3rd gear, then after about 5 seconds at 3k, it down **** back into overdrive and ill cruse again around 1800rpm...sometimes it will happen 5 times in 20 miles on the expressway, other times it wont happen at all...

but for sure when im in OD going between 40 and 43, and i encounter any slight incline, the RPM's will stay at 1000, and the car will just shudder really bad, even if i give it about half throttle it wont shift into 3rd, i've gotta give it some serious gas for it to downshift into 3rd so i can accelerate...

89GT5.0

my car is doing the exact same thing...did you ever find out what was wrong?

Jmag034

no, gonna look into the converter

deadcarnahans

The downshifting is caused by a defective selector position sensor. Easy to replace but you will have to lower the tranny down a bit to get to it.

The shudder is from the lock up converter, but this is not the cause, so a different converter will do the same thing. You need to upgrade the valve body and change to Merc V fluid.

ford4ever9800

Was lube guard what you put in the trans? Its the stuff ford has in them from the factory, and if u had it flushed at the dealership they should have put it in, it fixed the tc shudder on my van.