Reprise's 2003 Sierra Build Project <name TBD>


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So, as we all get used to 'life under coronavirus', I've reconsidered having the rear axle noise diagnosed / fixed before beginning my long-planned (and long-promised!) build. Partially, it's because I'm now suspecting that the noise I'm hearing may be U-joint / driveshaft / pinion related, and that whichever it is, it's in 'early stages'. Might be misplaced optimism, but I'm sticking with it, for now.

Which means... this is now a perfect time to start the build, in earnest, since my personal mobility is being limited right now.
- This won't be a 'one-to-two day' project (although I'm sure some of you could do it in that time) -- so, if you're interested in following, you may want to 'subscribe', so that you'll be notified when I post something new / worthwhile.
- For the same reason, don't expect 'daily' updates.
- If you see I've done (or about to do) something 'wrong', don't be afraid to voice your concern. I intend to explain why I'm doing certain steps, as they come along. (but I'm also aware that my postings easily become longish, so striking that happy medium may be a challenge, at times!)

Here's a couple photos of our 'patient'...


This first one is how I 'got' the truck. 2003 Sierra 1500HD, with about 230K.
You'll note the C3 / Denali grille / turn signal housings / bumper cover (which is not flush due to the previous owner not using the special brackets required with that cover), along with the H2 rims / big-ass 315/70/16s.
The owner before him had a CB Radio in the truck (that's what those antennas behind the cab are for).
This truck spent the first half of its life in Texas, and there's almost no body rust / only surface rust on the frame. Lucky me.
Those bulging rear fender flares indicate that this truck has Quadrasteer. Thankfully, the previous owners didn't use this for towing boats, as the system is still operable. Incidentally, those flares are... fiberglass, meaning that they'll never rust, like the rear wheelwells normally do. The rest of the bed is steel (and it has a Line-X bedliner, which is in excellent shape, for a 17-year old truck. Lucky me, again.

Over the last several months, I've replaced most of the front suspension, tires / wheels, tailgate (which was dented), the rear axle (a 35-spline Dana 60 with kingpins), new rear hubs (which are like front hubs on a 4WD truck), caught the truck up on maintenance in various other areas, replaced the Flowmaster with a stock muffler / tailpipe, and gotten it to this point:


Yeah, those are Chevy center caps - sue me. LOL Tires are BFG 265/70/17s (highway tread; I tow with this truck, and don't leave pavement). Those are new headlamp / turn signal housings, and the OEM grille / bumper cover. Added a soft tonneau & nerf bars (you don't see the passenger one here, but it's there now)

The gap you see between hood / fender / grille is because I forgot to latch the hood before taking the pic (oops).
I also turned on the QSteer in this pic, to emphasize the 4WS, but you can't really tell, here (it moves a maximum of 14 degrees, so it's subtle). Oh well...
Yeah, it's dirty. Sue me again.

Drivetrain on this beast is an LQ4 6.0L and a 4L80E, to go along with that Dana 60 rear (which has a 4.10 gear). While my previous 1500HD had a lot of torque, compared to the 5.3L Envoy XL I was towing with, this motor is even stronger. Which makes me think it's got a tune, at the very least, and maybe some aftermarket parts. We're going to find out, as I plan to replace / upgrade the following:

- Heads (with new rebuilt 317s)
- Tow cam / lifters / springs / timing set
- Oil pump (not 100% sure on this, yet)
- Intake (and I may relocate the knock sensors to the Gen IV locations on the side of the block)
- Items which get touched on the way to the cam (like the water pump, hoses, etc.
- Tuning / dyno
- Couple addn'l appearance items

All of the above will be on top of the stock (?) bottom end, which has good compression / power / oil pressure, and doesn't burn / leak oil (which is why I may forgo the oil pump upgrade). I also had Blackstone do an oil analysis to make sure that wear metals on the engine looked good before spending $$$$ on this project. After doing the intake gaskets & killing off another vacuum leak or two, this thing is running like a top now (outside of the noise in the rear end that I mentioned at the beginning). But... I want 'more' (typical American...LOL)

Since the 6.0L has a rep for having a bulletproof bottom end, we're going to rely on that, for now. At some point, depending on how these mods work out, I may decide to put on a turbo setup (which works better than a supercharger, at elevation) - if I go that route, I'll probably get a spare block and build it up, given what I'll be spending on the turbo(s).

