My truck started doing this today while driving home in heavy traffic.

https://photos.app.goo.gl/2BhQgF7Y7wmNABic7

It only did it at really low speeds when I was coasting to a stop. The sound / vibration comes at the end of this video (which is 19 seconds long).

Thoughts?

 

How many miles on the truck? Is there plenty of trans fluid?

 

4WD more likely than the transmission. Check with some of the 4WD owners.

 

If you're referring to the chugging and shaking, that doesn't sound like a transmission problem. Trans problems are typically slippage (when the engine suddenly revs up like it's been shifted into nuetral) or sudden/clunky/random shifts. Pull the dipstick and smell it - fresh tranny fluid has a bitter sweet smell - burnt tranny fluid will be one of the worst things you've ever smelled and you'll know it. If you've ever smelled burnt tranny fluid, you'll never forget that smell. Fresh fluid still stinks, but it's a totally different animal. Also, burnt fluid will be black, fresh will be red.

This seems like an ignition (bad plugs/coils?) or an air/fuel delivery issue (intake leak? clogged injectors?). Maybe even a very clogged air filter or a dirty MAF sensor (only use MAF cleaner, NOT brake cleaner). Also, check your air filter housing for leaks. I chased a similar chugging problem in an old suburban and finally found that the crappy K&N intake boot wasn't fully seated on the throttle body, which let in a bunch of air downstream of the MAF and the computer was trying to compensate for this. Once I seated the intake correctly it ran like a dream.

Does it only chug and shake at idle? Does it go away when you get on the throttle?