i was driving today and at 75 mph then when i am on the freeway exit ramp i let off the gas and hear a loud whine then at i guess maybe 50 i hear a clunk then it sounds normal again and have not heard it since WHAT THE HELL WAS ITohh its a 95 2 door 4.3 w auto 4x4

Did the clunk sound like it came from the front diff area? It could be a sign that your vacuum switch on the transfer case is failing.

My guess: Your front axle was engaged from a previous 4wd usage, or from a faulty vaccuum switch.. The clunk was it finally disengaging. Check vacuum actuator, actuator cable and vacuum switch on transfer case.

before that noise the last time i whent off roading was 2 days prior about 100 miles and then after that noise i whent off roading for 5 hours using 2 and 4 wheel drive and sometimes 4 lo it worked fine during that time i never heard the sound again oh well thanks for the help if i hear it again more then 3 times i ll have to investagte

it seems it happens only with ac on maybe i am wrong but once i slow down to 55 there is a whine and gets louder til it reaches 25 then it clunks oh and before this happend the damn eng with 2 k miles on it stalled at 70 mph for 2 seconds then it restarted on its own before i had a chance to change lanes to get to the side of the freeway