02 2500HD 4x4 Rear end shudder &engine noise

[Browning151]

I have an 02 Silverado 2500HD ext cab 4x4 6.0L gas, that I bought about 6 months ago, it now has 130k miles and theres a few things I need some opinions on. First off I have started noticing a sort of shudder on take off under normal acceleration a good bit of the time, seems to me like the rear end but Im not sure...the limited slip has always acted a bit wierd on this truck it has the factory 4:10 gears if that helps with a diagnosis any, and it also seems to whine alot from the drivetrain at very low speeds. Also about 2 months after i got it i began to notice what sounds like a knock on startup and then just a steady almost rapping type noise in the engine when warm...took it to the local dealer and they said its normal piston slap for the motor and to try cleaning the carbon out to quiet it some. A few other opinions from some tech friends were anything from timing chain being worn out and slapping around, rod knock or possibly collapsed lifter. Trying to decide if its worth keeping the truck with a few minor things to fix or if its time to move on to something with fewer miles. I love the truck but I dont have a ton of money to sink into it but hate to get rid of it. Thanks in advance for any opinions guys.