Clunk from P to R but not D. WTF?

[CVC22348(b)(1)]

Hope someone can enlighten me...

I left my car garaged for about a week when I went out of town. Got in yesterday and wanted to take a drive since all I'd been riding in was little taxis in old Mexico.

Started up the beast and shifted to reverse...clunk! "WTF?"
I put it back in park and shifted down to drive but no clunk. Shifted up to Park and back to reverse...CLUNK!

I started to panic...while sitting, idling, and calming myself down I decided to go for a drive around the neighborhood to see if any other gears were clunky...nothing. Stopped and the P to R seemed to go away.

Hasn't happened since.

Thoughts?

[Aleks202]

Well i mase well try...

This might be way off the mark or might be exactly correct. SOOO...

The first question is, does the car sit on an angle in the garage or driveway, like an incline of any sort. If this is the case then all that is happening is your not engaing the handbrake(footbrake in this case) hard enough. The car then rolls and is stopped by the transmission itself (the whole point of a park gear). When you take it out of park, the noise you would hear as its going into reverse is the 'clunk' because you are relieving the pressure of the whole car from the park gear(the transimission, not the best thing to do). This would happen all day long if you put it in park(then all the cars weight is transferred back to the park break) and then u pull it out again...

Now i have a sneaking suspicion checking the photo you have up, that there is no incline and therefore that my idea is really just a theory. And all i can say is hope it doesn't happen again and its a good thing that it has stopped now.

[CVC22348(b)(1)]

Originally Posted by Aleks202

Well i mase well try...

This might be way off the mark or might be exactly correct. SOOO...

The first question is, does the car sit on an angle in the garage or driveway, like an incline of any sort. If this is the case then all that is happening is your not engaing the handbrake(footbrake in this case) hard enough. The car then rolls and is stopped by the transmission itself (the whole point of a park gear). When you take it out of park, the noise you would hear as its going into reverse is the 'clunk' because you are relieving the pressure of the whole car from the park gear(the transimission, not the best thing to do). This would happen all day long if you put it in park(then all the cars weight is transferred back to the park break) and then u pull it out again...

Now i have a sneaking suspicion checking the photo you have up, that there is no incline and therefore that my idea is really just a theory. And all i can say is hope it doesn't happen again and its a good thing that it has stopped now.

Right. No incline. And I always engage the park brake before putting it in park on a grade. My wife's Armada suffered the consequences of gear lock due to relying on P to keep it from rolling. After a couple of years of that bad habit, we had to change the transmission.

Thanks for the theory...

Another theory, by my neighbor, is that the tranny lost pressure at that point due to sitting so long...hmmm...maybe it was the hyperdrive motivator...

Well, it hasn't happened again. If it happens again next time I leave it garaged for several days I'll know it's due to innactivity. That just means I'll have to drive it more often!

[Aleks202]

Yeh sorry, it was a long shot with a slim chance. Didn't know how much you knew about the issue...
But i tell you what everytime i jump into someone else car to go somewhere and u hear the gearbox creaking and moaning beneath you, i can't help but cringe.

Ohh well goodluck, lets hope it doesn't happen again the best way you know how... Let Her RIPPPP