I was wondering if anyone noticed that if you rev your truck, just to like 1000 rpm's, while in park and let off, your EGTs go down faster than just letting it idle by itself.

egt's will take longer to go down in that scenario because you are adding more fuel than boost.

No doubt, that's like saying EGTs go down slower if you idle your truck in the driveway for 30 minutes instead of driving on the freeway for 30 minutes.:confused:

Just what I have seen on my guage maybe an edge glitch then.

When you let off, the fueling drops to next to nothing passing primarily air across the probe cooling it down. Just like coasting down a hill...