I just inherited a 2003 RAM 2500 w/ 5.7L engine from my bro-in-law back on 3/26 and it's been parked ever since while I've been getting it ready for state inspection. The truck just rolled over to 275K. I know for a fact he kept it serviced on schedule since he used my NAPA account to get his parts. I just had it run through state inspection and tagged yesterday. So I changed the oil since he said it was time - 5W30 oil and NAPA Gold filter however I put in 8 qts. of oil as opposed to the 7 (was side tracked - don't ask). So afterwards I let it run for a good bit so as to check the trans fluid and such and then take it out to fill the gas tank and no issues at all. Jump in it this morning heading out to work when about 2-3 miles down the highway at 60 MPH the "check gauges" light comes on and the oil pressure gauge is at 0. It does this a few times bouncing back and forth between normal and 0 and finally settles down at 0. I was close enough to head back home. By the time I get there the OP gauge is still at 0 and the lifters are ticking but that's it - no real bottom end noise. I didn't want to let it run any longer than needed. Checked the oil and it's above the full mark (hence the 8 qts.). I had to leave it as I was running late for work.

Suggested areas to start looking (after I run a mechanical OP test when I get home)? He said he's never had any issues at all and it seems funny it does this right after an oil change. Possibly a faulty oil filter? Would the extra quart of oil cause too much foaming?

Just looking for some input before I start thinking the worst (i.e. dropping the pan or doing the pump).

Thanks for your time,
Brian

 

Just replace the oil pressure sensor first.. 275k miles is a lot for those sensors...

It's prolly just the sensor on it's way out.

Also Drain that extra Quart out of there.. you don't want to bust any of the seals that are already very old...

If the new sensor doesn't fix it then I think you might have a bad oil pump.

 

What type of oil did your bro in law use?
Dyno or synth?
Also what did you put in. Dino or synth?
If he's used dino for 270k miles and you've just dumped synth in, then the synth may have dislodged a load of crap out of your engine due to synths cleaning properties blocking your oil pump strainer. Just a thought???

I also agree with Izero. Get rid of that extra quart. Does a lot more potential harm than good.

Al.

 

Tried posting this last night but kept loosing connection to the server -

I drained the extra qt of oil. Removed the oil filter and it was basically empty. No oil came running out while removing it like the one before when I did the actual oil change (which tells me there was oil pressure before). There was a bit of oil in the bottom but that's about it. However, as I stated, right after I changed the oil back on Tue the gauge showed being in the normal range and didn't skip a beat even after letting it run for a while to check the trans fluid and heading to the gas station. How could there be enough pressure to kick on the OP switch but not pump oil into the filter??

Anyway, I filled and installed a new oil filter and also installed a mechanical OP gauge. Fired up the truck and the OP went straight to 60 psi as the lifters all quieted down as they pumped up. Again, no noise in the bottom end at all. Jumped in and within 1/2 mile to the highway and on the highway the OP was dropping and came pretty close to hitting at 0, running between 5 - 10 psi even at RPM. Headed straight back to the house. Let it sit for a bit to cool down and started it up again - OP went to right about 30 psi and then started to drop. Under RPM it didn't want to climb at all, in fact it kept dropping. Shut it down and went inside for a Coors Light.

As far as the oil used - I used the same exact NAPA 5W30 dino oil as my bro-in-law had been using since day one. I have always been under the impression that these crank-driven oil pumps on the 5.7 are pretty much rock solid and not very susceptible to going bad - true or not?? I'm just having a hard time wrapping my head around why there was oil pressure when I received the truck and now there isn't especially when the only driving was to take it for the state inspection and to get gas (all back roads, nothing over 30 mph and within 1 mile). Only work done on the truck since I got it was pretty much minor stuff just to pass inspection. Hardest thing was replacing the the exhaust gaskets.

I have no problem doing what needs to be done but the whole thing making no sense at all is what's really bugging the crap at of me. I could understand if I had had the chance to have put some miles on the truck but it's like the OP went south just from the truck sitting in my yard waiting to be driven again - go figure. Guess the next step is to drop the oil pan since it needs to come down anyway if I go the route of replacing the oil pump.

So there you have the latest......

Thanks,
Brian

 

Almost sounds like all of the oil is staying up in the heads from clogged oil return holes. You might pull a valve cover and see if it is all sludged up.

 

Dropped the oil pan yesterday. For starters there was a good bit of "slushy" debris which was sitting in the v-shaped area under the drain plug hole. Also the sump area of the pan was not level and had been pushed in from the outside a bit (improper engine lifting..??) allowing more of that debris to sit down in the crevices created by that. So, the best thing I could assume was that when the engine would first be started I had pressure through normal operation. However, as soon as I would start driving, creating more flow and recirculation along with the oil temp rising, that "slush" would get sucked up to the screen and clog it. That compounded with the screen being somewhat clogged would completely restrict the normal flow of the oil. As the engine would be shut off and allowed to sit, that "slush" would then have time to settle back into the areas and it would all happen again at the next start up.

Why all this came about right after doing an oil change?...who knows. It was definitely a time bomb waiting to happen. I just need to look at it as being fortunate and being able to address it now instead of when I was someplace too far away to repair it myself.

In any case, I cleaned up the pan, scraped the sides, wire brushed it to remove the caked on crud, hammered it out to straighten it, completely cleared out the pickup screen & tube, etc. So now at initial start up the oil pressure goes straight to 70-75 psi. Once it reaches normal operating temp the oil pressure is running at 65 psi at 1700 rpm (65 mph) and 45 psi at idle - a tad bit better than the 5 psi it was running

Thanks for the replies and help - greatly appreciated.

Brian

 

Hmmm I was right about the crud. Just not about the synth. :-)
Well done on the repair.
It Would have been nice to have put a 6.1 oil pump in there while it was all open.
Nice lil performance upgrade.
Al.