Oil pressure problems

[CrownVic92]

HI all new here.
I have a 1992 Crown VIc Lx with 4,6L V8 engine. I'm having problems with oil pressure at idle. If im drivng it stays over 30 but when Idling goes as low as 5psi. And some guys told me that even if I change my oil pump theres already damaged done to the engine and that I'd have to rebuild the engine. And I'd like to know if thats true or not.(motor isn't knocking) And If it's true I would like to know what I should do : A:Change oil pump and drive it until motor starts to knock and rebuild engine or put new engine in or B: Putting 15w40oil instead of 10W30 and putting in a Lucas Oil treatment and run it as long as I can and then rebuilding motor or putting new engine if engin starts knocking?

Or do you guys have another another suggestion for me?

[DuceAnAHalf]

10w30 is too heavy Ford recommends 5w20. Are using an actual oil pressure guage? because the one in the dash is an on-off switch. And you dont really rebuild the 4.6 you replace it with a low milage used motor.

[Johnnyiroc]

actually in 92 they used 5w30. I think you "could" replace the pump if you wanna do the work yourself to save some cash. But that is almost the same amount of work as changing the whole engine with a lower mileae one. It is your call, you may find you will be replacing the engine anyway if the pump does not cure the problem. Are you positive the gauge is right? Sometimes the low oil pressure is caused by the common too thick of oil thing ...wear starts opening up the surfaces allowing the oil to just run thru the bearings and so on, thus reducing pressure. Either way the repair is not something I feel like doing right now. hope you are ambitious.

[CrownVic92]

I'm using and after market oil pressure guage. And you can here the engine idling really low when oil pressure goes down. So you guys are suggesting I tough it the way it is as long as I can and then change engine?? I don't think i'll find one with lower mileage lol....thats my prob car hasnt run 3\4 of its life only got like 79477km thats like 40something miles on it.

[P71Times2]

Actually, Ford's recommended 5W-30 in the 4.6L engines up until 2001, and then when with the 5W-20 recommendation for emission purposes.

I have a copy of a 1997 CVPI "Extreme Conditions" Supplement and for those conditions they recommend 10W-30 oil.

This was from a recent meeting (2005) between the Ford Police Advisory Board and Ford Fleet Services:

"5W-20 Oil

Extended discussions were held, both in closed PAB sessions and in open sessions with Ford Fleet, on the use of 5W-20 oil in the 4.6L CVPI engine. In 2001, Ford changed from 5W-30 oil to 5W-20 oil. Lighter oil causes less friction which increased the fuel economy of the 4.6L V-8 and Ford’s overall CAFE rating.

Ford makes it clear, all the way down to putting 5W-20 on the oil filler cap, these newer engines should use 5W-20 oil. Not all agencies do that, including some extremely credible and influential agencies that use oil as heavy as 15W-40. Ford Fleet indicated that its oil viscosity recommendations should be followed, however deviating from those recommendations won’t void the warranty."