Hello everyone I posted a question a couple of months ago and got some helpful info here thanks to all , I had a growling grinding noise in the front of my 97 Blazer and mechanic replaced wheel bearing assembly 350.00 no change I finally found some infor and I took the nut off the axle where the sending unit is and sprayed wd 40 all over it , there must have been a bad connection {had read lots of reports of moisture getting in there} anyway I think the main problem was that I almost never use the 4 wheel drive and it just froze up , now I will put it in 4WD every week for a little while to get everything working again. all good now , thanks again