Low oil pressure at idle, pulling my hair out, looking for any and all options.

[j91z28d1]

that front plate shouldn't be reused, it's cheap and if it leaks will kill oil pressure. I don't think there's anyways to see cam bearings with the cam in the block still.

if you're willing to pull the cam and inspect it's worth it. but I don't believe you can change them in the truck. they all look bad thou. Google ls cam bearing and welcome to the rabbit hole lol.

yours seems excessive. did you measure the bearings, main and rod yourself? cause that is a big drop.

 

[Geotrash]

New valley o-rings, very specific to order btw.

Brand new AC Delco oil pan which included that valve.

Felpro gasket kit included a new barbell which was installed.


Spoke to a could LS builders today, sounds like cam retainer plate can get worn and cause issues, even if only .001" out of spec. Always plug the relief valve, and triple check the barbell on place. Lastly check the cam bearings as much as possible with oil pan off.


SOOOO, we are going to pull motor back out.


Pass motor mount is shot, already did the H2 driver side upgrade but had a clunk and Revere power brake shows bad mount.

Only way to replace barbell if needed minus pulling trans, transfer case.

Easier to pull oil pan.

Easier to pull cam while out to inspect bearings, found a cheat with 5/16 solid rod to keep lifters in place.

Gotta pull exhaust manifolds, were just out so easy pull for mount.

Still same fluids dropped/wasted.

Annnnnnd just no more chances, especially with all new VVT parts already installed to no avail.

Gotta be a bigger internal bleeding problem, oil is leaking out and pump isn't starved. Dropping almost 50# of oil pressure once hot is insane.

Anyone else have any info??? Everything has been replaced minus the cam retainer plate.

Well that sucks. Sorry you have to pull it again.

While you have it out, I would plug those towers. Lingenfelter makes a kit for it that uses large rivets, or you can get a tap-in set from AMS Racing. I think Texas Speed sells a set as well. I've read of people still having oil pressure problems after replacing the o-rings, but having them still turn out to be the root cause.

Also, the 5/16" wooden dowel trick works great for holding the lifters in place. I cut mine to 24", which was perfect.

 

[Geotrash]

if you're willing to pull the cam and inspect it's worth it. but I don't believe you can change them in the truck.

You can change 4 of the 5, and the 5th one is almost never the problem, apparently. But you do have to pull the fans, radiator and transmission cooler out to get in there with the cam bearing puller. Of course, if you're pulling the cam, they're gonna be out already anyway. Gotta pull the oil pan too.

100% agree with you on that cam plate. Forgot about that one. That seal is a big source of oil pressure bleed-off.

 

[swathdiver]

high pressure/volume melling oil pump,

Which oil pump?

 

[kruznlow69]

Which oil pump?

We used a Melling 10355HV with standard spring.

 

[kruznlow69]

Update. We pulled motor yesterday. Found a couple things but sadly, all for nothing.

Backing up. When we pulled pan and timing cover last weekend, we swapped in
New Melling 10355HV High Volume/Pressure oil pump.
New GM VVT sprocket
New Melling solonoid valve
New GM Timing cover magnet
New pickup o-ring
Another reseal

Started up, hit almost 80PSI cold, then dwindles down to 5psi at operating temp, will drive but soon sets P0011 code and stabilitrack and will die and not restart.

Again, new engine built last year, installed a few months ago, less than 2000 miles. Was honed to 4.070, new DSS forged Pistons/moly rings, all new rockers, pushrods, lifters, trays. Polished cam, new cam bearings installed by engine machinist.

We found wrong valley cover gasket, but worked, and cam thrust plate had weird indents in the gasket. New gaskets again, new cam plate, pulled all rod caps and a couple main bearings to inspect, all are good. New barbell and rear cover gasket.

Cam bearings didn't appear to walk and upper 3nd looked good so we didn't pull it after finding the wrong valley gasket and maybe damaged cam plate gasket. We plugged the oil pan relief valve also.

We are losing our minds. 75psi swing in oil pressure... Gotta be bleeding out internally but can't see anything. Can the VVT be bad and dump oil electronically once warm?

 

[donjetman]

Put "plugs" in the AFM towers.

 

[j91z28d1]

I had to read back thru the thread. there's like 3 guys with the same issues?

wow that's weird.

so did any of the other guys fix there's? and one added Lucas Oil stabilizer and it made the whole truck run badly?


I'm so confused haha

 

[swathdiver]

One of the commonalities I see is that they are all using the 10355 pump (this and other threads across the internet) instead of the M365. It should not matter but it seems to.

What about that pressure relief valve in the pan? Anyone replace that with a plug and still have pressure issues?

 

[j91z28d1]

I had to Google those numbers. both are standard volume? just high pressure vs standard pressure.

huh. one of those web series on oiling did mention vvt take more oil volume than afm. I don't know that matters here as it seems some have non vvt cams and none have afm