New serpentine belt after about 4000 miles! Apparently the idler pulley deformed and a sharp point developed, started to cut the 8th rib off!
If you change a serp, take the time to clean out all the grooves on the pulleys! The PS and the AC pulleys were very loaded with old belt material!
Also, for anybody with N55 plant, if you ever removed the fan you know what a pain in the ass getting the fan past the lower hose is—been wanting to do this for almost two years:
I cut the spar that tries to cut the lower hose every time in/out and it dropped in with gravity didn't even have to push. I only tapered the end I didn't remove the spar. I can't believe that is factory design.
Prob 60-70% of the original strength and there are 5 more so I have zero concern of loss of strength.