Gen III/VI Small Block Oil Consumption & Oil Pressure Issues

ktmlew · October 25, 2015

Been researching this topic and found a document that mentions changing LH valve cover due to PCV drain hole being incorrectly positioned. Also rec'd installing a shield on pressure regulater in oil pan if pan removed to keep oil spray off bottom of pistons. Aware of issues with oil pump pick-up o-ring and with lifter screen getting fouled with debris. I am dealing with 2001-2011 4.8/5.3/6.0 in vans/pickups so I assume no AFM?

Have a couple with obvious oil pressure issues. I assume checking the pick-up o-ring and lifter screen are the first steps? Assuming oil pressure is consistent at lower filter port and at sending unit. If the oil pressure concern is repaired then address the possibility of rings being carboned/sludged up? What chemicals are you guys using to "flush" the ring grooves. The injector flush fluid 2.5 hr soak working?

sneakypete · October 25, 2015

big difference between a gen3 and gen4 ls engine. can't say gen3's have oil consumption issues unless customer has neglected it. gen4 is another story as you've found out. first step would be oil pressure check at filter and at oil sending unit. will need an adapter for both to do it properly. what oil filters are you using. that makes a huge difference. if you have a low oil pressure concern you can have the pickup tube oring causing a leak. also cam bearings can be worn causing an internal leak. usually this will be accompanied with high mileage and vvt dtc's, but not always. have also had oil pump issues but not too many.

as for oil consumption, there was an update to the left valve cover and afm shield upgrade; which you've already researched. but you will probably still find oil consumption after doing that. I don't know how many piston rings I've found lined up. 8 piston assemblies and new rings will fix your consumption issues. there was an update for these.

you can try a top engine cleaner for the piston ring clean up. I recommend gm's top engine cleaner. introduce it through a central vacuum line and let it sit for aprox 1 hr to 1.5 hrs any longer and it will start hardening up.

ktmlew · November 5, 2015

2010 4.8 oil pressure with Tech 2----29psi @ idle---48psi @ 2500. Have a fairly solid knock at higher RPM, doesn't sound like bottom end to me. Either lifter or cam bearing issues? Any options on those crazy expensive adapters to check pressure with gauges at both ports?

Using cheap ProMotive Advance filters. They were made by Purolator. Advance bought Carquest so now getting Carquest boxed filter. Who knows who makes it?

Have a couple others that sound like they have no oil pressure. Will be checking them out in next couple days/weeks. Likely already killed IMO. Have a couple others that the oil "light" is on but pressure reads good at gauge? My problem is getting them to leave the vans with me. They want to shoot through the building for a 20 minute oil change...

I assume you change all 16 lifters & install new oil manifold? Check oil pump o-ring, install AFM valve shield, replace lifter filter screen at minimum?

Bruce Amacker · November 5, 2015

Consider an oil analysis to see if something is wearing abnormally inside, Napa/Wix PN 4077 or 24077 is $13 + $1.50 shipping. It gives you levels of about 40 things in the oil and great clues if something is wearing out.

Also, don't forget the possibility of carbon on the piston hitting the head.....

:grin:

Fredsvt · November 5, 2015

Think 6.0 lifters. They tend to either lose the needles or the roller just doesn't. Then you know what happens.

Do you have any AFM engines there yet?

All LS series can have piston slap that make a Ford 5.4 seem quiet. They use very, very short skirt pistons.

ktmlew · November 6, 2015

The one above does sound like piston slap. My previous experience with piston slap was more pronounced on a cold engine. According to the info i have most of the vans didn't use AFM?

amailloux · November 6, 2015

I believe that engine has no dod and also no screen under the oil pressure sensor. you have good oil pressure. when the lifters or

cam fail, they make a pronounced squeak, squeak at idle. This engine used flat top pistons and can build carbon as well. the 5.3

uses dished pistons. The GM green soap top engine cleaner is not nearly as good as the old stuff and has not been good at unsticking rings. I would try your favorite induction cleaner and procedure for carbon and the let her rip.

sneakypete · November 7, 2015

cam bearings never made noise. the only times I had issues with cam bearings was on vvt issues usually. the #2 bearing feeds oil to the vvt assembly. knock noise as stated could be carbon build up and I've also seen wrist pin issues but only on abused engines. think poor maintenance. not a normal concern but have seen it.

I picked up both adapters off ebay for a good price. there is a kit I've used for the oil filter adapter. I'll get the kit name and number on Monday when I return to work. but for the top adapter you need to buy the kent moore one.

you need way better oil filters then that. sorry to say. what type of oil you using. I'd be using dexos spec oil.

if I have an afm issue or cam failure; it would be cam and all lifter, vlom assembly, replace the oring at the pickup, afm shield (if not already installed), oil pressure screen and clean out oil pan. since your that far I would be putting in an oil pump as well. now the thing is the price to do only the lifters and cam is just slightly cheaper then putting in an engine. something to think about. not sure how your fleet deals with that.

almost certain the vans don't have the displacement on demand engines. they usually do have vvt though.

ktmlew · November 8, 2015

I believe that engine has no dod and also no screen under the oil pressure sensor. you have good oil pressure. when the lifters or

cam fail, they make a pronounced squeak, squeak at idle. This engine used flat top pistons and can build carbon as well. the 5.3

uses dished pistons. The GM green soap top engine cleaner is not nearly as good as the old stuff and has not been good at unsticking rings. I would try your favorite induction cleaner and procedure for carbon and the let her rip.

How do you rec doing an induction service? Only ones i've done last 10 years were with "fogger" inserted into the TB using BG Products. What about Seafoam? Or is the GM procedure the bast way. Pull plugs and do the soak?

ktmlew · November 8, 2015

This should work at the sensor port.

http://www.amazon.com/gp/product/B015NFNC10?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

Now just need an adapter for the filter area.

amailloux · November 15, 2015

I have been using the green top engine cleaner for now. It has been hard for me to track, but 2 have required pistons, 2 other are not burning oil at the moment, and the other dozen or so were not regular customers so who knows.

ktmlew · January 5, 2016

Finally dug into one of these for oil pressure issue. 2007 4.8. Had been chasing a slow coolant leak...found it! Milkshake city. Was planning to replace the oil pump as had 25psi cold. Manager said go ahead and do the pump and lets see how far it goes...I don't have all the tools for these. Why have they quit putting dowel pins on timing covers? Stupid. Installed cover with bolts loose, installed damper...AFTER going to Fastenal and getting reamed for 32 bucks for a piece of threaded rod and 25 nuts...yes 25...assholes. Tightened cover after damper install to center/locate cover. I ordered a damper installer and seal butt plug last night. Won't have them till early next week. Started it right before I left. 50 psi. Better. I suspect porous head casting.

Fredsvt · January 6, 2016

Have you found any with cracked left cylinder heads yet? Just had 3 in the past week, all losing coolant with no external leaks. 2 Suburbans with 5.3 and one 08 G cutaway, 6.0, horrible coolant smell out of air filter box on the van.

Easy to find if it's been going on for a while, open throttle all the way and look inside the intake, if you see a big puddle of orange about midway down the intake, right where the pcv orifice hose goes, you'll find a nice long crack in the head on the left side.

Of course no one wants to spend that kind of money on a truck with 150k plus. So, they top off.