So... with all of that said... let's get started tearing this beastie apart!

(to be continued... )


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If you decide to re-locate the Knock Sensors... Look into the Clearance Issues for the Header Installation... especially if long Tubes are your Choice. What an Awesome Truck, Brother!


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TY, @MRRSM ! Appreciate the kind words, re: the truck. Still lots of work to do.

At this point, I doubt I'm doing headers... here's why...
- While I'm exempt from emissions testing with this truck, due to the 8600lb GVWR (amazing, in IL), and could delete cats / O2 sensors... I'd rather not do that.

- My intent is to enhance midrange / upper RPM HP & torque, where possible, for towing at elevation. 'Shortys' won't be much improvement over the OEM manifolds, and as for long tubes... well, there's the cats to deal with, that I'd like to keep.

- I don't want to make the exhaust drone while driving on the interstate. That's why I took off the Flowmaster (and while I did lose a little bit of responsiveness afterward, as measured by the 'butt dyno', I didn't regret going back to stock).

- If I do a turbo down the line, I'll have to rework the exhaust. Until I decide, I don't want to spend the time / $$$ to do it twice.

TL; DR - we'll see, but for now, I'm hanging on to the stock exhaust.

Spent the afternoon degreasing a set of valve covers and a front crank cover I picked up, thinking I was going to paint them (and wanted to get that done in the garage before putting the truck in). Then I ran across the option of powder coating, and requested a couple of quotes to have it done. So I may not be painting those parts, after all.


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FWIW... The inexpensive POR-15 "Starter Kit" in either Gloss Jet Black or what looks like the Red-Orange color of the paint on Jay Leno's Maclaren MP412C for contrast vs. the Blue Paint on your Truck would be PERFECT. This Stuff in either color would give you a durable, attractive finish on those Aluminum Valve Covers and other Cast Iron Suspension, Brake Parts and Frame Areas, too:

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Sometimes I recognize parts I'll need ahead of time, or at a certain point, and buy them beforehand. Or I find a good deal, or they'll save me time, etc. Sometimes all of these things. Such is the case with today's update.

With the amount of room I have to work in, any painting I'd have to do would need to be before the truck went in the garage. Since I wanted to dress up the engine a bit (nothing really fancy), I picked up a set of spare valve covers and a spare timing cover. I think I got these for $25 for all three via CL.

I didn't just want the valve covers painted -- I wanted a 'crinkle' (or 'wrinkled') finish. As it turns out, VHT makes some paint that is supposed to do exactly that, although colors are limited. So I picked up a couple of cans of that, along with some VHT primer. A couple of shots...


The observant reader will note that I left the timing cover seal in place. Popping it out after the paint dried produced this nice-looking result:


To activate the wrinkle/crinkle, VHT specifies 200 deg F for 1hr. Since I didn't want to potentially ruin my household range, I broke out the heat gun. However, all I did was bubble the paint off in the spot where I tried it (the paint is rated to 500F 'intermittent', so I guess they want the heat to be exactly (?) 200F. For now, we'll put these aside, as we're not going to need them for a bit. If anyone's used their household oven for VHT-style paint, and didn't ruin their oven, let me know. I still have time... lol. Otherwise, they'll get their 'curing' after they're installed on engine.

When I first started imagining this project, I always envisioned removing the heads & replacing the lifters when the new cam went in. After calculating what it would cost to recondition the heads (and potential extra costs of acquiring a new one if a crack was found, I decided to pick up an already reconditioned set, to save time / effort (also, '317' castings are supposedly known for developing cracks; you find out via pressure testing the head). Found a nice set of 317s ready-to-go; I think I picked these up for $225 on CL a little over six months ago. I double-bagged them and put them away; when I brought them out, they looked like this:


Yeah, that's rust on those springs / retainers. So, the lesson for all is... if you're going to store heads, coat them with something so they don't rust!

In my case, I wasn't keeping the springs anyway, so I stripped them out, gave the heads some additional cleaning, and replaced the springs with these...


