92 xe v6 4x4 5spd. let me see if i understand this right , based on what i've read so far. you're not supposed to drive these things over 40-45 mph in 4hi? normally i could care less about that because where i moved from you only used 4wd if you were actually offroad or the streets were covered in snow and ice. seems that with a pathfinder you're not supposed to use the 4wd at all on the street regardless of how bad they are. we got about 5" of snow the other day and by nightfall the roads were getting pretty slick in parts so i put the truck in 4hi, rolled back about 1 car lenth and went on about my biz. up to about 30 mph! something is making a vibrating/pulsating sound at 30 mph. no vibration felt through floor, t-case or trans shifter, it's more of a sound. i plan on lubing the front drive shaft but i doubt that's it since there doesn't appear to be any actual vibration.
one idea i've had is that since the engine works harder in 4wd perhaps there is an imbalance with the fan or pullies on the front of the engine. although this sound does not occur in 2wd even at hwy speeds. if in fact pathys cannot be driven on snowy icey streets then what kind of shim sham deal is that!? i've owned quite a few 4wds including 76 k5 blazer, 76 scout, 72 bronco, 73 cj5, 90 montero(surprisingly bombproof) and all of them could easily be driven in 4hi up to about 55mph. if nissan can't do better than that then i'm afraid it's curtains for this pathfinder. i drive 4wds for added safety in the winter months as well as recreation of course but with this one i can't even rely on it for safety it would seem. hmm.