Since I have installed my FabTech 3.5" spindle lift with rear blocks I have had a slight vibration at about 65-70mph. It wasn't bad so I thought it was the larger tires. Now the vibration is getting worst. I have had the tires rebalanced by the place I bought them, checked wheel bearings, and I also checked pinion and tranny angels and they match. Anyone else have an idea. I might take my truck to another shop to check the balancing but I don't want to have to pay for it since the place I bought them does them for free. Any ideas would be great.

 

Just a thought did you use longer U bolts and are they tight .sometimes the nuts bottom out on the threads but the springs not tight on the axle Try some spacers under the nuts.Good luck .Phill
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