Hello. '03 Dakota. 4.7, automatic, 4wd The truck makes a very loud "bam" metal on metal, noise after its put in gear and moves. Forward or reverse. Does it on take off, also during the 1-2 shift, does it going 55. I do know its not the motor. What I don't know is if its the rear differential or maybe the tranny? I dont know how to describe the sound it makes other than to say it sounds like someone hitting ..say...the side of a metal garbage can HARD with a big hammer. Just once. I feel it under the truck as well...just can't pinpoint it enough to know if I need a tranny shop or rear diff shop or what? Please humor me on the description of the sound it makes, but that's what it sounds like! Any ideas at all? Its been a really good truck with no problems at all. Thanks in advance.

 

U-Joint

 

That's a good possibility.

Get it up on a lift before you lose a drive shaft.

 

+1 on bad U-joint(s).

Just from judging by your name here if you live in Florida and do wind up needing new u-joints, Advance Drive Line in Ocoee does great work at very fair prices. I had them do all 3 of my u-joints a few years ago. To save a few bucks I R&R'd the driveshaft myself, took it over to the shop, left it with them and had it back in just a few days. They used good quality Spicer parts and did a good job balancing the driveshaft. They are a great bunch of guys and have been in the driveshaft business a very long time so they know their stuff. They have another location in Lakeland called Central Florida Driveshaft too.

Jimmy

 

Do you get vibrations at higher speeds now or before this Bam/clunk?

Crawl under and look have you done that yet?