Bertha - 08 GMC Yukon XL Denali

[nocooler]

So this is owned by a good friend of mine. It's had a low oil pressure at idle for quite some time and then started making some interesting noises. We both thought it had got a lifter and his normal mechanic shop said they'd change the engine for $6500 but other than that they wouldn't touch it.
The tear down went smooth - broke one exhaust manifold bolt off in the head and a manifold stud.

[nocooler]

Although I was surprised that everything looked good - until I found this.
The 6.2 has VVT but not DoD/AFM so it uses this style tensioner - and it broke. Luckily he only put 20 miles on it like this. The low oil pressure problem was due to a stuck oil pressure relief valve in the oil pan.

[nocooler]

Basically - I'm re-gasketing/sealing the engine. New oil pump, lifters, valve spring/seals, VVT cam phaser, timing chain, tensioner, and plugging the bypass in the oil pan.
Since I had it tore so far apart I decided to split the engine/trans and replace the rear main seal and the rear cover gasket just to make sure everything is fresh.
It's back together waiting for a valve spring tool to show up since the ls1 and ls3 style heads use different spacing for the rocker stands/valves.

[Steve Wood]

I had forgotten about this one.

It is amazing how frequently these things arise these days and one has to wonder if the shop was just smart enuf to know they did not know what they were doing, or if they just took the easy way out because they figured it was easier to replace the engine and make some serious money without perspiration.

He was lucky he knew you and it is getting fixed as well as being done correctly to head off future potential problems.  That is the second time in the last 15 years, that I have seen a stuck open bypass valve.

It's a lot of work to do some of this stuff but I find it way more satisfying to have figured it out.

good job!

[Just a Six?]

That's a big job & they're hard to work on with the truck so high up but looking good! More than I would want to tackle myself. Your buddy will have a great truck again. 

I got my 04 off a long lease & now has just under 200k miles almost all hiway so it runs good but lots of salt abuse means lots of rust too. I did repairs around the wheels this summer & then sprayed a few rattle cans of assorted black & I ended up using the Rust Check Gloss Black & gave it a little buff. Looks decent enough for me.
   

[nocooler]

Here is a picture of the oil pressure relief valve that I removed and plugged.
Steve - I was baffled when I tore it apart and initially didn't find anything. I was expecting a glitter bomb, and all I found was some plastic from the tensioner.
David - Size has been a problem, the engine is so far down in this body style that it makes it a bitch. Hell by the time I get the thing high enough to get under it, I can't even reach what I needed to work on anymore. If I could get the a/c condenser out of the way it would open things up, as I could remove the core support.

[Steve Wood]

Sometimes you get lucky...me, mostly not.

I took much of the stuff off my Miata to make it easy when my son came up and we pulled the diff carrier out to install a rebuilt diff in it.  I figured it would take about three hours to install the new diff and put it back together.  It took us a couple of hours to finish getting the diff separated from the power plant frame that locks the diff carrier into place with regard to the transmission.

Installing the replacement diff into the carrier was easy and getting the assembly back into the car and locked down was not too bad/hard.

Getting the half shafts to pop all way into the diff turned out to be a two day process that I won't bore you with.  Hopefully it now works right.  I cannot find out because when I went to move the Challenger to get the Miata out, the MSD Ready to Fail distributor that had about three hours or so run time on it, blew out the 50 amp fuse in the hot wire and messed up the relay-was showing a dead short.  Seems they have a worse reputation than the rest of their chinese crap they sell.  I am still waiting on stuff to come in so I can install a new distributor and I still have not been able to remove the blown fuse that is now welded into the maxi fuse holder which I guess I have to replace as well.

But that is another story altogether...I was going to buy a top side creeper for working on trucks, but never did.  I cannot stand up under a truck to work on it because 30 seconds later my sciatica is killing me so it's either lay on the floor or sit up under the truck and my four post lift does not leave much room to get to a lot of stuff under the truck...   I think old age really likes to piss me off.

[nocooler]

Top side creeper is going to be a must if I do another one of these. I’m tired of the damn milk crate sliding around the under my feet.
I’m ready to be done looking at this thing, and my body is ready to be done wrenching on it.

[Steve Wood]

My milkcrate skates around like it is on wheels, too

[nocooler]

It's 95% of the way done. I had a small snafu - a valve keeper escaped when I was changing the valve springs. I put it back together with a different pair of keepers on that valve from my stash. For the life of me, I can not find that damn keeper and it's pissing me off. I've been through all the pushrod holes and oil drain backs with magnets. I'm 98% sure it's not in the engine, my guess is it's in the chassis somewhere, but I'd feel better if I could find it. I may pull the starter tomorrow to see if it found its way there...

[Steve Wood]

That will drive you crazy if you don't find it

[nocooler]

Found it - I was just getting ready to take the exhaust manifold and starter back off to dig deeper for it.
I grabbed the o2 harness to unplug it and the keeper fell out and hit me in the chest. Woohoo - huge relief!

[Steve Wood]

I know it is!  I am glad you found it...hate to have to pull it all part.

[nocooler]

Just needs the intake installed, harness plugged in, alternator/belt installed then fluids. I need to install the front bumper cover and inner fender wells too.

[nocooler]

Fired up on the first try. No noises and normal oil pressure. It appears the thermostat seal might have not seated properly I have a drip from the thermostat housing, but other than that it's good.