Nadthomas 2007 Yukon Denali 200k Mile Re-build

[nadthomas]

So, short back story. I bought this 2007 Yukon Denali off my boss about 6 months ago knowing it needed some maintenance and cleaning, but was generally maintained with regular oil changes, etc, and still drove well. Before I bought it I did a leak down test, since the I had heard the exhaust manifolds leaking for the past 2 years and I wanted to make sure there wasn't burnt valves. Leakdown test came back perfect, so I was pretty confident with some repairs it has some decent life left in her. It was also originally purchased to be a newer/nicer replacement for our 3rd vehicle. As it turns out, my wife liked it a lot better then her current DD, so she will be taking the Denali as her new DD. Don't get me wrong, I enjoy the Denali as well, but I would rather weave through traffic in my BMW and row my own gears.



So, I cleaned it, clamped the exhaust manifold, and fixed some of the minor issues like TPMS, bad key fobs, and some broken interior pieces. Then we drove it through the winter and spring to identify any additional problems, and how I wanted to go about fixing them. Ultimately I came to the determination that I was just going to pull the motor and give it what I'm calling a light refresh. After that I will rebuild the suspension. The end goal is to have a reliable daily driver for the next couple of years, then it will probably moved back to being a 3rd vehicle(......then hopefully use the powertrain in a 72 Blazer......someday).

Known Issues
-Several Broken Exhaust Manifold bolts - Clamps helped, but they still leak.
-Sometimes CEL for Cam Phaser
-Slightly fluctuating oil pressure
-Both Front CV Axle boots slinging grease
-Blown Air Ride
-Occasionally firm shifts
-Also pretty much everything is covered in a think layer of dirt and grease(probably one of the bigger reasons why I want to pull the motor. Just so I can clean, I love a clean engine bays)

Before I ramble further, I know you want to see some pics. So, I'll jump to current day and fill in the details in the next couple of post. Here is how she sits in the garage today.

 

[Rocket Man]

That's a hard way to clean an engine.

 

[adventurenali92]

Looks like you got your work cut out for you! Thanks for sharing! In for progress! I love the 2007 style Denali! Why classy looking rig!

 

[kbuskill]

So what is on the to do list for the "light refresh"???

 

[nadthomas]

That's a hard way to clean an engine.

True, but notice how black the valve covers are...that was after spraying down the engine bay with a engine degreaser, and then simply green. I'll be trying some oven cleaner next.

So what is on the to do list for the "light refresh"???

Glad you asked, I ran out of time and didn't want to ramble on for too long in the first post. Here is what I plan to to do:

Engine
Remove Oil Pan and Valve Covers to check for sludge and/or debris
Replace Oil Pump
Replace Oil Pickup Tube
Inspect/Replace Timing Chain Set
Replace D.S. Exhaust Manifold (Pretty sure it is warped)
Replace both sides Exhaust Manifold gaskets and bolts
Replace Cam Phaser Actuator
Replace Engine Mounts(H3)
New Starter(Damaged the old one removing it)
New Front and Rear Main Seal
New Gaskets for anything I touch
Paint Valve Covers w/ VHT Wrinkle Red
New Plugs & Wires
K&N Intake

Trans
Remove and inspect valvebody (ie. check balls)
Replace Transmission Fluid and Filter
Replace Transmission lines

Suspension
My wife said she didn't care for the amount of body roll, and I like trucks lifted or lowered. So, down it goes. I'll be doing away with the factory air ride system, as it would both cost more to replace and adds complexity.
Belltech 753SP (2/3 Drop)
DJM Endlinks
Swaybars(Maybe)
Helper Bags(I will probably end up towing something at some point).

Others
Replace front CV axles

Of course this may be expanded on once I inspect things, but I'm hoping to stop there. I'm no expert on this platform, just a guy that tinkers with his toys, so if anyone sees something I should really address while I have it all torn apart let me know. Also, I wish it was in the budget to do headers and a cam, but maybe in the future.

 

[kbuskill]

True, but notice how black the valve covers are...that was after spraying down the engine bay with a engine degreaser, and then simply green. I'll be trying some oven cleaner next.



