1991 Isuzu V6 Four Wheel Drive Automatic 198400 miles
I just got a '91 Trooper, 2.6 ltr. As soon as I drove it away (after paying, of course!) It started this noise from underneath that I can only describe as a " growling" noise--I can feel the 4WD stick vibrating. It does it intermittingly at first, then increases in duration and decreases the timespan between " growling" sessions as it warms up. It also seems to lose power as the noise continues. It shifts fine, doesn't slip or grind. I was told it might be something in the transfer case. What about the hubs--they are automatic locking.I don't know anything about them (have never had a 4WD before!).
When I got home and read the manual, I found it had been in 4H, for 35 miles at speeds up to 55 mph! In addition, the seller overfilled the transmission fluid--said it would be alright! I drained the transmission fluid and put in a new filter; the fluid was red, and no metal fragments in the pan. Also, the " POWER" & " WINTER" drive buttons don't work either. What parts can I check, and how can I make sure they are running properly? (I tried to leave you a donation, but my mother is in the hospital and this is her computer--she has the PayPal account! I'll send one later. Thanks!)