New Engine...Low Oil Pressure

[GMperformance03]

And the nightmare continues. After deciding to have the motor rebuilt in my 2007 Yukon Denali (6.2) I am dealing with an issue that has not been able to be solved so far.

The shop I paid to remove and rebuild the motor has taken the motor out several times since the original rebuild. The problem is when engine gets to operating temp the oil pressure only stays around 8-10 PSI. Seems very low for a supposed rebuilt engine. The rebuilder called me last week and told me it was fixed (wrong cam bearings installed) so I drove 4 hours north to pick it up. After driving about 15 miles I noticed the oil pressure dropping at low RPM’s and check engine light came on. The truck seems to run fine with the exception of low oil pressure at operating temps under lower RPM’s. Any idea on what the issue could be?

$4,100.00 later and I still dealing with this headache. Any help or advice would be appreciated. I do need to manually test the oil pressure to confirm the problem. Do the in dash gauges ever malfunction or give false readings or is that not real common?

Is this safe to drive given the apparent low oil pressure readings?

 

[GMperformance03]

Let me expand...the low oil pressure is typically at idle and low RPM situations. Typical driving conditions usual oil pressure stays between 30 & 40 PSI.

 

[Tonyrodz]

Whatever the issue is let the shop figure it out, especially for $4100. If you mess with it they might say YOU did something, and now it's not warranted any more. Let them figure it out, especially since they rebuilt it and you've paid them. Just my opinion.

 

[drakon543]

^^second tonys comment
also since its gone on for a while and thats a chunk of change. id start getting aggressive with them that they either figure it out or give you back a large chunk of that money so you can pay a better shop to figure out what they did wrong.

 

[Tonyrodz]

^^second tonys comment
also since its gone on for a while and thats a chunk of change. id start getting aggressive with them that they either figure it out or give you back a large chunk of that money so you can pay a better shop to figure out what they did wrong.

Agreed too. I think they're jerking you around.

 

[Kraig]

How complete was this rebuild?

 

[dnt1010]

Sounds like a oil pump issue (possibly the pickup tube oring) from the description. Do not drive your truck with low oil pressure take it back and have them fix their mistake.

 

[petethepug]

Why don’t you do the overfill the oil in the crankcase trick to see if the o ring on the pick up tube is compromised. Don’t have the thread handy but it’s deff something that can be checked and immediately reversed.

Until the thread is posted ... it describes overfilling w/ oil at idle, no drive truck when overfilled, savvy?


Sent from my iPhone using Tapatalk

 

[BG1988]

Let me expand...the low oil pressure is typically at idle and low RPM situations. Typical driving conditions usual oil pressure stays between 30 & 40 PSI.

mine is about 50-70PSI under typical driving conditions

Hybrid Vortec 6000

 

[swathdiver]

mine is about 50-70PSI under typical driving conditions

Hybrid Vortec 6000

The aluminum V8s run lower oil pressures than that. The bypass is set for the 30s.

And the nightmare continues. After deciding to have the motor rebuilt in my 2007 Yukon Denali (6.2) I am dealing with an issue that has not been able to be solved so far.

The shop I paid to remove and rebuild the motor has taken the motor out several times since the original rebuild. The problem is when engine gets to operating temp the oil pressure only stays around 8-10 PSI. Seems very low for a supposed rebuilt engine. The rebuilder called me last week and told me it was fixed (wrong cam bearings installed) so I drove 4 hours north to pick it up. After driving about 15 miles I noticed the oil pressure dropping at low RPM’s and check engine light came on. The truck seems to run fine with the exception of low oil pressure at operating temps under lower RPM’s. Any idea on what the issue could be?

$4,100.00 later and I still dealing with this headache. Any help or advice would be appreciated. I do need to manually test the oil pressure to confirm the problem. Do the in dash gauges ever malfunction or give false readings or is that not real common?

Is this safe to drive given the apparent low oil pressure readings?

