OK, Bought a 07 with a couple problems today.

[SpareParts]

So once apart, I'm starting to think maybe his story was not entirely BS but no way to know for sure.
The cam sensor looked newish, The VVT Magnet is the new style and it also had a new VVT solenoid but why not change the oil pump and o ring. Seems like a no brainer to me.
After installing a new milling 365HV pump and swapping it to the green relief spring.
Im happy to say i have 60PSI cold oil pressure. Hot oil pressure seems to be 35ish PSI.

 

[SpareParts]

I'm cautiously optimistic from previous experience with this problem. If oil pressure remains steady for the next couple of months i'll be fkn ecstatic.
At least for now i can move on to other stuff that needs to be fixed.

 

[petethepug]

The oil pump swap without removing the pan is awesome!

Reminds me of the short lived TV series Big Fix Alaska where master mechanics went out to unforgiving, inaccessible places and working miracles on heavy equipment that should have been put out to pasture.

Up North, if you’ve got heavy equipment in the bush, it’s all about thinking out of the box to keep it running.

 

[SpareParts]

Grew up in a Heavy equipment shop the parents owned, so been working on everything with an engine all my life. Don't trust anyone else to do it so i have to and sometimes ya gotta get creative to get it done but, At 63yo it's getting harder to get it done.

 

[SpareParts]

Not really looking forward to today's big adventure, Changing the DR side engine mount.
Some do it from the finder well some do it from underneath. Either way they all say it suck2.
Report my experience with a few pics, probably.

 

[89Suburban]

Good job brother

 

[SpareParts]

Got that mount changed. Slight pita but not to bad really. Sure is nice to not have that clunk taking off from a stop!
The old mount was trashed bad enough that the retaining pin holding it together was bent. Must have been changed before as the heat shield is gone.
No matter how i tried i could not get the new mount in with the heat shield either, even with the drive line out.
I could have installed it if i had removed the exhaust manifold but it already has 2 broken bolts and i did not want to spend the next couple of days trying to weld nuts on to get them out.

 

[SpareParts]

Before i finished, i also changed the oil again with Royal Purple and a Wix XP filter.
After changing the engine mount and a cold start the oil pressure was still holding steady at 60PSI cold. i took it for about a 20 mile highway drive so it was good and warmed up. Idling the hot oil pressure is about 23ish PSI. Now i have good solid numbers and a base to judge how its doing.
This time in the bottom of the oil drain pan there were no shiny chunks of metal so that's good but time and miles will tell.
Maybe the shiny chunks were left over remains from before they changed the cam bearings. I still highly doubt the PO did that though.

On to other stuff. Sorry might get kinda long but i want to document and use it as a reference for later.

When i was under it today, I finally had the chance to go over it a lot better since i bought it 3 weeks ago. I have some work ahead! In no particular order of importance.

1: The front diff fluid was very low. I assume from leaking seals. All the mounts on the front diff are shot. It rocks up and down on the mounts. I'm thinking it might be easier to buy a used one.
2: The left front axle needs to be replaced. Makes the usual bad noises when turning and the CV boot is torn. (done 11/24/2024)
3: Lower ball joints slightly loose, so might as well rebuild the front end with the miles it has. Drives good, does not have any uneven tire ware.
4: Service Transmission. Fluid does not smell burnt but is dark. Trans shifts normal. (done 11/16/24)
5: Transfer case. Change output shaft seal. About 2 cups low from leaking. I did change fluid today.
6: Replace DR Seat. The seat is solid but, something seems broke inside on the lumbar support does nothing but make a grinding noise. Bottom heat does not work.
Seat heat fixed itself. (11/1/24)
7: Oil pan gasket needs to be replaced. Will fix when front diff is out.
8: Rear lift gate. Replaced the motorized latch part on the lift gate and it will open using the outside handle now. Replaced outside window switch so it also works now.
Replaced window struts and lift gate struts (11/17/2024)
9: Front struts. Not sure what to do. Level or 4in lift? (New Front struts ordered 1/26/25)
10: There is a broken mount bolt on the DR side where the sway bar mounts to the frame. (Fixed 1/5/25)
11: Need to check rear diff fluid. (done 11/16/24)
12: Exhaust manifold bolts.
13: Fuel pump changed (done 12/23/24)
14: DR Motor mount changed (done 10/15/24)
15: 4 New TPMS sensors (done 12/30/24)


That's about all i can find that needs attention. What i would expect for what i paid and the miles.
Everything is a do in a weekend job, just takes money.

 

[SpareParts]

Picked this up today for 20 bucks at the wrecking yard. Debating on painting it black like the one on it.

