i have an 01' F250 4R100 that on occasion when i put it in drive, i need to get the RPM's for it to engage. It only seems to do it after i have backed down or up a slight hill. I have been on level ground each time i put it back in D to move forward. It did it once last week after i backed my boat into the water on the ramp. It was time for a service so i did that as prescribed in the sticky with 20 qt of new fluid and a new filter. Well it just did it again after i backed up a long , slightly inclined driveway. I did put a john woods valve body in it 60K miles ago and at the time snapped one of the 10mm studs that is located in the corner of the valve body right next to another bolt. I didn't want to ruin anything so i just left it alone. made the mistake of use the ft/lb torque wrench and not the in/lb one...duh...live and learn. It has been working great for 60k miles which is why i left it alone. Ive owned my 6000lb boat all over the place, loads of stone and tile hundreds of miles over hills all with no problems ever. I have a 27 row 6.o cooler in it and my fluid has never gotten over 150 degrees. My pan was clean with no metal in it when i changed the filter with the normal small amount of "fuzz" on it. And hardly any. Any ideas what i should look at as fas as an easy fix or test to determine if its a solenoid or something. I hooked it up to a snap on scanner and there are no codes for it. It drives and shifts great while driving now. I tried to get it to duplicate the slip but i couldn't make it do it. Any ideas Mark??? hoping i don't need a new tranny.....cant afford that right now.