2003 Durango 4.7L No Oil Pressure
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2003 Durango 4.7L No Oil Pressure
My daughter has a 2003 Durango with the 4.7L engine with 170K miles on it. I started it yesterday and it has no oil pressure and the lifters are rattling. The oil level shows full. She can't remember when the last time she changed the oil. I'm going to change it this afternoon with 5W30 oil. A few questions:
Is the rotary oil pump under the timing chain cover prone to failures?
What are your opinions of the STP oil filters? Autozone has a special on them.
If the oil pump is bad, how hard is it to replace?
Thanks,
Danny
Is the rotary oil pump under the timing chain cover prone to failures?
What are your opinions of the STP oil filters? Autozone has a special on them.
If the oil pump is bad, how hard is it to replace?
Thanks,
Danny
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Joined: Sep 2010
Posts: 396
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From: Buffalo, NY
I just posted my 4.7 rebuild thread where I put a bunch of tips on this motor, but to answer your questions:
No, the oil pump is not prone to failure, however the pickup tube can crack on it, and the screen can be clogged with debris which would also cause low / no oil pressure.
Changing the pump is not difficult, but getting to it is a real bear! If it's 2WD no problem, you can drop the pan. On a 4wd you'll have to drop the front diff and driveshafts to get the pan off, and most likely at least loosen the steering assemblies. The pan must come off as the oil pickup is bolted into the pump from below. You'll also have to pull all of the timing components to get the pump off, replace them when they go back in, or at minimum do the guides and tensioners.
I know the lifters are rattling, but make sure the sending unit isn't bad. You can pull it and hook up a mechanical gauge to see what your pressure is really like. Oil pumps rarely (IMHO) just "fail" all of a sudden.
Regarding filters, everyone has their favorite brands and horror stories. My opinion is as long as it's changed frequently even a cheap filter is better than a dirty one!
There is also an oil pressure relief valve built into the pump, but I don;t know if you can get to it without removal, and I think it's just a spring and a ball anyways. Not servicable that I know of.
Bob
No, the oil pump is not prone to failure, however the pickup tube can crack on it, and the screen can be clogged with debris which would also cause low / no oil pressure.
Changing the pump is not difficult, but getting to it is a real bear! If it's 2WD no problem, you can drop the pan. On a 4wd you'll have to drop the front diff and driveshafts to get the pan off, and most likely at least loosen the steering assemblies. The pan must come off as the oil pickup is bolted into the pump from below. You'll also have to pull all of the timing components to get the pump off, replace them when they go back in, or at minimum do the guides and tensioners.
I know the lifters are rattling, but make sure the sending unit isn't bad. You can pull it and hook up a mechanical gauge to see what your pressure is really like. Oil pumps rarely (IMHO) just "fail" all of a sudden.
Regarding filters, everyone has their favorite brands and horror stories. My opinion is as long as it's changed frequently even a cheap filter is better than a dirty one!
There is also an oil pressure relief valve built into the pump, but I don;t know if you can get to it without removal, and I think it's just a spring and a ball anyways. Not servicable that I know of.
Bob
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Joined: Aug 2013
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From: Wisconsin
You said she couldn't remember the last time she changed the oil, so it was probably too long ago and the viscosity had broken down. The consistency of oil becomes more like water as the viscosity breaks down which also will cause the pressure to drop as it is much thinner.