Having 105k miles on my '04, I am starting to get paronoid about the oil pump. I havent pulled any oil psi numbers yet, but even assuming their within spec, should I replace the pump as preventative maint? I have heard/seen horror stories of them being fine, then just grenading at will.

 

Dude, dont believe all of the horror stories and the one guy on here who pushes everyone to replace everything on their truck if its over 100,000 miles, its all a lot of BS.
If your oil pump was bad it would have let go already.
Mine is original, my oil pressure is fine.
My timing chain is also original.
Yes I really do have 223,000 miles on my truck.
Stop worrying so much, drive the damn thing and enjoy it.
If you pay attention to your truck you can catch almost every problem before they happen.
The front prop shaft is your only concern if you have not taken care of that yet.

 

And doing a mechanical oil psi test will make you feel better.

 

install an oil preasure gauge so you will know when it is time, it will cost you about $50.00.

 

Yes, an oil gauge is soon coming for peace of mind, I probably wouldnt be worried if it wasn't a 4.6. When I sold my '98, it had just shy of 190k with the original oil pump.

The front prop shaft was replaced less than a week after I bought it. Wasnt taking any chances there :-)

 

an oil gauge is soon coming for peace of mind, worry about it then if you see preasure dropping

 

The best thing to prevent sudden massive failure is to spend all your time listening for ticks and unusual noises, pretty soon you will be so paranoid you wont drive it anymore and a car not driven is a car that cant fail.

 

Don't waste your time worrying about your oil pump until you get an oil gauge and have some actual numbers. It is good to be aware and know what signs mean what, but it is easy to know too much to the point of going paranoid. I have an oil and temp gauge on my 04 and I can't hardly drive without watching my numbers. So I prefer to drive my 99 that has over 226,000 miles no temp or oil gauge and the previous owner pulled the CEL and 3 amigo bulbs. I change my oil every 3,000 and don't worry, sometimes knowing less is more.

 

My point exactly.

Pay attention to your truck, get to know her, when something is amiss investigate.
Each truck is different, a odd noise on one may be perfectly fine on another.