2003 Dodge Durango RT 4x4 5.7 V8, 160k miles. Oil pressure seems fine when engine is cold. When warm, the oil pressure drops intermittently and engine light comes on. Then pressure increases and light goes off. More frequently at low rpm. We replaced oil and oil pressure sensor. No change. Mechanic seems to think it could be 50/50 chance of oil pump or main bearings. Hesitant to spend money on oil pump only to find it's the bearings. Mechanic says I should cut my losses and sell the vehicle.
So my question is : is there any way of monitoring/testing/recording actual oil pressure over a period of time with the engine running cold, hot, low revs and high revs? Any other way of determining the cause of the low pressure without junking the vehicle or spending a fortune?
Would greatly appreciate some guidance.
is there any way of monitoring/testing/recording actual oil pressure over a period of time with the engine running cold, hot, low revs and high revs?
Have you considered installing an aftermarket mechanical oil pressure gauge?
I had wondered whether there was such a thing and what information I would get. I've already tried replacing the electronic sensor twice. I guess a mechanical unit would either confirm an oil pressure problem or a problem with the electronic sensor? However, the fact that the pressure seems good when the oil is cold (and thicker?) but drops when the oil is warm and at low rpm (but better but still intermittent at higher rpm), makes me wonder what the next step should be. Mechanical o/p gauge?
You need to hook up a mechanical gauge at least temporarily to get a true picture of what's going on.
Thank you. Will do so.
I had wondered whether there was such a thing and what information I would get. I've already tried replacing the electronic sensor twice. I guess a mechanical unit would either confirm an oil pressure problem or a problem with the electronic sensor? However, the fact that the pressure seems good when the oil is cold (and thicker?) but drops when the oil is warm and at low rpm (but better but still intermittent at higher rpm), makes me wonder what the next step should be. Mechanical o/p gauge?
wonder what the next step should be
Do as @chucktobias suggested, verify that you have low oil pressure. Eliminate any possible false reporting issues with the electronics via a gauge/sensor/wiring.
Sure, you can use a mechanical gauge to accomplish this.
Thank you. Will do so.