I've got a 97 dodge ram 1500 and I'm starting to think something is going on with the trans. There's hard vibration when it's in 2nd gear about to switch to 3rd, when I let off the gas and can hear there's a popping type of noise that could be a misfire maybe? But the popping and creaking noise happens right after I put it in park and the truck will even sometimes roll forward just a bit 10 seconds or so after putting it park and hearing that creaking sound. I'm just wondering what it could be?

 

Sounds like a bad or multiple bad u joints to me, or possibly a diff going out…hard to say without physically hearing seeing it….

 

Would that make it only shake in low gear? That's the only time it does it, either letting off the gas completely or shifting to a higher gear stops it

 

It could, Check the driveshaft before you do anything.