iv only had my 95 ram 5.2 w/150k for about three months and i finally got around to changing the plugs and i found that all eight of them had major ash deposits and was causing it to run a little rough. im pretty sure ash deposits comes from oil burning in the combustion chamber. so if every plug has it, am i correct in saying that its probably a failed belly pan gasket that i have been reading about? i seriously doubt all 16 valve seals are leaking. any ideas. thanks guys.

 

Yes, with 150k I'm sure the belly pan gasket is blown...