Farmboy12357

How common is it for a camshaft to go flat or start to go flat on our engines? thinking about doing a cam lift test to see how much she is in spec. just wondering if it happens a lot. Haven't heard too much about it. truck has 345,000 miles

93flatbed

Rare, but if you have the time and tools I'd love to hear the results. Maybe the way I can convince the wife I really need to get another cam before the one in my pile goes bad. Haha.

Crazy Matt

Doubtful that a cam would go flat. Ive seen a few engines with 500k and the cams look new.

92roughstock

My can looked nearly new at 350k when I replaced the gasket behind the gear case. Had to get in the right light to see the wear marks. Couldn't feel them with my finger nail, though.

bill-d-c

I used to own a 92, 180K miles on it. It started to idle rough, as time went on it began to idle even rougher. Called a friend of a friend who is a diesel mechanic at one of the largest Dodge dealers in Kansas. I tell him the symptoms, he immediately says flat cam. He says the 12V's are notorious for it. I've been on this and other Cummins forums for 2 years and had never heard of anyone having an issue with the cam shaft. Well, long story short, it was my IP. I don't know what to make of what that mechanic told me other than he is wrong.
Bill

j_martin

Aren't camshafts case hardened. If they wear a few thou they will then rub that lobe completely off in short order.

Never seen it in a Cummins. Lost a few chebys, though.