Silverado purchase

Looking at buying an older Silverado 4X4 XCab with high mileage, then rebuilding the engine. What engine tranny combo is most reliable ? Is there a good manual combo ? I do want v8 minimum.

My neighbor has a Suburban with the 5.3 with 60,000 miles and it has held up very well. No problema at all. Also gets good gas mileage considering what it is. If I were to buy a Chevy I would probably go with this engine. If you buy a high mileage truck the engine may still be good. They seem to go a long time. You can get low mileage engines pretty reasonable from the junkyard. www.car-part.com.

I've got an 86 silverado with a 350 (158,000 miles) and it still runs great. The tranny is a 700r4, "the crappy one", but it still shifts strong and there's almost no delay in manual shifing. The trucks been abused quite a bit (heavy trailers, full throttle over hundreds of miles on the highway, been hydrolocked twice, offroading...) and it's still running strong. I (and the previous, original, owners) have maintained it very well, that's the key.