Here's another Bulletin announcing Chryslers experiment with hydraulic lifters in some Slant 6 engines in 1978.

Notice there is NO mention of a different rear cam bearing. This would imply that the oil groove is in the camshaft journal and not in the bearing. Makes sense too because that way there is no worry about which bearing is in the engine block and one could swap in a hydraulic or solid lifter camshaft and not have to change the bearing in the block.

Hooray, you found your TSBs!

I don't have an '81-up FPC handy to compare part numbers with this bulletin and see what was kept and what was changed for the formal rollout of hydro lifters on the slant in '81. A grooved cam rear journal makes sense. Wonder if anyone on the board here has ever run across one of these engines.

Any chance you can find the "1 and 6 plate" bulletin from '75-'77?

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