If there is no specific problem with any particular cylinder (burned valve, blown HG, etc) but only normal and even wear then doing a compresson test (first dry, then wet) will give you some info to work with. A leakdown test (will tell you just where the leakage is--hissing out the exhaust?--the intake manifold?--the oil cap? -- together they can give you a sense of a baseline. Are you using (burning) oil? Yes?----then you should see a dramatic jump in compression when doing the wet test. No?--then a modest jump (let's say going from 150 dry to 165 wet) would be normal. A radical difference between cylinders would indicate a problem of one sort or another (worn or broken rings, scored cyl. wall, etc.) In other words--you have nothing to lose by doing the test(s). -- Dave