Depending on the yr model of the LS, another source of oil pressure loss is the VLOM (valley cover) under the intake manifold. There are towers cast into the block that carry oil pressure to the VLOM that are prone to leak with age.
Chevy LS engine oil pickup O ring replacement on 4x4 trucks
- Thread starter Snagglefoot
- Start date
So the VLOM ( valve lifter oil manifold ) is a feature that comes with engines with AFM, correct? The issue probably needs its own thread. Is it very common?
Last edited:
- Joined
- Oct 26, 2022
- Messages
- 40
If the rear cover is leaking there’s a good chance that it will leak worse afterwards, when removing the pan you take the torque off those rear bolts going into the cover and when torquing them down on reassembly it will shift the cover ever so slightly because it’s not exactly lined up where it originally was causing it to leak worse.
I guess thats possible for a lateral leak, but it’s the oil pan gasket that provides the seal at the bottom of the plate.
- Joined
- Oct 26, 2022
- Messages
- 40
I know what the cover looks like, I’m not saying that the oil pan/rear cover seal is going to leak. The gasket for the cover where it seals to the block will leak, it’s not uncommon for them to leak anyways regardless of changing the oil pan seal or not.
Its been my experience that the LS rear main seal cover doesn't budge when the oil pan is removed and re-installed.
The 2 long oil pan bolts that screw into the rear cover are only torqued to 106 inch #s. There are 12 bolts holding the rear main cover in place.
I'll be dropping and reinstalling my 07 Denalis 6.2L oil pan again soon.
Here's a YT vid on how to do the o-ring without removing the oil pan:
The 2 long oil pan bolts that screw into the rear cover are only torqued to 106 inch #s. There are 12 bolts holding the rear main cover in place.
I'll be dropping and reinstalling my 07 Denalis 6.2L oil pan again soon.
Here's a YT vid on how to do the o-ring without removing the oil pan:
Got’er done. I rented a hoist in a shop and changed the O ring and pan gasket, as well as the gasket on the oil cooler line block. The oil pressure jumps to 40 psi immediately up startup.
Here are some picks. New O ring, old O ring and my Burb on the hoist.
Here are some picks. New O ring, old O ring and my Burb on the hoist.
Last edited:
I found if you watched the video in the original post, there were a few difference with my 2008 Burb. Mine didn’t have a oil level sensor clip to disconnect. It was a simple bolt through a metal to metal flat contact. Mine was a 6.0 but with very little difference. I did have to drop the axle a few inches, just like the video. You don’t get a reprieve just because it’s a 3/4 ton. I found you really do need a pole jack to get the diff back in position. Expect to make up a 10” long 1/2 extension and universal joint to grab one of the nuts that is used to bolt the diff to the frame.
Last edited:
Here is the bottom of the engine with the oil pan removed. You can see the dipstick that would be extending down into the sump. ( it’s a sideview, so it looks really thin.) I would remove it first next time.
This is an interesting shot to me. The engine side of the flexplate was not oily. Not sure if that means the main oil seal was not leaking.
After 260,0 miles there was a thin layer of sluge on the bottom of the pan. I pulled the baffle and cleaned it out.
Last edited:
This is the pan before cleaning up. The gasket original gasket is still on it. There are two rivets to drill out, shown with red circles.
Last edited:
BrendanC
$100 site donor 2024
i sincerely hope you used a ACDELCO oil pan gasket. if the leak isn’t solved, it will be the rear cover gasket.
Yes. AC Delco. So was the O ring.
Last edited:
The O-ring is at the front of the engine between the pickup tube and the oil pump. The screw holding the small flange squeezing the O-ring is shown.
While you are under there, it is a good time to check for transfer case pump rub on these. Right rear upper corner of the transfer case.
This 2008 was one of the first models using the Magna Power Transfer Case. The models prior to this were the ones with pump rub issue AFAIK. .
Yeah just more brilliant design work. Gotta like modern automotive engineering now. I'm just surprised they didn't figure out how to use a belt drive oil pump on those engines.
BrendanC
$100 site donor 2024
don’t get where you’re going here. OP got 260k miles out of that O-ring. i had 210k when i did mine.
only things my engine has required is a water pump at 195k, pickup O-ring at 210k and oil cooler lines at 234k.
I have a 2012 LS3 in a Corvette GS that from new, cold oil pressure is about 45 and hot idle oil pressure drops to about 23 psi at hot idle. This is the non-dry sump set up. Been like this since new, probably normal as the hot idle oil pressure is with the RPM’s around 550 in drive. While driving the oil pressure is about 35 ish.
Running Amsoil SS 5w-30. Slightly better oil pressure than when I was running Mobil1 5w-30.
The oil pressure in my 2003 LS6 runs both numbers about 10 psi higher. The ls6 also idles at 800 rpm.
Running Amsoil SS 5w-30. Slightly better oil pressure than when I was running Mobil1 5w-30.
The oil pressure in my 2003 LS6 runs both numbers about 10 psi higher. The ls6 also idles at 800 rpm.
Last edited:
