I'm having some problems with the tranny and hope someone has some input, the truck is a 1994 f-350 4x4 idi and the trans is an e40d. When the truck is cold the trans shifts very hard in all gears, the problem is after it warms up it slips and does not want to start moving from a stop. Once it starts moving it will shift, just hard. The engine rpm's sometimes also jump up and down about 300 rpm when driving. The tach sender was bad and I replaced it with a new one, that fixed the tach but did nothing for the trans. I bought the truck about two years ago and the trans had just been replaced, and I've only put about 5,000 miles on it. I tested the fipl with a volt meter and it checked out good. Any other ideas?