I'm pretty sure these were addressed at 60k service, which was probably around 2009, but as I have things opened up now, I'd like to check and possibly replace shims if needed. I came across a thread that mentioned that they come in varying thickness, but I haven't yet measured clearances yet. I believe intake clearance spec is 0.006-0.010 and exhaust are 0.010-0.014. Before I get ahead of myself are there even shims for the 3.4 v8 still available? Looks like shosource only has Gen 1 & 2.