It seems this problem has gone around after reading it on a lot of different boards. The IWE

(passanger side on the fire wall) switch that controls the vacume for the hubs goes out

(gets wet) causing this god awful noise up front. It allows the hubs to try and engage

while you are in two wheel drive. I have replaced it and seem to have around 17pounds of

vacume while not driving and goes down to about 13 when on the throttle. Before I

replaced this switch it was at 10 and down to zero on the throttle causing the grinding

noise between my hubs and the gear that engages four wheel drive. Problem now is I still

get the noise(not near as bad but its still there) and before I spend 1k on replacing my

hubs I want the noise to stop. Does anyone know what amount of vacume should be on

the hub while in 2 wheel drive and how far is should drop when on the throttle? Please help!!