What is the normal life span for a harmonic balancer? would it be worth changing if i'm in the area (removing radiator this weekend). I seem to have a harmonic imbalance at 65 mph. this is a very specific "vibration" that comes on at 65 only. 64 is fine as well as 66 mph. I've checked the universal joints, drive shafts, rear end and have had the tires rotated and balanced. If I change it out, is there a special one or type i should buy? thanks
04 GMC Sierra, 4x4
94 suburban, 4x4
84 suburban, 6.2 with Banks. Turbo 400 w/4.10's. Ex-Fire truck.
83 Volvo 760 turbo diesel. Yea it's ugly, but it gets 40 mpg on the highway...