I have a 2008 3.0 RWD with 119K on it.

This morning I noticed if I'm at 70+ MPH & I go from coasting to any level of acceleration/ cruise control it will give me a hard stutter/ sound 1-2 seconds after acceleration that lasts half a second. It doesn't slow the truck down etc. but it's much more noticeable today. The truck gives no issues when shifting gears at any other speed & doesn't give this issue when I accelerate at 50 MPH or lower (I'm not sure if it does it while in the 60s) It does make a whining sound when the gas is pressed going between 45-50 MPH & doesn't happen before/after those speeds as well. Any clue what this could be? I just bought the truck 1K miles ago & it sat without being touched for two years. I did replace the air filter 500 miles ago.

 

Manual or automatic?

Assuming automatic, service transmission

 

Automatic. Mechanic checked it a month ago & let me know it didnt need a fluid change

 

Okay so I recorded myself/ it yesterday and I think it’s just the truck up shifting. It seems like when I coast it downshifts and then when I apply gas it drives for a few seconds then upshifts. I uploaded it here if you could take a look. https://streamable.com/rrcd0i