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2008 GMC Envoy Denali

Jaryd said:
Never seen a oil pan like that. Crazy what the car manufacturers come up with to make things work.

By the looks of them bearings I’m willing to bet the PO herd a noise and just kept driving around until the noise finally stopped one day. Looks like the PO was one of them people who bought it and never checked or changed the oil in it. Just kept driving wondering what is that noise I’m hearing.
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I forgot to finish my thought. They were defintely driving around for a while with the rods hammering and either ignoring it or listening to the stereo too loud. I guess when your parents give you a vehicle you can do that.....I wouldn’t know what that’s like.
 
Will L. said:
Wow those cylinders do not look good- that dude got way hot.
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I wondered if that’s what it was. What’s weird is those were #6&8 and #1&2 were the ones that seized. I guess it’s probably that those are the last ones to get cooled so they would get the hottest.
 
Picked up an LQ4 short block tonight. It’s a 2003 6.0 with about 120,000 miles on it. It’s already partially torn down. I was planning on reusing the pistons, but since they’ve been removed and look kind of scuffed I’ll probably replace them. Or maybe they just need to be coated? I’ll see what Chris thinks. I wanted the LQ4 because it has dished pistons. With the heads I have it should be around 10:1 compression which should be able to run on 87 octane with a good tune.

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Disassembled the 6.0 this evening. Tomorrow I will do some measuring and see what I have for sure.

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One conundrum I have is the crank. The PO removed the rods and pistons and this allowed the rod journals to start to rust. I’m not sure if this will clean up with a polish or if they will need to be ground.

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Also since it’s a 24 tooth reluctor wheel I’m going to have to buy a 58 tooth wheel and have that installed. So that’s X amount of money that crank needs invested into it. The other option is the crank that came out of the 5.3. It has the correct reluctor wheel but that rod journal is toast. Will it clean up with a regrind? Did the heat damage it beyond repair? Don’t know. So that could potentially need Y amount of dollars invested. So should I just get another crank period? I’ve done some looking locally and nothing is leaping out at the moment, but I’ll keep looking.

Also there is the rod and piston situation to look at. After digging them out and looking at them tonight, they might be ok after all. They don’t look scuffed, the carbon was just wiped off there. Tomorrow I’ll start really inspecting them and see what I have there. They’re press-fit, so if I need new pistons I need to invest in pistons AND their installation. The Gen 4 pistons are full floating so I can install those myself, but only 6 of the Gen 4 rods from the 5.3 are good so I need to find 2 more of those plus buy pistons. So I need to start writing things down and make the plan that makes the most sense....

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The 03 lq4 is the undesireable bottom end. They used the weak rods stock. You already know about the 24x vs 58x. You can buy the lingenfelter converter box to deal with that, but I would get a crank with a 58x balanced for the lq9 rods if it was mine. And 10:1 for an LS is low compression. The lq9 is a bit over 11:1 and runs fine on 87 octane. The flat top pistons actually have better quench height which helps resist pre-ignition along with the 317 head runner design. For naturally aspirated the lq9 is a better option, the lq4 is better suited for boost.

As to your 5.3l aluminum block, they're not that desireable except for street rods and other applications where weight matters. They're known to be fairly weak and don't take well to boost.
 
THEFERMANATOR said:
The 03 lq4 is the undesireable bottom end. They used the weak rods stock. You already know about the 24x vs 58x. You can buy the lingenfelter converter box to deal with that, but I would get a crank with a 58x balanced for the lq9 rods if it was mine. And 10:1 for an LS is low compression. The lq9 is a bit over 11:1 and runs fine on 87 octane. The flat top pistons actually have better quench height which helps resist pre-ignition along with the 317 head runner design. For naturally aspirated the lq9 is a better option, the lq4 is better suited for boost.

As to your 5.3l aluminum block, they're not that desireable except for street rods and other applications where weight matters. They're known to be fairly weak and don't take well to boost.
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I’m pretty new to the LS game, but I have been reading quite a bit for a month or so on these. What you say is true, but that is more for people going for bigger performance than I am. I’m aiming for a torquey daily driver that will still run on regular gas - that’s why I was looking for the LQ4 bottom end with the dished pistons. The Gen 3 rods should be fine for my anticipated power level (450 - MAYBE 500hp at the flywheel). I tried calling Brian Tooley Racing for a cam recommendation today but got voicemail....when I do get through, compression is one of the things I’m going to ask on a recommendation for so I’m going to leave all piston decisions until after I have that conversation. I feel best changing the reluctor wheel and using all factory electronics rather than add an additional widget into the mix. Same goes for the knock sensors: I’m going to move them into unused holes in the side of the block so they should function the same as the Gen 4 and use the factory harness.
 
THEFERMANATOR said:
The 03 lq4 is the undesireable bottom end. They used the weak rods stock. You already know about the 24x vs 58x. You can buy the lingenfelter converter box to deal with that, but I would get a crank with a 58x balanced for the lq9 rods if it was mine. And 10:1 for an LS is low compression. The lq9 is a bit over 11:1 and runs fine on 87 octane. The flat top pistons actually have better quench height which helps resist pre-ignition along with the 317 head runner design. For naturally aspirated the lq9 is a better option, the lq4 is better suited for boost.

As to your 5.3l aluminum block, they're not that desireable except for street rods and other applications where weight matters. They're known to be fairly weak and don't take well to boost.
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I was just thinking about this some more. You bring up a good point regarding the LQ9 pistons - if I have to go the route of new pistons, I may as well go LQ9 and get a cheap set of 317 heads. About the same compression ration but more efficient quench. I’ll have to get 2 new Gen 4 rods, but that’s doable.
 
Lq4's LOVE boost. And FYI, SCAT makes a set of factory weight drop in rods for the light rods for around $250-275 a set last I checked. There's no way I would chance it for under $300 to get a set you don't have to worry about.

Just checked, JEG'S sells a new crank with the 58x reluctor for $320.99.
 
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Today I did some kind of preventive work so I don’t end up having to do a restoration to this one like I’m having to do to the Tahoe. I got the first two steps of the 3-step KBS Rust Seal kit done.

First thing I did was 3 rounds of their Klean degreaser with a wire brush.

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After that I wire wheeled the rust and any other flat surface I could get to to rough the surface up for the paint. After that I did another spray with the degreaser and then a rinse with clean water.

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After that I dried the frame with compressed air to get ready for step 2. Step 2 is the rust conversion Rust Blast. I kept that wet on the frame for about an hour so it could really work on some of the spots I couldn’t reach with a wire wheel. After the soak I rinsed it all off with clean water and blew it dry.

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Tomorrow I’ll put 2 coats of Satin Black Rust Seal on the frame.
 
Tonight I did the trunnion upgrade to the rocker arms. Apparently the factory needle bearings in the rockers can fail which not only means a rocker isn’t doing its job properly, but then you also have tiny needles floating around in your engine. I bought the kit from Brian Tooley Racing.

It has nice instructions.

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Here is an exploded view of a stock rocker after disassembly.

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And here it is with the new parts instead.

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It took a little over an hour for me to do all 16 rockers. Here’s a finished rocker plus some extras. It was nice to see they provided an extra bearing and a couple extra clips so you could make a mistake without having to order more parts. You can also see the new bolts and a 12 point socket for the bolts included in the kit. Pretty nice stuff.

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