I have a 97 Mountaineer with a 5.0 (302cu) and a full time transfer case. 2 years ago it started to get a loud howling sound. Come to find out the oil in the case had not been changed in over 100,000 miles. So the transfer case locked into 4wd. I changed the oil and that got it to come out of 4wd. Now I have this howling sound all the time.
My question is, is there a transfer case that I can swap out for this one? I don't want the same model of transfer case. I would like one that is not a full time 4wd. Is there one out there? The Mountaineer has 268,000 miles on it and the 5.0 has never had a oil leak. This the only problem I have had with the vehicle. I change the oil every 5,000 miles and now the transfer case oil once a year because of what happen.

Thanks