 

[SpareParts]

Oh, Also i can get the Instrument cluster for $50 and the bezel also. Trying to decide if it's a worthwhile mod or not.

 

[Geotrash]

So once apart, I'm starting to think maybe his story was not entirely BS but no way to know for sure.
The cam sensor looked newish, The VVT Magnet is the new style and it also had a new VVT solenoid but why not change the oil pump and o ring. Seems like a no brainer to me.
After installing a new milling 365HV pump and swapping it to the green relief spring.
Im happy to say i have 60PSI cold oil pressure. Hot oil pressure seems to be 35ish PSI.View attachment 442205View attachment 442206

I'm running the same oil pump in my 2012 XL Denali and I see the same oil pressures. Good!

On the motor mount, you're going to want some kind of heat shield in there or that rubber fluid balloon in the new mount will dry out and crack faster. I was able to get a new one in with the heat shields when doing it from the side through the wheel well. Too late now I suppose, but rigging up some sheet metal in there would seem a wise investment of time.]

On the diff mounts, they can be replaced with the diff still in place. Takes a little finagling but I was able to do it on my '07. If you decide to pull it out, it might be worth just resealing yours. It's not a terrible job on the bench.

 

[SpareParts]

Time will tell if putting a new pump in cured it or just prolonged the engine swap.

I figured i would need to change the mount again when i fix the broken exhaust manifold bolts if i don't get to it soonish.

Yeah, New mounts are the way to go for sure. I wanna drop the diff at the same time and change the oil pan gasket.

 

[petethepug]

GM spent millions to figure out a way to make replacing the heat shield impossible during a motor mount swap. It ensures they sell more motor mounts.

 

[SpareParts]

Today i changed the Transmission filter and fluid.
Dropping the pan was not too bad. Had to pry the Y pipe down a little so i could wiggle the pan out.
I did the trans oil change by unhooking the top cooler line at the radiator. After about 14 quarts of fluid it was running nice and new looking red.
Last thing im going to get to before it snows i think is, Changing the DR side axle and wheel bearing.

Motor mount would be easy to change without the exhaust manifold in place. I am just afraid to take the manifold off for fear of more broken bolts, 2 are already broke and the rest are rusty crusty. I don't feel like spending the weekend out in the driveway trying to remove broken exhaust manifold bolts right now.

 

[petethepug]

Your hunch on the exh man bolts is correct. On our 08 YXL Denali had 2 break off deep on the block. My Indi tech buddy spent almost 5 hours extracting them.

We joked they must have been locktite’d but pretty sure GM had a bad batch of studs on the early motors.

It’s definitely worth adding the ARP studs to these aluminum blocks.

 

[Geotrash]

Today i changed the Transmission filter and fluid.
Dropping the pan was not too bad. Had to pry the Y pipe down a little so i could wiggle the pan out.
I did the trans oil change by unhooking the top cooler line at the radiator. After about 14 quarts of fluid it was running nice and new looking red.
Last thing im going to get to before it snows i think is, Changing the DR side axle and wheel bearing.

Motor mount would be easy to change without the exhaust manifold in place. I am just afraid to take the manifold off for fear of more broken bolts, 2 are already broke and the rest are rusty crusty. I don't feel like spending the weekend out in the driveway trying to remove broken exhaust manifold bolts right now.

When the time comes to do those exhaust manifold bolts, this tool will save you a heap of trouble: https://a.co/d/5v9DEUG

 

[j91z28d1]

good to see the price of those going down.

 

[SpareParts]

Changed this out today. Really not to bad a job
I did not think the wheel bearing was bad but wanted to change it out as an, As long as I'm in there might as well change that also.
The old wheel hub does not really feel bad but man driving it now is definitely quieter and of course no crunching noise turning now.
I used Detroit Axle parts. Used em before without a problem and I don't expect I will this time. Electrical stuff is always OEM if I can get it.
Another successful repair!

 

[SpareParts]

Forgot about this pic. Took it sitting in the parking lot at work because of the mileage.
This was before I changed the oil pump. Also shows fuel empty when full and turns the check engine on. After about 20 miles the gauge starts working again.

 

[donjetman]

Changed this out today. Really not to bad a job
I did not think the wheel bearing was bad but wanted to change it out as an, As long as I'm in there might as well change that also.
The old wheel hub does not really feel bad but man driving it now is definitely quieter and of course no crunching noise turning now.
I used Detroit Axle parts. Used em before without a problem and I don't expect I will this time. Electrical stuff is always OEM if I can get it.
Another successful repair!

Dec 2023 I used Detroit Axle etc to rebuild the front end of our Denali: https://www.tahoeyukonforum.com/threads/front-end-refresh.145676/
no regrets so far