Here's a good one.

[Jughead]

This happened to me about 2 weeks ago when we were plunged into a polar vortex.

It was about zero out and I went to start the raptor and move it up the driveway so I could blow the drive. I parked it on an incline of my driveway. Not very steep. I had it in 4WD and put it in Park. I took my foot off the brake and the truck starts drifting backward about 8 ft and then stops. WTF?

I repeated this several times thinking it was a fluke incident. Nope happened each time. I tried taking it out of 4wd and setting the parking brake.....no difference. Nothing changed and it happened each time.

Any ideas as to what happened here?

I had an excursion years ago that did something similar only it occassionally jumped out of park when parked on a hill.

 

[Taterdude]

I didn’t happen to slide on icy road did it?

 

[Jughead]

There was a half inch of snow but no ice

 

[Reaper308]

Did you try backing it up in the same spot and see if direction of truck made a difference? That way it would have ruled out the surface area? Just a thought.

 

[Ruger]

It seems to me that the Park pin in the transmission has become damaged. It's either that, or the linkage between the transmission and shift lever has a problem. As this is a safety issue, I think you should use the parking brake from now on until you can get your truck checked out.

 

[Jughead]

Did you try backing it up in the same spot and see if direction of truck made a difference? That way it would have ruled out the surface area? Just a thought.

Yeah, tried that. Moved up a few feet and back a few feet. Same.

 

[thatJeepguy]

Yeah, tried that. Moved up a few feet and back a few feet. Same.

I agree with @Rugar. Sounds like a issue with the pawl mech or spring. Fix immediately.

 

[Reaper308]

Yeah, tried that. Moved up a few feet and back a few feet. Same.

Yeah that definitely sounds like transmission issues! That needs attention ASAP! Good luck keep us posted please.

 

[Jughead]

Took it in to the dealer for a previous CEL (electrical fault with waste gate actuator} We'll see what he finds.

Still under warranty.