1500 should have an NV 231D. There is a round plate on the back side of the case that should have that information.

 

231d it should be. Mine has a Mopar one in it. Most ive seen have New Process 231d badges on them.

 

do they make the transfer case saver bushing for the 231 all I can find Is the saver for the 241 and where could I get the snap ring?

 

What was the differnce from 97 T case to the 99. I know the speed O was in the tail shaff of the 97

 

Shift pattern, and VSS are the only difference I am aware of.

They do make the t-case saver for the 231.

 

thanks guy for the help I hope that it works Im tired of that noise when im on the highway

 

VSS ? Mine is leaking and I can get a 97 T case from a friend of mine for 100 in good shape if it would work in my 99. Could you change the tail shaff on the 97 and install the 99 tail shaff ? I also know he don't have the shifter on would the one in my truck work

 

the other thing I should have put in there is when it is making the noise if I shift out of overdrive and the RMPs go up the noise definetly doesn't go away but it quiets down a whole lot.

 

The difference is like HeyYou stated. The VSS and shift pattern.. Not 100% sure on swapping the tail shafts. I went through like 5 tcases with the same noice you describe. Eventually they just split in half and spilled their guts out on the highway. If you replace the transfer case and still encounter issues your next step is the transmission.. Thats what mine ended up being. Guy that bought the truck had the same issue with his and there was an internal issue in the trans. Cant remember exactly what he said it was though..

 

well I do know when I changed the trans filter the last time there were 3 pieces in the oil pan of what looked to be a ring they were about an 1/8th inch thick and I was told they were from a band inside the transmission could that be it cause I don't even know exactly what the pieces came from