i have a 1999 cummins with 109,956 on it.  The truck starts runs and performs awsome and holds its oil pressures and temp perfect, and it doesn't ever smoke no white blue or black.  MY issue is that it has a straight pipe on it and its only 3 inch due to the muffler and cat rotted and removed due to lack of funds to replace them, and now the truck has what sounds like a tick that comes out of the tail pipe.  And mostly only when idle.  the motor bay is quite with no ticking or knocking anyone have any clue.   ps this is my first cummins so i dont know what it should sound like.  

I happen to have 4" all the way back and that works fine no muffler no resonator or cat.  So I would thing it would be very minimal to just have a pipe alone run to the back or cheaper off to side before the rear wheel. My truck did not come with a cat

have you ever heard a ticking out of the tail pipe on yours

I'm 5" to the back and I can't say I hear a tick. Only thing that comes to mind is to check to be sure the turbo turbine is not rubbing the housing. I'm sure others will chime in.

Did you ever take out the rotten muffler or resonator? That could be your ticking noise

Yes I did delete the resonator and the muffler the tick has seemed to work itself out but now like I said im new to Cummins and my 99 has white smoke out of the blow by tube not a lot but noticeable at a stop and idle only when it gets hot.  The truck has no loss of power or hard starts no smoke except a little black puff on start up.  If I take the oil fill off there is a small amount of white smoke out of it but I did the cap test placed It upside down and it didn't move or blow off just vibrated from the motor my question is is this something to worry about or is it ok I hold perfect temps and oil pressure all day can drive it 50 miles at 60mph and it stays fine. I will start a new thread to

That's pretty normal. There's always going to be some amount of blowby and positive crankcase pressure. Nothing to worry about unless you're puffing like a train out the oil fill cap.

That's pretty normal. There's always going to be some amount of blowby and positive crankcase pressure. Nothing to worry about unless you're puffing like a train out the oil fill cap.

 

Or pushing large amounts oil out the vent.