Loud truck got quiet (problem?)

[EvergreenRanch]

hey guys i have a straight 3" pipes out to rear axle and then y pipe to duals....they were loud as sin for awhile there but now they have gotten a bit more quiet (like 20 decibles) and i cant figure out why. no more smoke than usual. no rough idle. no precievable loss in either power or economy (maybe just alittle ). any ideas whats going on? coming up on an oil change but i dont think thats problem . tightened the belts recently, added some synthetic to the oil fill. been using different diesel stations to fill up recently out of necessity, but man im just stumped.

 

[Swany]

Maybe your hearing is going from it being so loud? Do you feel any seat of the pants lower hp?

 

[EvergreenRanch]

lol yeah thought of that too....its the general consensus of several friends familiar with my truck as well. what are the usual symptoms of an injection pump going out? like i said in my post, very slight decrease if any in seat of the pants hp.

 

[Agnem]

Timing might have slipped on you. Get it checked.