The first-gen 4.0 AJ-V8 did have those chain issues you mention, as well as Nikasil bore-wear. Now, the high-sulphur fuel that caused that problem is long gone, but the Gen1.5 AJ-V8, as well as the Gen2 and Gen3 versions (4.2 and 5.0 respectively), have all had cast iron liners as well as better...