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Dear lord help!!

Hhittagd

New Member
Joined
Feb 9, 2020
Messages
7
Im sure im crossing more than one thread and i tend to ramble on from time to time so just bear with me. Been a lot of history digging in this Av but its coming to an end unless i can get a bearing on it.
Most of my problems kicked off lately on top of my recurring problem when i "accidently" went muddin over fathers day weekend. And yes it was definitely fun but definitely unintentional. Wont go too deep into unless sonebodys curious. All in a nut shell ive got a bad oil leak i have been fighting for over 2 years. 03 z71 with a 5.3 and about 224 on the dash. I got a lil stuck and buried my buddy (literally) all the way to the frame for about 4 hrs or so. After getting the Av back out i noticed immediately i needed sum service to say the least but he still carried me around and 2 days later still drove me 200 miles home dragging a trailer and my family. Only reason im saying this is i love my Av and its been good to me but its a money pit because i cant solve this problem and hoping the pros can help me save it.

Over the last 2 years i have done quite a bit of work and done it all myself chasing the oil leaks. Head gaskets a year ago, oil sending unit, knock sensors, front main seal, intake manifold. I have replaced the water pump also(not oil related). After my muddin trip i broke down the Av completely. New hub assembly, cross drill and slotted front rotors, brakes all around, new head gaskets, manifolds gaskets, ruthenium spark plugs, new fan clutch, new water pump...just about everything but a starter smh. Cranked it all up and no leaks! Happy as can be. Hit the highway and slammed all the way to 100mph. No leaks. Parked and let it run. No leaks. About 3 days later my dash says low oil pressure. Now my oil leak is back, heavy, and confusingly uniform. It has been located hidden at the back of the block until now. Now its leaking from under the valve covers on both sides at the 3rd cylinder from the front on each side. Has anyone seen or had this problem and have a solution. I cant keep up with this pace. Any additional info just asked. Also yes i torqued everything to specs, cleaned thorougly b4 hand, all are new gaskets, and yes heads torqued to ls1 specs for all 3 passes. Yes my horsepower seems effected but more intermittently, not constant. Thanks ahead of time. Ive never posted b4 so im hoping for good feedback. Sorry if i rambled too long
 
What's the oil level? Is it only low pressure or also low oil level? PCV valve replaced? Oil pump replaced? It sounds like an internal blockage of some sort.
 
Cracked engine block I would guess. And / Or head.
I would stop chasing and look into a engine swap.
The rest of the truck sounds good after all the work you have done.
 
You mentioned head gaskets twice.

Are you actually changing the head gaskets or the valve cover gaskets?

Did you replace the rear main seal and/or rear main seal plate during all of your repairs?
 
PICTURES please of where you say it is leaking

Because what you say with words is a new one.
 
What's the oil level? Is it only low pressure or also low oil level? PCV valve replaced? Oil pump replaced? It sounds like an internal blockage of some sort.
The dash says check oil level. The oil pressure gage does drop accordingly. You can physically see oil leakage present above the exhaust manifold right under the valve cover
 
You mentioned head gaskets twice.

Are you actually changing the head gaskets or the valve cover gaskets?

Did you replace the rear main seal and/or rear main seal plate during all of your repairs?
No. The first time head gaskets were replaced was necessary. Found the ring of death around the oil cap. 2nd time was just to hopefully eliminate all possible problems for the future. No rear seal has been touched(thank god). Chrcking inside the bell housing inspection plate it looks very nice and clean inside.
 
I cant figure out how to put in pics. I took pics but cant figure this part out
 
PICTURES please of where you say it is leaking

Because what you say with words is a new one.

I took pics but cant figure out how to upload. On checking while taking pics im noticing black assuming carbon residue also above the valve gasket. Further history on my Av, when i bought it a few yrs ago it still had 2 of 3 of the electrical parasitic draws and an exhaust problem. Previous owner said he had a hole in the muffler so instead of fixing or replacing it he cut the exhaust behind the cats. Could possibly the weight from the exhaust being suspended only by bolts on the manifold be causing this issue finally? Or would it turn into a larger but diff problem?
 
upload them to your FREE media album then post link.


as your membership grows (next step is Full member) the more permissions you get like easier to post pictures.


All in the name of spam protection
 
I cant figure out how to put in pics. I took pics but cant figure this part out

After you make a couple more posts, you will see the "Full Member" tag under your name.

Once you are a Full Member, you will see an "Insert Image" button on the toolbar when you are composing your new posts.

Pick the spot you want your picture to appear, click the Insert Image button and browse for your picture and insert.

Done.
 
No. The first time head gaskets were replaced was necessary. Found the ring of death around the oil cap. 2nd time was just to hopefully eliminate all possible problems for the future. No rear seal has been touched(thank god). Chrcking inside the bell housing inspection plate it looks very nice and clean inside.

A couple of things.

It has been my experience that popping off the observation port on the transmission bell housing does not always show oil leaks.

The engine oil is very thin and you will not see a huge sloppy, dirty oil leak.

When we were confirming the location of my bad oil leak, we popped off that cover and had a look.

It was a little damp, but no where near the amount of oil that compared to the oil that was ending up on the ground where the truck was parked.

I poured a bottle of Certified Auto Pro Oil and Fuel System UV Dye Leak Detection for Cars & Trucks into the crankcase and drove the truck around for a hundred miles or so.

We pulled the truck back into the bay and used a UV flashlight to pinpoint the source of the oil leak.

The entire inside of the bell housing was glowing in the UV light.

The thin engine oil gets slung all over the place in there and coats everything.

Eventually, the oil will settle toward the bottom of the bell housing where it will leak out onto the ground.

But, just looking up in there with a regular flashlight did not show much.

What we found was not only was the rear main seal itself leaking, but so was the seal for the entire rear main seal back plate.

I just purchased the rear main seal and rear main seal plate assembly and had the whole thing installed.

That UV dye will also confirm any other source of oil leaks on your engine.

I have reread your posts and you seem to indicate that you have confirmed to have located oil leaking from above the exhaust manifolds.

Typically, an oil leak at that location would point toward a bad gasket seal at the valve rocker arm covers.

I prefer to only use Fel-Pro valve rocker arm cover gasket kits for this repair.

Did you also replace the mounting screw grommets?

The torque spec for the valve rocker arm cover bolts is quite low at 106 lb in or about 8 lb ft.

Over torqueing these bolts can cause bad things to happen.

Pinched gaskets, distorted covers and certainly broken bolts or striped mounting holes.

When I broke one of my bolts, I found these bolts are not quickly available and I ended up having to rob one off of a junk engine at my mechanic's shop.

Just a couple of things to consider.
 
I'll chime in and say, you have 224k on the dash. All the work you have listed that you have done is very typical of Chevys ( or any vehicle really) with that mileage. You are a bit rough on it occasionally. That's what a truck is for. Don't get discouraged about continually putting money into fixing an older truck. A new one will cost you way more! If you are getting fed up chasing the problems yourself, it may be time to take it into a trusted tech. Let them fix it, and enjoy your truck. Sometimes, cool stuff sucks... sometimes.
 
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