Yet another Yukon with engine tick and low oil pressure

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donjetman

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Thanks for looking up the specs, really appreciate it! Well I’m at 8-9 psi at 600 rpm in drive, driving around 70mph oil pressure sits at 38-40 psi - from the minimum oil specs you provided I’m within range.

Yeah might as well have the sensor changed when the oil pump is going to be changed.

I just searched and there are some companies round here who do oil sample analysis - I’ll get in contact with them and see what it is about - would be good to get an indication of what the ticking/knocking sound is likely causing. Thanks for the suggestion.
Here's a video for ya:
 
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YukonDK

YukonDK

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Took a look at the oil dipstick today. It looks like I have metal shavings on the tip of it and the oil also has small black spots. Will reach out to oil analysis company on Monday and see if they can help.

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Geotrash

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Took a look at the oil dipstick today. It looks like I have metal shavings on the tip of it and the oil also has small black spots. Will reach out to oil analysis company on Monday and see if they can help.

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The dipstick can't give you a big enough sample to say. That could've been from anything, including manufacture of the dipstick itself. I agree with your inclination to have oil analysis done, and I would cut apart the oil filter and inspect the element for metal shavings also. The rule of thumb for visual analysis of the filter media is if the actual metal material (not carbon) from the filter is enough to cover your pinky nail, it's time for concern. I use a magnet to collect ferrous metal from the filter media. In general, aluminum wear creates gray dust and tiny blocky chunks, and steel wear generates tiny slivers. Anything big enough to read a part number on is obviously a problem. :p

That said, are you still getting the rather loud knock at cold startup that you posted in your first video? I just gave that another listen and it seemed pretty loud for piston slap. The 6.2's especially get some good piston slap at cold start but neither of mine have ever been quite that loud.
 
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YukonDK

YukonDK

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The dipstick can't give you a big enough sample to say. That could've been from anything, including manufacture of the dipstick itself. I agree with your inclination to have oil analysis done, and I would cut apart the oil filter and inspect the element for metal shavings also. The rule of thumb for visual analysis of the filter media is if the actual metal material (not carbon) from the filter is enough to cover your pinky nail, it's time for concern. I use a magnet to collect ferrous metal from the filter media. In general, aluminum wear creates gray dust and tiny blocky chunks, and steel wear generates tiny slivers. Anything big enough to read a part number on is obviously a problem. :p

That said, are you still getting the rather loud knock at cold startup that you posted in your first video? I just gave that another listen and it seemed pretty loud for piston slap. The 6.2's especially get some good piston slap at cold start but neither of mine have ever been quite that loud.
Thanks for the input, appreciate it. Yeah it seems like oil analysis is the way to go, didn’t have to time to call them today, got off from work to late. It will probably give me an answer, so far I have probably just been trying to convince myself that it was not that bad since the engine 110k miles, but the engine is probably on borrowed time.

Yes it’s still very loud on a cold start. The below video is after the o ring change and a morning where it was 41 Fahrenheit.

 

Geotrash

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Thanks for the input, appreciate it. Yeah it seems like oil analysis is the way to go, didn’t have to time to call them today, got off from work to late. It will probably give me an answer, so far I have probably just been trying to convince myself that it was not that bad since the engine 110k miles, but the engine is probably on borrowed time.

Yes it’s still very loud on a cold start. The below video is after the o ring change and a morning where it was 41 Fahrenheit.

Sounds like it's at crankshaft rotation frequency also, which is a good clue that it's not valvetrain related. I wish you luck and we will be here when you have more info.
 

j91z28d1

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Sounds like it's at crankshaft rotation frequency also, which is a good clue that it's not valvetrain related. I wish you luck and we will be here when you have more info.


it's the craziest thing.. it doesn't sound like valve train to me either, but I've never heard anything knock like that when cold and go away. any time I've been around bottom end stuff, like main or rod bearings they all get much worse than hot.. can almost sound OK when still cold on thick oil.


possible it's a stater rubbing the flywheel? or balances that's completely come part? I'm so confused by this truck.. cold, 40psi oil pressure and it knocks, gets warm, drops to 11 psi and gets quiet.

I got nothing.

one of my first engines I build as a kid, I added a windage tray and didn't get a clearanced enough a rod hit it. that's the closest thing I can remember hearing to this.
 

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