I have exactly the same result...same pressure after as before but not dropping to 0 ever. On the mechanical gauge I picked up it matches the dash. I’ll be driving this truck until it fails because I’ve paid for it twice now if you add up the repairs!
Oil pressure dropping
- Thread starter Musicars
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
I figured that even though the particles are tiny that they should not be there. Since they don't appear to be magnetic I can only assume it is bearing material. I wish there was a way to find out which bearings. Probably crank bearings but I have heard of cam bearings going out too.
I have not sent the oil out. I'm not even sure who to send out to but will look into that. I kept what I could of the particles from when the I dropped the pan. I would probably have to use the current oil because I have been so busy I am not sure I didn't co-mingle the old oil from the truck with other oil. I have my truck, the wife's car, and my daughters car and have done a few oil changes lately. I suppose the current stuff is as good a test subject as any.
I'm going to try to see if I can find the serial number on this motor. I see something up by the oil filter on a pad but can't read it. If this is the original engine I would like to keep it and repair it. If not I may look at a different motor.
Yes, these motors are not cheap to repair or replace. I hear aboout all these motors going to nearly 300,000 miles and some way more so I expected more. But who knows how it was treated before.
My big fear is it breaking down on a long haul. Planned on taking it up north to put the dock in this weekend. A little leery of that now.
Curious as to where you hooked up the mechanical gauge. I assumed it had to be connected to the same place as the original sensor.
clandr1
Full Access Member
Blackstone Labs is the gold standard in oil analysis. I've sent numerous samples to them.
https://www.blackstone-labs.com/
Thanks, I had just found then on the internet and was about ask if anyone used them. Their FAQ section cracked me up but also had me concerned that their turnaround time might be a little slow. I'll give them a shot.
Took the truck on 125 mile trip north this weekend. Started at 30 psi of oil pressre on the highway. At about 100 mile the pressure was at about 27 psi on the highway. By the time I got up there it was still at about 27 and then idled with about 8 or 9 psi but the warning never was triggered. Then the next day drove 60 mile south to a funeral and sixty miles back up north with oil pressure starting at 30 then maybe ending at 27 - 28 psi. Drove the 125 mile back with the same pressure. It was a hot weekend with temps in the 80s and 90s in town and 70's and 80s up north.
There is one change. We noticed a weird scratchy rattle when I rev the engine. It does not follow the rpm exactly it kind lags the way a cracked flex plate sound lags but it does not sound like a flex plate. Sounds near the front of the engine but not sure if it is on top. Have to wait until I can get the wife to run the throttle while I use a stethoscope on it. It make the sound at idle but gets louder as it revs.
I am still surprised the oil pressure dropped so quickly originally but has not continued dropping significantly.
There is one change. We noticed a weird scratchy rattle when I rev the engine. It does not follow the rpm exactly it kind lags the way a cracked flex plate sound lags but it does not sound like a flex plate. Sounds near the front of the engine but not sure if it is on top. Have to wait until I can get the wife to run the throttle while I use a stethoscope on it. It make the sound at idle but gets louder as it revs.
I am still surprised the oil pressure dropped so quickly originally but has not continued dropping significantly.
clandr1
Full Access Member
Have you tried running seafoam in the oil? Only thing I can think of is there's a blockage of some sort in your pickup tube and it's causing the pressure to be low as a result. You've already replaced the pick up tube o-ring and the oil pump, right?
Have not tried Seafoam, but I did squirt brake cleaner down the pickup when I had it out. I never actually checked to make sure the tube was completely open but the brake cleaner ran through easily in both directions and the screen was clean when I took it out.
Also, I found the source of the rattling noise. I used a long wooden dowel as a "stethoscope" and tracked it down to the A/C tensioner. I saw another thread on this site discussing this issue. Now I just have to figure out if it was just the tensioner, the clutch, or the compressor. In my case it was louder with the A/C off and got better with it on. Later in the day it threw the belt so something stopped turning. Never squealed, just rattled.
The fun never stops!
clandr1
Full Access Member
The good news is the A/C belt tensioner is cheap and relatively easy to replace. I just installed one about three months ago. Sorry you're having trouble tracking down the oil pressure issues, I know it can be frustrating.