Glad you asked, I ran out of time and didn't want to ramble on for too long in the first post. Here is what I plan to to do:

Engine
Remove Oil Pan and Valve Covers to check for sludge and/or debris
Replace Oil Pump
Replace Oil Pickup Tube
Replace Timing Chain Set
Replace Water Pump
Replace D.S. Exhaust Manifold (Pretty sure it is warped)
Replace both sides Exhaust Manifold gaskets and bolts
Replace Cam Phaser Actuator
Replace Engine Mounts(H3)
New Starter(Damaged the old one removing it)
New Front and Rear Main Seal
New Gaskets for anything I touch
Paint Valve Covers w/ VHT Wrinkle Red
New Plugs & Wires
K&N Intake

Trans
Remove and inspect valvebody (ie. check balls)
Replace Transmission Fluid and Filter
Replace Transmission lines

Suspension
Do away with air ride system
Belltech 753SP
DJM Endlinks
Swaybars(Maybe)
Helper Bags(I will probably end up towing something at some point).

Others
Replace front CV axles

Of course this may be expanded on once I inspect things, but I'm hoping to stop there. I'm no expert on this platform, just a guy that tinkers with his toys, so if anyone sees something I should really address while I have it all torn apart let me know. Also, I wish it was in the budget to do headers and a cam, but maybe in the future.

Looks like you have a pretty good handle on things. Good luck, have fun, and post pics.

 

[Rocket Man]

I'm with you on all that, good choices. I did most of that and then some on my 02 over time with a few more goodies added. That VHT Wrinkle is awesome stuff. I did my valve covers red like you and the front cover, water pump and anything else removeable in the front of the engine in the black. All that aluminum looks terrible after awhile but after the VHT Wrinkle it stays looking good.

 

[nadthomas]

That looks great. More things might get painted, I'll have to see how I feel about them after then are clean. I may just give everything else a fresh coat of silver. I have done that in the past with good results.

 

[swathdiver]

Might as well put a new camshaft and lifters even if stock. At least check them and the cam bearings out.

Get the updated driver's side valve cover, prevents oil blow-by. Consider replacing the VVT parts while it's apart too.

 

[PG01]

That's a hard way to clean an engine.

Or the easy way....

 

[Rocket Man]

Or the easy way....

The prep work is a killer.

 

[iamdub]

List looks good for everything external of the longblock. For the intake, I'd go with an Airaid MIT instead of a K&N. A dry K&N filter (AEM Dryflow) if you insist on replacing the stock filter.

 

[nadthomas]

Might as well put a new camshaft and lifters even if stock. At least check them and the cam bearings out.

Get the updated driver's side valve cover, prevents oil blow-by. Consider replacing the VVT parts while it's apart too.

I probably would replace/inspect the cam if I had more knowledge in that area. I'm sure its only a couple of hours more work, but I'm probably going to let sleeping dogs lay on that one.

Is the VVT components you are talking about the cam phaser actuator? If so, its on my list. I will need to look into the DS valve cover. Do you have a part number?

List looks good for everything external of the longblock. For the intake, I'd go with an Airaid MIT instead of a K&N. A dry K&N filter (AEM Dryflow) if you insist on replacing the stock filter.

I like the K&N because it has more of an enclosed box around the filter. Also, never had an issue with a oiled K&N filter. I know its kind of a waste of money, but the extra intake noise makes me happy.

 

[swathdiver]

I will need to look into the DS valve cover. Do you have a part number?

12642655

 

[nadthomas]

12642655

NICE! THANKS!

Bonus, I will now have an extra valve cover to test paint with the wrinkle paint before I do the one that will be on the truck.

 

[iddqd]

Might as well put a new camshaft and lifters even if stock. At least check them and the cam bearings out.

Get the updated driver's side valve cover, prevents oil blow-by. Consider replacing the VVT parts while it's apart too.

Cam bearing is a known issue on Gen IV. If the engine is out, DO replace the cam bearings with updated parts from GM. There's even a TSB on that.

http://community.cengage.com/Chilto...2D00_cam_2D00_bearings_2D00_GenIV_2D00_V8.pdf

Worn #1 cam bearing causes low oil pressure, VVT errors and ultimately junked engine

 

[delightskinned1]

Driving 07 Denali as well and although only at around 140k I do plan on keeping it long term so I do hope you update this thread as you go as it has some good interesting info that I'm sure will be useful to alot of us in the future!

 

[nadthomas]

Cam bearing is a known issue on Gen IV. If the engine is out, DO replace the cam bearings with updated parts from GM. There's even a TSB on that.

http://community.cengage.com/Chilto...2D00_cam_2D00_bearings_2D00_GenIV_2D00_V8.pdf

Worn #1 cam bearing causes low oil pressure, VVT errors and ultimately junked engine

Thanks for the info. You have convinced me to at least take a look at the cam and cam bearings. It seems pretty simple to remove and inspect, since I'll be right there when I'm replacing the oil pump. From the research I have done so far though, there appears to be pretty even mixed opinions if the cam bearing wear that is seen is even an issue. Lots of LS motors with what looks like heavy bearing wear, but many people are not bothering to replace the cam bearings and they continue to be problem free. It also appears that AFM/DOD motors are more prone to this issue. My motor does not have AFM/DOD.

Last week I compiled my complete list of parts (which I will share), and I'm already up to $1500. Which is well over what I was expecting this project to cost, and that doesn't include new fluids. It looks like the recommended replacement bearings from GM will cost about $100. So, I'm not loving needing to add that to this project. Also, its not clear to me right now that I can even replace the cam bearings without needing to tear down the motor further.

At the moment, I'm thinking if I don't see scoring or debris I'm going to leave it alone for now. If after I get it all back together, if I still see low oil pressure I'll go back in for the cam bearings. As that seems to be the real indicator of a problem with the bearings. Additionally its hard for me to say and justify that the slightly low oil pressure I was seeing was due to a cam bearing when there is so many other common failures. Also, GM says the oil pump is rated for 200k miles, so my oil pump is clearly at end of life.

Again. Thanks for the input!

 

[nadthomas]

For documentation purposes, and to give anyone that has not done something like this before an idea, I'll now circle back now to cover the engine remove. Prepare for lots of words. Everyone can scroll down for the pics.

Its a pretty straight forward process, and there are a number of good manuals, books, and YouTube videos that cover this in more details.

To start I'm not sure if there is actually that much of a difference between a Silverado and a Yukon when it comes to engine remove, but the Hayes Silverado book seemed to miss a good bit. Not that it wasn't kind of obvious, but still disappointing they didn't cover all the things that would need to be disconnected. Most notable, the Hayes book only says the A/C needs to be evacuated on the V6 models. So, I assume there would be enough soft lines on a V8's A/C system that I could move A/C components out of the way without needing the evacuate/recharge the system. From what I can tell that is simply not the case. I was too deep in when I realized this, so I had to just crack the bolt on the condenser and slowly let it drain while I enjoyed some pool time with my daughter and for killing the world I'm leaving her with.

Since this is not something I do on the regular, step one is to get painters tape, a sharpie, and a box of quart size bags. Where possible I try to put nuts/bolts back where I got them, otherwise they go in a bag with a label. All electrical connections get labeled with the tape as well. If you have no idea what you are disconnecting is called just make 2 labels, and label each thing with the same number. For example electrical connection #4 will get connected to sensor #4, and so on, doesn't matter what it is actually called as long as it gets reconnected correctly. The very first motor I pulled I probably didn't know what half of the things were that I disconnected, but with my labels everything got perfectly reconnected the first time. Also, just because it may be obvious when your first disconnect it and how the wiring harness lays/routed, the harness may get moved quite a bit by the time you are done, and when part of the harness that runs to the bottom of the engine is laying on top of the intake as you put it back together those labels will help. There is no shame in keeping it simple in my book. Although this time, I can happily say I was able to label/name everything correctly, but don't sweat it if you can't.

Generally you are going need to do the following. Remove grill, bumper cover, and headlights. Removing the metal bumper may not be necessary, it depends on your engine hoist, but it also makes it easier to get at things with it out of the way.


Disconnect battery, remove intake, and engine cover. Drain oil from pain, and drain coolant by popping over the lower hose to the radiator and expansion tank.

Now you want to tackle getting all of the coolers out of the way. Once drained, disconnect all hoses and line to the radiator. I don't recall which needs done first, but you will need to remove all of the "coolers" (trans, radiator, A/C condenser) and upper support beam. Once done you will have clear access to the front of the motor, and visually made some good progress.

