Hows water getting inside engine on 2002 Chevrolet Silverado 1500

I started getting a low coolant light come on. I added coolant and two weeks later it came on again. It happened two more times about two weeks apart again. In the mean time my oil pressure gauge started to kinda vibrate but still had normal pressure for my truck(50-80 lbs.depending on rpm). Then one morn started truck and heard lifter noise prety loud. It went away in ten secs so i want to work. After work it did the same thing so i took it to dealer and he tells me my motors shot. Help

Asked by for the 2002 Chevrolet Silverado 1500
What you say doesn't sound good. But before I would replace your engine I'd really like to know what "shot" really means. It's possible your motor's worn out or has been overheated bad in the past and really does need replacement. Have you checked to see of there's coolant in the oil? The oil would look like chocolate milkshake and that could also ruin a motor given time. A coolant leak possibly at the intake manifold would be expensive but cheaper than a new motor. I recommend getting a second opinion (you may have to pay for it) and find exactly what's wrong to set your course of action..