Do parking sprags go bad?

Truck's been doing weird crap lately.  If I park on an incline, maybe half the time I'll get to experience it rolling forward or back with a CHUNK-CHUNK-CHUNK-CHUNK sound.   I don't really think that the sprag is going bad, because periodically I will have to hold the brake and shift to neutral in order to start it as the switch doesn't recognize park being a good place to start.

What I can think of is, in order of oh-E36 M3/Pain In The Ass:

• Parking sprag going kaput.
• Parking lever getting bent
  • Inside the cab being the worse case
• Cable stretching
• Cable adjustment.

Anything I've missed with those?  1993 F150, E4OD trans.

I had one go bad in a 4L60E in a 95 Caprice.  Put it in park and CLICK-CLICK-CLICK-PARK. Eventually, whatever was broken got loose in the case and it ate itself to death. 

Start with a cable. They aren't the most robust piece Ford could have put in...

IIRC Ford had issues with some trucks rolling away because they didn't fully engage "PARK" every time.  You may be able to find a service bulletin on that.

The parking pawl not engaging properly combined with the no start in park suggests there is a shifter problem.  First place I would look is at the base of the steering column, where the lever that the cable attaches mounts.   There are two screws that hold the lever to the shifter tube that like to loosen up over time.

Streetwiseguy said:

The parking pawl not engaging properly combined with the no start in park suggests there is a shifter problem.  First place I would look is at the base of the steering column, where the lever that the cable attaches mounts.   There are two screws that hold the lever to the shifter tube that like to loosen up over time.

This.  And, if it's not fixed it will eventually break something expensive internally from the rolling while partially engaged.

I'm pretty sure that's how I got my broken f350. The trans case was cracked from what I can only surmise was shifting into park at speed. When I swapped it to manual and pulled the shifter cables pretty much everything was loose. The cable retainer at the transmission side, the screw holding it to the truck up at the shifter side even the shifter linkage assembly down the column was loose and rattling around. Crazy.

Danny Shields (Forum Supporter) said:

IIRC Ford had issues with some trucks rolling away because they didn't fully engage "PARK" every time.  You may be able to find a service bulletin on that.

My 2000 F-350 started doing that ^^^ a while ago. I drive very little have so many projects it's waaay down on the list but I really should take a few minutes to investigate.

It most likely needs the shifter rebuilt. We sell the bushings, shift tube, and plunger probably hundreds of times a year, lol. The fact that it won't start in park points to this too. Maybe a cable too.