Hello. I have a 4.7L 2004 Dodge Durango. It has been a good vehicle other than the noisy lifters that have plagued it since we bought it.
Yesterday it started doing something new. A knocking sound from under the vehicle during acceleration. It feels like it is right under the floorboards.
I can get it to stop doing it by switching from AWD to 4-Lock.
I did do all four brake pads last week but don't know if it is related.
Any insight is appreciated. Thanks.
Tom

 

Rear exhaust stud is likely broken.

Get better oil and that 'slap' at startup will diminish.

IndyD