Yes, gauges and sensors can be faulty. The screen under the sensor may have become clogged or any number of other problems may have arisen during assembly. From not using the right parts to not having cleaned the motor properly prior to assembly. Even the dumbell in back needs to be put in right along with the pick up tube o-ring and on and on.

If it's under warranty, it's safe to drive!

 

[GMperformance03]

Just to update...

Supposedly a cam bearing was installed incorrectly causing the low oil pressure issue. I will be picking the Yukon up tomorrow to find out for sure.

The rebuild consisted of (actual ad below):

Block is bored .20 over. New pistons, rings, cam, cam bearings, main bearings, rod bearings, lifters, hv/hp melling oil pump, seals and gaskets, valves, springs, etc... Block gets decked, line honed and heads are checked and resurfaced. Nothing is forgotten or skipped.

After driving Yukon tomorrow I will update this thread.

Thanks for all the great replies.

 

[Rocket Man]

Awesome. Not forgotten, just done wrong so you go through hell.

 

[GMperformance03]

So the idiot engine shop out of western MI did not fix the problem. I still have low oil pressure (15-20 psi) hot idle, & 40 psi idle at 1,500 rpms.

I will withhold their name until this situation is fixed and/or if I need to get legal representation. Their solution now is to change the block to a cast iron block and their claim is that the aluminum block is defective. Do they even make a 6.2 liter cast iron block?

This is the third engine that they’ve installed and the fifth time the motor has been removed and reinstalled. I have spent almost $1k on rental car expenses in addition to the multiple times I’ve had to drive from Indiana to Michigan.

 

[Rocket Man]

So the idiot engine shop out of western MI did not fix the problem. I still have low oil pressure (15-20 psi) hot idle, & 40 psi idle at 1,500 rpms.

I will withhold their name until this situation is fixed and/or if I need to get legal representation. Their solution now is to change the block to a cast iron block and their claim is that the aluminum block is defective. Do they even make a 6.2 liter cast iron block?

This is the third engine that they’ve installed and the fifth time the motor has been removed and reinstalled. I have spent almost $1k on rental car expenses in addition to the multiple times I’ve had to drive from Indiana to Michigan.

View attachment 225838

Wait...three different engines? Three different blocks or are they rebuilding the same block? I’m confused.

 

[GMperformance03]

Rebuilding the same block.

 

[swathdiver]

Rebuilding the same block.

This is terrible Greg and am sorry you're going through it. All the 6.2 blocks are aluminum. The 6.0 are made in both materials.

Engine building 101 was to have the block checked for cracks when it was cleaned. We used to have the blocks and the heads magnafluxed or sonic tested before we did anything to them lest money be wasted.

Time for a GM Performance crate motor, L9H or L94?

 

[GMperformance03]

Anyone have any recommendations on reputable machine shop or engine builders at reasonable prices?

I really am trying to stay away from a 6k-8k engine cost, other than Jasper. Thanks

 

[Wambliokiye]

Just to update...

Supposedly a cam bearing was installed incorrectly causing the low oil pressure issue. I will be picking the Yukon up tomorrow to find out for sure.

The rebuild consisted of (actual ad below):

Block is bored .20 over. New pistons, rings, cam, cam bearings, main bearings, rod bearings, lifters, hv/hp melling oil pump, seals and gaskets, valves, springs, etc... Block gets decked, line honed and heads are checked and resurfaced. Nothing is forgotten or skipped.

After driving Yukon tomorrow I will update this thread.

Thanks for all the great replies.

6.2?

 

[GMperformance03]

6.2?

Yes. 2007 6.2

 

[swathdiver]

Anyone have any recommendations on reputable machine shop or engine builders at reasonable prices?

I really am trying to stay away from a 6k-8k engine cost, other than Jasper. Thanks

https://www.gmperformancemotor.com/parts/19329865.html

New Short Block, 3 Year, 100K Mile Warranty. You can often find used engines locally in totalled vehicles, still running, so you can verify that they're good. Ebay has a bunch for under $3K with free shipping.

How are you with turning wrenches?