No, those aren't blue to match my truck... they're GM LS6 springs, colloquially known as 'blue beehives'. The retainers / locks are the matching LS6 components. About $80 for the springs, close to the same for the retainers (they're titanium, IIRC), and the locks were $40 (? - not sure, but I'll look it up). Add $17 for a spring compressor (a cheapie, but worked a treat) to swap everything out with, and another $17 for a set of digital calipers to take some measurements with (I'll get into this, if people are interested, although I didn't take pics of me actually taking the measurements).

Why'd I choose these springs? Because they're a very cost-effective (& popular) choice for cams up to .550 in. lift. The stock-style springs wouldn't handle that amount of lift, plus they had 230K on them (you'll 'hear' me saying that a few times during this build). I knew nothing about the springs the new heads came with, so didn't plan on using them. The heads came with new seats / seals already installed; valves are stock LS (no fancy sodium-filled, etc.)

Before I started the project, I had gotten a copy of this book (available via Amazon; I got the Kindle version for $14 (had to look it up to get the pic, so here):


I find this book pretty useful. While I'm not rebuilding the short block / rotating assy at this point, I may at a later time. I do refer to it often.

That brings me to why I selected another set of 'stock' 317s, vs. going with the 'hot' 799s / 243s...

I did consider heads with smaller combustion chambers. But after speaking with a local machine shop resource, I decided to keep with the 317s, and not have them worked further (e.g.; porting). There's a couple of reasons behind that.
One is my intended use (towing / torque, not max HP / racing).
The other is a desire to be able to use crap gas. Out west, as you get into high elevations, octane is lowered -- the 89 RON that I get at my local gas station here in IL becomes 86-87 RON (as labeled on the pump) in Montana, for example. E85 is another option that I want to be able to use (as it is higher in octane); you see that used frequently up in the mountain areas, as well.

At 8mpg with the trailer on the back, I'd rather not be stuck buying premium. And with a 26gal tank (only size with a CCSB, in this gen truck), fillups come often, on the road. Cha-ching!

Finally, the low-compression 317s (9.4:1 stock) are considered a great option for boost. While I've always salivated over putting a blower on an engine, it turns out that a turbo would be a better option for this truck, and towing, as turbo-equipped vehicles do better with less available air than a supercharger. So, you could say, I'm planning ahead a little bit. If I do it as a 'stage 2' project, I won't be going crazy with the boost - most likely sub-20lb. But that's a ways down the road. And I need to edumacate myself on turbo building / tuning, first.

And that's today's update. Questions / comments, as always, are welcome.
Also, while I'm listing pricing here, it's not intended as a 'brag'... only to indicate what this costs me, in case someone else is looking at doing it. If I swung a really good deal on something, I'll indicate same. I do try and look for best deal available (from reliable sellers).
If you don't like seeing the running costs, let me know (actually, let us know if you do, as well).

So far... (I'll try and get this into a spreadsheet format later).
All costs in USD, unless indicated, but DO include shipping
Labor costs are not included, and you should not assume I complete anything at 'book rate'. If I could, I'd be a pro.

Timing / Valve covers - $25
Paint - $30
New 317 heads - $225 (deal - roughly $100 under similar; twice that if I rebuilt mine)
LS6 springs/keepers/locks - $208
Tools (as above) - $34

Total so far: $ 522.00

Next up: I replace a rear O2 sensor (not part of build, but want to do it before disconnecting exhaust manifolds). I'm not going to document changing this out; just making a note of what I'll be doing before picking this back up in earnest (with parts disassembly)
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do you have 220 in your garage? maybe, you could find a "junk" stove, like the range part quit working but the oven still works, for free or really cheap. use it for what you need and haul it in for scrap.


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@Beacon - No 220VAC. And even if I did, no room to put in a range. Can barely fit the truck in!

Here in the Land of Lincoln, a majority of us have basements, but the energy source of choice for cooking & heating water is natural gas, not electricity. As a side note, we have the most (?) nuclear plants of any state, but pay a rather expensive KwH rate, 'cos it cost lots of coin to build those plants in the '70s & '80s. (That reminds me to check on when those plants are due to start coming up for retirement.)

TL; DR - Appreciate the idea, but not feasible for a couple of reasons.
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At our last update, we went over the heads and springs that I chose for the build.

I also replaced the O2 sensor I mentioned last time. That actually was fairly easy, once I remembered that I wanted to replace the primary, not the secondary (which uses a different harness). Bottom line, it's in.

Today's update will concern disassembly (of a lot of items) :smile: This is a long post, as a result.
(so long, actually, that I had to split it into two, as there's a 10,000 character limit per post!)

I'm not going to explain how to remove a radiator, a valve cover, or a water pump. There are other ways to get that info, and some of you are very familiar with those things, anyway.

I wanted to remove the fenders, and have access to both sides of the engine. But I'd have to pull the hood to do that, and I'd also have to remove all of the front end parts up to the timing cover, anyway. So... I took the majority of the front off the truck. The bonus is that after all of this stuff is out, there's a lot of room to stand in the front (on the frame crossbar, if needed), and just reach right to the back of the engine, as needed. Of the three times I've removed the intake from this particular truck, this one was the easiest. Even disconnecting the fuel lines was easier than normal.

Some assorted notes on disassembly...
- Doing something like this *requires* bagging and tagging bolts, screws, clips, etc. There's just no way around it, as there's too many parts to keep track of & remember.
Get some sandwich bags, and some labels. Tip: Just put the label inside the bag - no need to peel / stick, and no worries about the label getting damaged / lost.


The bags (along with some zip ties) also are a nice way to protect all of the cooler, fuel, etc., lines that are still in the truck from getting contaminated / leaking fluids.

I figured out by depressing the Schrader valves that there was no refrigerant in the system. So I disconnected the condenser, rather than twist / kink the metal lines further.
The seals tend to become brittle & leak refrigerant, so I'll pick up a kit to replace all of them when I'm putting everything together. And I'll put a vacuum pump on the system afterward, to test things out.

Taking out the fender liners gives additional access through the side, which is a great thing to have - not only for spark plugs and boots, and exhaust manifold bolts, but for the lower head bolts, as well.
My p/s liner was cut / damaged, anyway, so ripping out the old one was a no-brainer. I had put a new liner on the d/s a few months back. Ripping it out again for access, I finally figured out where my P/S fluid has been leaking from - the hydroboost module (from the weep hole) - turns out it's a fairly common thing, as they sell seal kits for it. So I ordered one up today and should have it by the middle of next week.

When I got the truck, the front bumper cover (for a C3 Denali) was held on with only 4 of the 8 or so bolts it came with from the factory. So it was pretty easy to remove the OEM cover that I had put back on the truck.

I was able to get the fan / clutch off without air tools... leave the serpentine connected, and put a cold chisel on the left side of the nut (as you face the front of the engine). A few blows will break it loose (and since the truck looks to have a recent (?) water pump, I'm not going to pretend that if it were the original WP on there for 17 years, that I'd have had as easy a time. Still, not firing up the noisy air compressor was fine with me.)

When you remove the WP, be prepared for about 1/2 - 3/4 of a gallon of additional coolant to come out. So have a pan under the truck, ready to go. If your pan is small, only loosen one side of the pump at a time; it takes awhile for the coolant to finish draining from the top of the motor. Just like it took to finish draining from the radiator, when you opened that up.
One other thing about draining coolant - even though GM was to have discontinued putting the petcocks in radiators from MY '03 onward - I found out after the radiator was out that it actually had a petcock, all the way on the d/s of the radiator. So check, b/c you never know. Mine was missing the rubber hose that tucks up into the fan shroud area -- but I did have the petcock. Wish I knew ahead of time!

The crank bolt / dampener: This was a bit of a challenge. Ok - it was a b!tch...

I had purchased this tool ahead of time, in hopes it would easily remove the bolt. It *did* remove the bolt - but it needed some help from me, first. Outside of that, it is a useful tool, and has power -- but it is heavy, and not terribly well-balanced. It's also a "all or nothing" w/ regard to the trigger - no variability to the power / speed. Don't try to attach a universal joint anywhere in the socket chain on it, as the torque will send it flying.


First off... Immobilize the crank, because even with the serpentine belt on, and with sealed heads maintaining compression, the crank will just turn when you put a breaker bar on it. 24mm socket, btw.

I had planned ahead and picked one of these up from Amazon for about $20. It was pretty easy to drop the starter (hey - it ain't a TB / Envoy!) and attach this tool to lock the flexplate in place. Bolts are also supplied (but they're a different size head than the OEM starter bolts. Mildly aggravating to swap sockets, but I managed.) LOL The worst part of dropping the starter was figuring out the sizes of the 8 and 10mm nuts to disconnect from the truck wiring.

With the flexplate immobilized... you, the impact, and your breaker bar can get to work.

First, I tried the gun. HF may advertise 1050 ft/lb of torque, but it didn't look to budge the bolt. Time to get out the breaker bar, with cheater pipe.
Unfortunately, I'm not as strong as I used to be, and I didn't think I moved the bolt. Back to the gun. On a hunch, I reversed direction - and it moved slightly in the tightening direction. So I rocked it back and forth for a bit. Didn't seem to move further. Back to the breaker / cheater. No, I didn't get any stronger. Hooked the gun up again, and it moved a little more when I alternated directions. Now I knew I'd be able to eventually get it off.
Took about 5 minutes, back and forth. But it finally let go, and the 24mm bolt spun right out. Looked like it came out very nicely, too.

On to the dampener...

I knew that the dampener had 3 'slots' or 'indentations' on the back side, in the center hub. That's where I attached my 3-jaw pullers. Which either didn't fit, or one of the jaws was out of commission (cheap HF crap), or the forcing screw wasn't long enough, or the cone at the end wasn't wide enough (I did slightly gouge the crank snout, just inside the outer surface). Off to rent a 'Chrysler' puller from AAP.

The Chrysler-specific tool was made because their balancers are the same as GM's - there are no threaded holes in the balancer to attach a 'duckfoot' puller to.
The nice thing is, they are supposed to be 'just right' to pull LS balancers, too. In those slots I mentioned earlier.
GM also molded 3 'tabs' on the legs of the balancer; that's how the J-tool connects. But we won't reference that tool, because it's expensive, and you don't need it.

Got the balancer puller kit home, and as it turns out... the forcing screw on that was too short, as well. The kit has two 'rods' that are to be inserted into the crank opening, but they're not long enough.
Now I'm getting p!ssed, because I've wasted a lot of time if I can't get that balancer off. But I eventually got it off. Here's how...

- Put some oil on the outer lip of the crank snout
- Get a large 3-jaw puller (I used an 8"), and a 22mm socket (short is fine)
- Set up the puller so that each jaw rests against the back side of those 'tabs' that I mentioned. This means the legs / jaws of the puller will need to twist a bit, to lock in. Place the hex end of the socket against the crank snout, and turn the forcing screw so that the conical tip is resting against the square 'drive' end of the socket. Then start turning the forcing screw.

What happens in this arrangement is that the forcing screw will not reach the end of its travel, resting against the socket. But the jaws will start drawing off the balancer.
Note -- you will likely need an impact wrench to turn the forcing screw after a few turns. Or, you better be REALLY strong.
After several seconds (depending on how slow and careful you are, and how many times you stop and check alignment, etc.) -- the balancer will be drawn off the crank. Halleh-frickin'-LU-jah!

Now the timing cover can be removed. The bolts are all the same length -- even the two on the lower side, underneath the cover.

I removed the timing cover now *just* to check if someone had already put a cam in -- this engine pulls stronger than the last 6.0 I had (I actually owned both trucks at once, so I knew the difference). As it turns out -- this engine looks stock -- no upgrades, just a lot of varnish & sludge (230K, remember?) So I put the timing cover back on, and went back up to the top of the engine, as the rocker arms have to be loosened, at a minimum, before messing with the cam gear / bolts. Do NOT touch those cam gear bolt(s) yet.

Now go and remove whatever you were using to immobilize the flexplate, so that the crank can turn again. Then thread the old crank bolt back in, by *hand*, until it seats. Get your 24mm socket and breaker bar handy, you'll be using them in a few minutes.

(to be cont'd... )




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Here, you see the top of the motor with the intake removed. Unless you've recently had your intake off, say, to replace your knock sensors (Gen III engine), I can guarantee you that the surface area will NOT look even this 'clean'. I had done mine recently.

If you have original knock sensors / harness, now's the time to order replacements. You can see my sensor harness is new, as it was replaced just a few weeks earlier, along with the knock sensors. If your harness is old, the connectors under those rubber covers are going to be very brittle, and the retaining tabs *will* break off (you squeeze them to release from the sensor, once you've created some slack between the rubber covers you pried off and the connector).

Thankfully, the harness isn't that expensive. If you have a Gen IV engine, or want to relocate your Gen III sensors to the Gen IV locations on the side of the engine block, then don't worry about breaking the sensor connectors, and you can probably leave those sensors where they are, unless they're new. In which case, you already know you need a 22mm deep socket to get them out.

Leave the valley cover in place, for now; it'll help keep the internals cleaner. If you have a Gen IV engine with cylinder deactivation and want to remove it, get your parts ordered now (usually as a kit.)

Remove the boots from the spark plugs. You can leave the end that attaches to the coils in place, if you like. You don't have to remove the spark plugs (I didn't), but you may encounter some clearance issues removing the head bolts later on, if you don't. If you remove them, label which cylinder each plug was in, so you can evaluate the condition of the plugs / cylinders afterward, if any look 'bad'.

The exhaust manifold bolts are 15mm, while the mount for the dipstick tube is 13mm (thanks, GM). If your bolts haven't been recently replaced, like the prior owner did with mine, you're almost certain to break one or more of them off, due to corrosion / heat, over the years. Go ahead and remove those bolts now, because after the valve covers are off, you'll be ready to remove the head bolts & the heads, if you're going the same way I am. The oil dipstick tube will easily (!) pull out of the pan, and it'll be much easier to remove the exhaust manifold, if you pull it.

I was able to get five of the six nuts off the exhaust studs easily with the electric impact. The sixth one (in the least accessible place, naturally) came most of the way out, but the stud spins freely. I'll worry about that after I get the heads off. I know I can get in with a hacksaw & remove it, no problem.

On to the valve covers, so we can loosen those rocker arms, pull the pushrods out, and finally be able to spin the cam and push the lifters up into their trays. I'm removing my heads, as I'm putting new lifters in, as well as new heads. But the rocker arms still have to be loosened up and pushrods pulled, even if you aren't going to replace your lifters (which I don't recommend, if you have a higher mileage engine like I do).

While some people advise that the coil pack frame can be left in place (after you disconnect the wire harness from it), and removed with the valve cover all in one piece, you're really not going to be able to do that until all four valve cover bolts are removed - and the two inner ones are under the coil framing. So get started removing the five threaded studs that hold the coil frames onto the valve cover (10mm, and does not have to be a 'deep'). You *can* leave one at the very end connected, and swing the frame upward, once you break the torque on it -- then remove the valve cover bolts. Once that's done, swing the frame back, lift off the cover and put it aside. Tip: Label which bank each coil pack assembly was on; it may be helpful if you have to trace any issues later on, if you reinstall the coil packs on the sides they were originally on. That's assuming you're not putting new coil packs in (I'm not).

And now, feast your eyes on that valvetrain... mmm--Mmm! That's what I'm talkin' bout...

The rockers can be removed in one group, via a bar that holds them. However, don't just put your 8mm socket on the rocker hold down screws and start turning freely, yet.
First, make sure that the rockers you're going to loosen aren't fully compressing the springs. If you need to, turn the crank (always clockwise) to get the rockers you want to loosen off the compression stroke. Then loosen the rocker arms. That way, you won't strip the threads (they're aluminum, remember).
You'll actually be able to hear the air escape from the cylinders as you turn the crank.
You don't have to fully remove the rocker to get it off the pushrod. If you're removing the pushrod, label them as to cylinder, whether intake or exhaust, and identify which end is top. Why do this? Because you want to examine for wear - and also to see if any are bent. Bent stock pushrods are a fact of life with the LS motor. You can check them by rolling along a flat surface. But clean them first.

Fully loosen the bolts from the rocker arms (8mm). If you leave them in the rocker arm, you can lift them all out at once with the bar they sit on. Convenient.

I put the motor at TDC before removing the cam sprocket bolts & the sprocket.

I had the idea of leaving the pushrods in, as I spun the cam - that way, I could tell if any weren't at the top of their travel, and didn't get captured in the lifter tray.
However, this didn't work too well. I pushed the pushrods down until they stopped their travel, then put a WP bolt in the cam and started turning.
About 3 or so turns later, the cam stopped moving. I knew enough not to force it, and went on to pull one of the heads.

The five top head bolts (10mm) get pulled first. These can actually be reused, if desired. They're torqued lightly enough that a 1/4" ratchet will loosen them up.

When you loosen the 10 main head bolts, try and work from outside toward the center, if you can. Also, break the torque on the bolts by hand -- that way, you'll be able to tell if any of them look like they will cause an issue. I broke them in reverse order, and gave each 4 x 90 degree turns to start, before fully removing any. I figured that way, the clamping would be released fairly evenly (although the LS book I mentioned earlier didn't specify this). Get a drain pan ready, because coolant will start draining out of the back side of the head / block, once you back the bolts out 5-6 turns or so.

If you have a 2003-2004 engine, check the length of the two upper bolts, relative to the eight others - if they're shorter, make sure to replace with the same length bolts. If you buy a set of bolts, they're always grouped by '98-'03 and '04-onward. But consider this... there have been people with 2004 trucks that had the *shorter* bolts. And some 2003 trucks had the *longer* ones. Chalk that up to GM's parts bins (hopefully, the right bolts got installed into the right blocks, back in the day). My 2003 had the shorter ones, btw.

Also, with regard to the bolts, I was originally going to replace the head bolts with a new set of GM torque-to-yield (stock). However, some of the bolt locations make it a bit difficult to reach, with the engine in-car. Especially in the very back of the motor. I know it will be worse when installing them, given the TTY method. Given this, I'm seriously considering a set of ARP bolts now, as they don't require a TTY sequence. They're also reusable. But they're also hella expensive. I had already decided I'd use an ARP crank bolt; now I get to decide if I want to try TTY bolts or not.

For those of you who ask "why not put in a stud kit" ? Because I'm worried about clearance to put the head on with a stud kit, with the block in the truck. Besides, I'm not racing, just towing :biggrin:

With the last of the bolts out, you can lift off the head. I was pleased to see that I could still see the honing marks (crosshatch) on the cylinders on the side I pulled. 230,000 miles, and the cylinders were pretty much as they left the factory. That was nice to see.

There will be coolant in the three rearward cylinders on bank 1, if you put the crank at TDC. Get that out now, and dry the cylinders. I put some WD-40 in mine, to keep moisture from starting to rust the cylinder walls (that's what that little white spot is, on #5, below).


Finally, I got to pull the lifter trays, to see if the lifters were successfully captured back into the trays, when I spun the cam.
Why do I capitalize that? Because if you are going to install a cam in a high-mileage motor, without replacing the lifters, and expecting to push them back up into their trays, then inserting the rods in the upper oiling passage in the block, to retain them as you remove the cam -- you may find that they weren't captured, at all (when one or more of the lifters makes a 'clink' sound as it falls into the rotating assembly).

In other words... if I'm personally putting a cam into a motor with a lot of mileage - I'm going to pull the heads, myself. Period. I am *so* glad I didn't try pulling the cam after spinning it.

I was able to get one of the lifters out with a magnetic tool (you can see it sitting on the valley cover, above). So I'm not too worried about the lifters dropping into the rotating assy. But I know that one or more of them is caught between the cam lobes and the lifter bore.

Stopping for today, and will pull the other head / all the lifters out tomorrow, then remove the cam. But I've got enough of it apart to stop here, and update the thread.

(out of room here; will update cost totals at next update)


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Putting in one more update... I had to reattach pics to the 2nd post, and they display in 'miniature'.

If there's something I wrote about that you'd like to see a picture included on (besides the above ones), let me know and I'll see what I can do about adding it (full size, for visibility). However, I'm up against the 10K text limits, so if you need further explanation of something (as if!), that'll have to be via a new post. Thx.

Since I made a 3rd post, I'll put the cost update, here...

Next up - put in another parts order and clean, clean, clean, while I'm waiting for the parts.
Tune in next time, when we get to see Reprise use a Roloc wheel!

Cost update:

Parts: None

Tool to immobilize flexplate: $22
HF Electric impact gun: $80
Ares dampener puller tool: $35 (didn't use, but stuck w/ the purchase)

Subtotal: $137

Running total: $659

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