Originally Posted By: BrocLuno
Originally Posted By: Chris142
My 302 and 350 Chevy's both ate cams at low milages. I consider that a failure. My 350 got a rod knock soon after the new cam was installed. Had a 340 Dodge drop 2 valves,destroyed the 2 pistons.My boss' wrangler needed rod bearings @174K due to a light knock, Bearings were into the copper. My 86 Mitsubishi needed a valve job @35k ...crankshaft broke @44k. A fram oil filter came apart in my moms dodge omni and plugged the oil feed to the head. ruined the cam and head.
Cam failures in some generations of SBC's were common, and NOT related to the oil. They had soft cores. AND, if they just stuck in a new cam w/o doing a complete rebuild, the rod knock was the least of your worries.
Once a cam starts shedding metal, it goes all through the engine by going past the filter on cold starts (by-pass). Embeds in any soft metal like piston skirts and bearings and just eats stuff up. Once a cam goes, they owe you a complete engine teardown, boil-out, and rebuild ...
both were rebuilt engines with aftermarket cams and lifters. broken in correctly by me.
my friend recently lost a rod on his 04 wrangler. he only uses factory filters and chevron oil changed every 4k.