A leak down is a whole lot better test. A plain old compression test at least will get you a direction to troubleshoot/test from and takes less expensive tools to do. A lot of it is in the interpretation too. A good wrench head with a compression gauge can tell you a lot about your motor. It is at least a place to start getting in tune with your truck, listening to what it is saying.
Cam timing and condition is a good thing to consider too. You can get pretty low compression just by backing the valve adjustment off too loose or having a flat cam lobe. I had one of the locknuts loosen up on my 2.3L and it was reading 85psi on one cylinder. Luckily I decided to check the valves before I broke the head loose, I figured I'd blown a head gasket again. Turned out to be the intake valve was barely opening at all.
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95 Isuzu Trooper Daily Driver
86 Isuzu Trooper reliable backup
77 LUV 2wd stock beltway blaster (resting)
79 4x4 LUV project: 2.6L, 5spd, 31s (eventually)
MEPR: Man, my 4x4 makes all other LUVs look good
