Hello I have a 98 Blazer LT 4x4. I just had the front end completly rebuilt- balljoints, idler/pitnam, tierod ends etc. Anyways while driving I get a slight vibrationand roadnoise while traveling at speeds between 50 and 60 MPH.Speeds below 50 no noise, speeds above 60 no noise. Just in between. I waswondering if this a tire issue. After I rebuilt the front end I had the truckalinged and tires re-balanced. So im wondering if thisis a balance issue. I inspected the tires and there is a slight bulge on the sidewalls of two of the tires.Is this an indication of a broken belt or is this normal? Cuz if it is a broken beltI thinkI found my problem!Also the sound is not load sensitive and is the same weather in 2 hi or 4 hi. So I think I ruled out any driveshaft/4x4 issues. Any help would be appriciated. Thanks!

Might want to check your alingment.

Rotate your tires to see if the vibration moves. Sometimes depending on how long the tires were on the front with bad parts they could have developed a wear pattern and this might be the cause of your noise. Some times during the manufacture of the tires there will be some small amount of sidewall overlap in the casing/mold where the parts come together. It is more noticeable with radial tires than with bias ply. Unless there is cracking in the casing I would not worry to much about it.

A slipped steel belt usually looks like a lump under the treads.