Oil pressure issues

[Easiski]

2000 Yukon 5.3 I'll start by saying I have read all the relevant threads, but am a little concerned. I had a loss of oil pressure recently in very hot weather on a long motorway trip (250Kms). I also got a nasty tapping sound from the engine. I had to return home where I put some oil additive in the engine, and the pressure seems OK, but the furthest I've driven since is about 60Kms each way.
I spoke to an 'expert' online who advised changing the oil pump and have all the parts required BUT ... as per previous problems, local garages don't want to attempt the job which seems to be rather complicated - I've looked at several YouTube vids. SO .... should I change the oil again? It was changed and filter replaced recently, and he found some sludge in the bottom of the oil pan, but didn't drop the pan due to above complications.
Do you knowledgable guys think it's worth flushing the system and changing the oil again? He put 5W30 in it as far as I can remember, which seems to be the right oil. I need my car daily, and the nearest american car garage has a 3 month waiting list and even then won't do the work immediately.
Retired, arthritic old lady in FRance!!!

 

[rockola1971]

Need to know a little more information. Was it verified the oil was at or near the full mark when the engine "lost oil pressure". What is the oil pressure at when engine is cold and then warmed up also? How much mileage is on the engine?
If you heard audible tapping during your "loss of engine oil pressure" as indicated by the gauge then I would say that it was valid. GM engines just dont tolerate low oil pressure very well.
First thing I would do is go check your oil level now. It is quite possible your engine is ready for a new oil pump and that job is a little involved but not super difficult for most at home mechanics. Another possible scenario is the oil pickup Oring seal is leaking but those typically dont get better.

Pay close attention to excessive valvetrain noise (ticking), the engine isnt lying to you when it is doing this, there is a problem. But dont confuse valvetrain ticking with piston slap which is very common on this engine family, especially at cold startup and it is completely normal and harmless.

 

[strutaeng]

First thing to do is drain the oil and look for glittery material, but sounds like you already did that? If you have that, your bearings are gone and an oil pump is most likely is not going to do anything.

Not sure what your instrument cluster oil pressure is reading now, but you need to check with a mechanical guage if it's low.

Then go from there.

 

[Easiski]

Thankyou. The oil is fine, looks clear etc. When we changed the oil there was no metal residue, just gunk! I'm pretty careful to check all levels regularly (being old!) I've spoken to a specialist mechanic about 100Kms from me, and he did suggest that the oil pickup tube might be blocked or full of gunk, however it would seem sensible to change the oil pump now. Engine has done 346K Kms, so a high mileage in it's 24 years. It's a Canadian car, so the oil pressure guage is odd (not 40-60 etc. as I'm used to), but if it's the same positions on the guage, then it's about 30-40 on tickover when warm, and up to just about 60 at 2000 rpm. I haven't had any more ticking since, but I haven't done a long, fast journey either! 22nd Sept I'm going to my last show of the season which is about 2.5 hours away, so fingers crossed for that. The specialist mechanic doesn't like to use parts already bought so I'm waiting to hear from him and fingers crossed!
I really appreciate your replies.

 

[Easiski]

Need to know a little more information. Was it verified the oil was at or near the full mark when the engine "lost oil pressure". What is the oil pressure at when engine is cold and then warmed up also? How much mileage is on the engine?
If you heard audible tapping during your "loss of engine oil pressure" as indicated by the gauge then I would say that it was valid. GM engines just dont tolerate low oil pressure very well.
First thing I would do is go check your oil level now. It is quite possible your engine is ready for a new oil pump and that job is a little involved but not super difficult for most at home mechanics. Another possible scenario is the oil pickup Oring seal is leaking but those typically dont get better.

Pay close attention to excessive valvetrain noise (ticking), the engine isnt lying to you when it is doing this, there is a problem. But dont confuse valvetrain ticking with piston slap which is very common on this engine family, especially at cold startup and it is completely normal and harmless.

The noise is only when hot on long journeys. Hoping the specialist can fix it, and he'll check all possibilities, also change timing chain..

 

[rockola1971]

Thankyou. The oil is fine, looks clear etc. When we changed the oil there was no metal residue, just gunk! I'm pretty careful to check all levels regularly (being old!) I've spoken to a specialist mechanic about 100Kms from me, and he did suggest that the oil pickup tube might be blocked or full of gunk, however it would seem sensible to change the oil pump now. Engine has done 346K Kms, so a high mileage in it's 24 years. It's a Canadian car, so the oil pressure guage is odd (not 40-60 etc. as I'm used to), but if it's the same positions on the guage, then it's about 30-40 on tickover when warm, and up to just about 60 at 2000 rpm. I haven't had any more ticking since, but I haven't done a long, fast journey either! 22nd Sept I'm going to my last show of the season which is about 2.5 hours away, so fingers crossed for that. The specialist mechanic doesn't like to use parts already bought so I'm waiting to hear from him and fingers crossed!
I really appreciate your replies.

215K is uncommon for a 5.3L to need a new oil pump but certainly not impossible. Its possible the oil pickup tube got some sludge and was temporarily blocked and the problem you had fits that cause. I have a couple 5.3L's in (2) 2003 Tahoes and a 6.0L in a 05 Yukon Denali. Tahoes are close 300k and the Yukon over 300K. All are on original oil pump. Your oil pressures mentioned cold/hot are well within spec and healthy numbers.
Of course your mechanic doesnt want you supplying parts, he cant mark the cost of those up.

 

[Marky Dissod]

Change the oil as often as you can afford to - every 4500km should not be out of the question.
If you can find Valvoline Restore & Protect motor oil, it purports to clean things up inside the engine SLOWLY,
which may be exactly what you need.

Most motor oil additives are mixed blessings / tradeoffs at best.
Problem is people resort to those AFTER maintenance has already been neglected for too long.

Also, use PCV Valve 12572717.

 

[Easiski]

Thank you all for your help. The specialist has now said he can do it 2nd week of October, so I'm expecting a big bill, but he knows his stuff. It just seems sensible to do it now (timing chain too). As an old lady (72) who lives half way up a mountain and NEEDS the car daily, especially in winter, I'll feel a lot happier if he gives Yuki a clean bill of health, even if it costs 2 months pension!
I do appreciate that it might not be necessary, but after the changes it definitely won't, and I'll rest a lot easier.
I rally appreciate all of you.