3- diesel engine
Next two numbers: liters per cyl
Works on 3116, 3126, 3176, 3196.
But does not apply to 3208, 3406, 3508 etc. Or the earlier ones like 343, 353, 379 etc
So basically just a random model number.
New ones c7, c9, c12, c18, c32. Those make sense. Just displacement for total engine. Just wait til they have to change the engine but keep the displacement!!!