I just changed my 89 F250 5.0 from an auto to the ZF 5 speed. Swap went very smooth, trucks drives and shifts just fine. I am very pleased except for one thing. First I will say that the Flywheel, clutch disc, pressure plate, flywheel bolts, pressure plate bolts, clutch master cylinder, pilot bearing and the throwout bearing are all brand new parts. I also, have a new Manual Tranny Starter. Here is what happens, when I first start the truck everything is normal. There are no strange noises and everything works just fine. But, once the truck reaches operating temperature a faint ticking noise starts to come from the bellhousing area. This ticking sounds just like the head of a bolt making slight contact with something as it spins past. The noise will completely go away with the slightest push of the clutch pedal. It takes so little effort to make the noise disappear that all I have to do is rest my foot on the clutch pedal and the ticking stops. I have pulled the starter to see if maybe the flywheel was hitting the cone, no idication of that, I have looked through the inspection hole in the tranny to see the throwout work, watched it while my dad pressed in the clutch and it works fine, it has to because the truck shifts just fine. So, in conclusion, the noise seems to be temperature dependent and it goes away with the slightest depression of the clutch. Do I have something wrong with my new throwout?

 

Did you find a solution to your problem? My truck just started doing the same thing today.