Im in the market for a good used truck, but im wondering how many miles is too many for the 5.3? Ive currently got a 2002 yukon with a 5.3 and a smidge over 100k and it still runs like a new one, so I guess they are good for 100k anyway. So my question is, how many miles can you expect to get out of the average 5.3? 150k? 200K? 250+K? If you have a high mile ls motor please chime in and tell me what to expect on the average.