As long as I've had this 97 Dakota it's had a tendency for the oil pressure to fall into the lower side of the normal band after the engine gets hot. I consulted an reliable mechanic and he assured me this is ok and we even checked it with a mechanical gauge...it was within manufacturer specks.
A few months later it developed a problem where it would take a very long time (like 20 secs or more) to build oil pressure if it was started when the engine was hot and had been sitting for about 5 to 10 minutes. So I went ahead and changed the oil pump. In the process I discovered that the pick up screen was about 50% plugged with sludge, and we suspect that could have been the cause of the problem.
Now 2 years later the pressure is again acting up. The last two days it has not shown as much top end pressure when the engine is above 2,000 RPM as it normally does some issue when cold; and even at 1,500 RPM it's showing the same pressure as idle (the pressure used to rise at 1,500 RPM). Fortunately it still never falls outside of the acceptable pressure but I want to resolve this issue before that happens.
I'm thinking maybe I could clean the screen again, possibly by draining the oil and pouring in a gallon of kerosene. Also I'm thinking of increasing the viscosity of oil from 5W-30 to 10W-30 (owners manual recommends both, 5W-30 preferred in cold weather). My last thought is that perhaps the oil has just lost viscosity, it's been in there for about 10 months and I haven't even put 2,00 miles on it yet (daily commute of about 5 miles one way).
Any thoughts?
A few months later it developed a problem where it would take a very long time (like 20 secs or more) to build oil pressure if it was started when the engine was hot and had been sitting for about 5 to 10 minutes. So I went ahead and changed the oil pump. In the process I discovered that the pick up screen was about 50% plugged with sludge, and we suspect that could have been the cause of the problem.
Now 2 years later the pressure is again acting up. The last two days it has not shown as much top end pressure when the engine is above 2,000 RPM as it normally does some issue when cold; and even at 1,500 RPM it's showing the same pressure as idle (the pressure used to rise at 1,500 RPM). Fortunately it still never falls outside of the acceptable pressure but I want to resolve this issue before that happens.
I'm thinking maybe I could clean the screen again, possibly by draining the oil and pouring in a gallon of kerosene. Also I'm thinking of increasing the viscosity of oil from 5W-30 to 10W-30 (owners manual recommends both, 5W-30 preferred in cold weather). My last thought is that perhaps the oil has just lost viscosity, it's been in there for about 10 months and I haven't even put 2,00 miles on it yet (daily commute of about 5 miles one way).
Any thoughts?