A while back, I cranked my tbars and added shackles to get about 2 inches of lift. I was pretty much running my studded snow tires back and forth to skiing, and had not had it aligned. I did have it aligned in the spring, and swapped my regular tires back on.

The alignment was out of spec in camber on the drivers side, but all else looked good. The Blazer sa for a while , except for some short in-town trips. Now That I have moved, and am taking longer trips, I have noticed a vibration and associated sound at highway speeds, but only when the front "unloads". By this I mean when I go over some wavy road at 65-80 mph, just as I pass over the high point, and there is little weight on the tires (BFG AT) and the suspension drops down. With normal driving there is no noise / vibe. The noise is like running over very light rumble strips.

Is this likely to be tire noise, or do you think this may be the CV Joints binding a bit and I should crank the bars back down a bit?

 

My friend had a similar problem with his toyota. i mention this because both front suspensions are similar. when he set his tbars back down his ride quality improved. either way i would still check balljoints and cv shafts.

 

ok, If you're getting the vibration when the suspension "uncompresses", if you know what I mean, The only thing that makes sense in my head are the CV joints binding. When the suspension compresses, it'll straighten the axles out, putting less of an angle on the CV joints, but when it rebounds, it generally bounces above the normal sitting position of the suspension, putting an extreme angle on your CV joints and causing them to bind in your case because you lifted the front 2"... a rule of thumb I've seen is 1.5" of T-Bar lift in the front. (Personal experience doesn't apply to me here, just hear say.)

If you look at a stock Blazer, the suspension is adjusted from factory so the CV joints are straight at rest, that way either way the suspension goes it won't bind, lifting it you've got a constant angle int he CV joints and if that angle is too extreme, you can bind them up, and I think that's where your vibration is stemming from.

Hope all this BS is clear... kind of puked that out lol.

I'd crank it down half an inch and see if that helps the vibration. Hopefully that's all it is, but it should be.