low or no oil pressure on 2004 Dodge Ram 1500

how much should it cost to repair an engine with little or no oil pressure. also, what causes this problem especially when there is plenty of oil in the engine?

2 answers 1 comment
See previous answer but low oil pressure can be caused by a worn oil pump, an engine that did not have its oil changed frequently enough. Oil needs to be changed periodically as it "breaks down" over time of use and looses is lubrication qualities. If an engine's crankshaft wears due to dirt and debris circulating around the engine the bearings wear and the "gap" between bearing and crankshaft gets greater and needs more oil pressure and volume to fill that space. If the oil rings wear the engine will burn and consume engine oil.
Thanks for your answer. I am being charge around 2000.00 for this repair. Is this in the ball park for what I should expect to have paid. And, being that this truck is only 6 years old but has 170 thousand highway miles, (a)should I expect more problems and (b) should I think about trading it? I am concerned because I researched this issue and found that there were a lot of complaints about this problem on this particular vehicle.
I have a 2004 with the same engine, but fewer miles. I have read in many sources that the designed-in life expectancy for the engine was 150,000 miles.....