I've got a 98 2 door Tahoe with the good old 350. Truck has 235k miles on the clock. A year ago I had a bad coolant leak and changed the lower intake manifold gaskets, water pump and valve cover gaskets. Changed timing chain and sprokets and oil pan gasket while I was at it. A year later I still have a slow coolant leak. Its much, much slower than before. It seams to be internal because there are no visable signs of leaking. I probably loose 10 to 20 ounces of coolant between oil changes. I'm seeing no signs of coolant in the oil or vice versa. No signs of vapors/condensation under the oil fill cap. The only signs I'm seeing is a slightly to moderately wet exhaust and a sweet coolant smell when I get out of the truck. The truck runs great all the time and doesn't overheat. Any other tests to perform before I tear into this project? Am I on the right path to solving the coolant leak. Thanks