99 dodge ram 1500 4x4, will not shift out of park on incline. If I shove the truck up a little and block the tire I can shift the lever under the truck through all of the gears.

 

It's not at all uncommon for the parking rod to periodically get stuck when the vehicle is on an steep incline. By doing what you did, you should be able to put the truck in drive and move on. When on a steep incline, it's best to set the parking brake, then put the truck in park on an incline or chock the front wheels towards a curb, if available.

 

All automatics.

 

Every once in a while somebody goes to say (IRL) that "you don't need parking brake with the automatic transmission, it has park". Well, this is where you'll need the parking brake.

 

Yep, they will do that. There is a pin in the shifter that catches on a sprag in the transmission. It gets in a bind when the vehicle weight is against it. That's why you set the parking, or emergency brake to park. I even do it on my 2016 Mazda.