CM870 Mystery pieces

[Waterloo]

The gravel you found are a form of kidney stones, very common in the 870 motor, they tend to appear as the motor ages. You really need to watch where you purchase fuel, a good dose of cranberry juice with every other fuel stop may be in order. If the stones persist, you may need to get the truck to a certified Cummins urologist to properly diagnose... I am sure Mr Hagg or Unilever can point you in the right direction. Not something to mess with, and your truck will thank you. ;-)

Sorry, could not resist.