My 2001 dodge ram 1500 has a knock when in 4 high and low sounds to be coming from the transfer case. The u joints are good. Any ideas?

 

How many miles do you have on your truck? If it is only doing it while in 4 wheel drive both high and low my first guess would be your chain is stretched and it is hitting the case. If it isn't the chain then something else might have come loose inside. And of course the next issue is that it might not even be from your transfer case. Noises travel on these rigs. Another thing is the mount for the transfer case could be broke allowing the case to hit the cross member, skid plate or underside of your truck.

 

The truck 180xxx. How could I tell if the chain is stretched?