i'm just saying it MIGHT be the CV, but i highly doubt it. and yes it would have made his truck shake. It's not the tires, his tires are not balanced at all. and they're almost the exact tire. The tires ran fine on the old setup, it's not the tires, I took the tires off and did a test running the driveline up to speed, it vibrated like hell, it's not the tires, I took the brake drums off thinking they were hanging up, it's not the tires. I just hope when i put it in it's fixed, because ya, i don;t think it's the CV either, but I want to know more about them, just in case. I'll know this weekend IF I get my driveline back from him...:eeek::haha: He definitely changed up the balancing on it, the weight in one spot up towards the CV was definitely larger...which was where the vibration was most prevalent...:eeek: