Hey guys, I just bought an 02 Z71 extended cab Silverado about a month ago. The truck is in great physical condition, engine is strong, no transmission slippage. The truck does have a lot of miles on it, 240k. I bought the truck to help out around the house and to have something to drive in the snow. I bought it from a dealership that checked all the major components out and said it was good to go. For about the last week to week and a half I've started to notice a slight jolt/clank or grab when I take off from a stop. It feels like there is some slack in the drive shaft or differential. It shifts through gears great, and the jolt doesn't occure when shifting. It mainly happens when still in first within the first couple of seconds from take off. I also notice it if I cost up to a stop sign, roll up and get back on the gas. From what I've read it sounds like it is my U-Joint? I didn't notice the problem when I test drove the truck or even when I got home. If the dealership greased the joint before I picked it up, could be a reason I didn't notice it till now? I will end up taking it to my mechanic to get it looked at, but I would obviously like to know, or have a good idea of what the problem is before I take it in.