97 Yukon -- Stuck in Park

Every now and then I can't get my rig out of park. If I wait or restart the rig it usually clears the problem up and goes into gear. It doesn't have to do with pressure due to hills or not putting the e-brake on. Any place I should start?

There's a parking pawl return spring that might be weak, and there's an actuator rod that might be stretched. Maybe some other things possible too. Do you have a shop that is transmission savvy that you deal with on a regular basis? You may want to have them take a look before it locks up permanently, which of course it will do at the most inconvenient possible place and time.

Thanks Ron!