Next I tackled removing the splash shields from the front wheel wells. The starter, and the y-pipe to exhaust manifold bolts. You will want to lift and secure the truck on some jackstands. The exhaust manifold bolts were the only thing that gave me substantial problems. My 1000ft/lbs impact could not break these loose, but with a 2ft breaker bar it was pretty easy...on the passenger side. On the passenger side, two nuts came off no problem, the third one the stud snapped. The driver side is a different animal. IIRC unbolting the drive shaft helps, but access is still restricted. One of the nuts is easily accessible. The other nut, I thought I was on completely and square, but I was not and rounded it. The 3rd nut I could not find a good way to access it and get enough leverage to break it loose. I already had plans to replace the DS exhaust manifold, so I jump to cutting the nut/stud pretty quickly. Spend a couple of bucks on a carbide tipped metal blade, it will get through it pretty quickly. Unlike the hours I wasted with a dremel and old metal blades.



From there I removed the starter, and the flywheel to torque convertor bolts. Be sure to make a mark on the torque converter and flywheel so you can line them up again later.

Next I moved on to removing most of the transmission bell housing bolts. You can remove the lower 3/4 of the bolts from underneath. It was kind of slow going, but not particularly difficult. I found a deep offset box end wrench most useful for removing most of these. The top two or three bolts that you cannot get from the bottom. Well, I guess some people with 2 ft extensions can, but I suspect that is only on 2WD models. As the transfer case seemed to be in the way for me. Additionally, since I had already planned to remove the intake manifold to install a lift plate, these are pretty easily accessible once the intake is removed. So, I saved them for the very last.

From this point forward its pretty easy going. Also, IIRC at this point you can toss your wheels back on and take it off the jackstand to make it easier to work on. You just need to work on getting all of the hoses, lines, and electrical connections disconnected and moved to the side. Unbolting things as needed. Take your time, bag, and label. I kind of started with the few sensor connections at the bottom. Then I moved to the top/intake/injectors which has the bulk of the electrical connections, and then disconnected anything left in between. A note, the power steering and alternator bracket can be unbolted form the engine as a unit. Then use a bungee cord to hold the entire assembly off to the side.



With the intake manifold off and everything else out of the way, you should now be able to easily reach the top transmission bolts. Use a jack and piece of wood to support the transmission. Remove the remain trans bolts and the 3 bolts for each of the engine mounts. Hook up your engine hoist to the lift plate, and put just a little tension on the chain and taking some pressure off the engine mounts. Give everything a wiggle. Double check to make sure the engine is evenly separating from the trans, otherwise you may have missed a bolt. Also double check for any hoses/line/electrical connections. Lift a little more and wiggle a little more, inspect, rinse and repeat until its out.



I also took a number for photos for reference along the way to make sure I route hoses, lines, and electrical connections the same way when I put it back together.

 

[nadthomas]

Now, an actual update! At this rate, I might get this done before the snow flies. It was sitting untouched on the engine stand for 2 weeks. Well, I finally took my first real stab at de-greasing the engine. I used oven cleaner, which I know some people on the internet have voiced concerns about using on an aluminum block. After some reading and discussing with a friend that recently used oven cleaner on the aluminum bumper on his Grand Wagoneer, I determine the results would be acceptable. You don't want to use oven clean on any polished parts, unless you plan to wet sand and re-polish, but on cast aluminum block like the Denali I think its fine. It does darken the surface of the aluminum, and will leave a bit of an ashy coating behind. I did two heavy coats of oven clean, and just rinsing with water in between coats. The first cost I let sit for about 5 minutes before rinsing. The second coat I let set for 20 minutes, which was a little to long as the sun came out and it started to dry. I was then running out of time, so I quickly hit a few of the pockets that still had grim with more oven clean and a bush.

Given the thick heavy layer of dirt and grease that covered most of the engine, and really minimal scrubbing the results are pretty good. Also, nothing was damaged as a result of using the oven cleaner.

If you are just looking to get a 95% degrease on your engine you could stop here. Once I get done replacing everything. I'm going to go back over the entire thing in detail with Simply Green and brush to prep it for paint. I will then hit it with some silver engine paint to make it look factory fresh.