Sanity And Parts Check

[badbaddolemite]

Hi All,

I apologize in advance as I am sure this has been beaten to death already. I have been through the forum and it appears that the threads are fairly old, so I was hoping to get a sanity check in 2021.

I have a 2008 Tahoe LTZ VIN 0. Passenger side head gasket is blown I think between 4 & 7. I plan to pull the heads this weekend and will be taking them to a local machine shop to have them checked out. Assuming they are good, or can be rebuilt, the machine shop can take care of that for me.

Prior to the HG failure, I had all the symptoms of the DoD problems. I am not interested in converting, and would like to repair. The bottom end (hopefully) seems good. I am thinking a top end could get me another 100k. I am at 200k already, but a cylinder bore inspection and smooth running engine has my hopes up that the block and rotating assembly are good. I am in Alaska so getting a new motor or even a long block is really hard to do right now.

If possible, could someone have a look and see if the parts below are good and make recommendations if I should change or add?

Fel-Pro cylinder head bolt set
Fel-Pro cylinder head gasket set
AC Delco DoD lifters
AC Delco standard lifters (are other brands okay or should I stick with OEM?)
AC Delco pushrods
GM Genuine front and rear valve lifter guides
Dorman improved design VLOM

Would it be worth it to consider the following parts since I am in there

Oil pump/pickup assembly?
Water pump?
Timing set?

Any other comments or advice is greatly appreciated. I am a professional electrician but an amateur mechanic. I really appreciate what you guys do.

Thanks in advance.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

Our folks on this Forum knowledgeable in the areas that you discuss will chime in.

 

[OR VietVet]

Welcome to the forum from Oregon.

I like the Fel-Pro, GM and AC Delco parts but can the Dorman part be upgraded to a factory part? Also, if I was in there I would do as you plan: all your add ons and then some. Anything you come across, do it, especially since you have 200k now and expect 100k more. Hell, I got 136k on my 05 and I am "throwing parts at it" right now.

 

[Geotrash]

Hi All,

I apologize in advance as I am sure this has been beaten to death already. I have been through the forum and it appears that the threads are fairly old, so I was hoping to get a sanity check in 2021.

I have a 2008 Tahoe LTZ VIN 0. Passenger side head gasket is blown I think between 4 & 7. I plan to pull the heads this weekend and will be taking them to a local machine shop to have them checked out. Assuming they are good, or can be rebuilt, the machine shop can take care of that for me.

Prior to the HG failure, I had all the symptoms of the DoD problems. I am not interested in converting, and would like to repair. The bottom end (hopefully) seems good. I am thinking a top end could get me another 100k. I am at 200k already, but a cylinder bore inspection and smooth running engine has my hopes up that the block and rotating assembly are good. I am in Alaska so getting a new motor or even a long block is really hard to do right now.

If possible, could someone have a look and see if the parts below are good and make recommendations if I should change or add?

Fel-Pro cylinder head bolt set
Fel-Pro cylinder head gasket set
AC Delco DoD lifters
AC Delco standard lifters (are other brands okay or should I stick with OEM?)
AC Delco pushrods
GM Genuine front and rear valve lifter guides
Dorman improved design VLOM

Would it be worth it to consider the following parts since I am in there

Oil pump/pickup assembly?
Water pump?
Timing set?

Any other comments or advice is greatly appreciated. I am a professional electrician but an amateur mechanic. I really appreciate what you guys do.

Thanks in advance.

Definitely Fel-Pro on the cylinder head gaskets, but I would go with the ARP cylinder head bolts because they're reusable and can be torqued in the conventional way without messing with the angle gauge and all that. They're also made of exceptionally strong alloy.

OEM lifters are terrific, but when I did my cam swap, I went with Morel 6504 (recently superseded by 7717) drop-in lifters and they're excellent also, but aren't available in an AFM version. Definitely go with OEM on the lifter trays, and OEM pushrods are fine too unless you decide to run a bigger cam. No experience with the Dorman VLOM. Water pump is a no brainer though. If your oil pressure is fine now, I would leave the pump and pickup tube alone, though with that many miles you're probably due for a timing chain tensioner. Take a look at it while you're in there and if it's looking cracked or worn, then you might as well replace the timing set and tensioner. And, if that's the case, THEN you might as well drop the pan and replace the oil pump, too.

All of this said, it looks like you're doing a minimalist job, which is fine, but if you suspect DoD issues as well, why not delete the AFM/DoD system while you're at it? I did a full AFM delete on my 2012 6.2 with a new cam, lifters and a Black Bear tune to make it all run right, and it's fabulous. Besides, once you're into it far enough to pull the heads, you might as well replace everything on the top end, including the cam. The bottom end on these engines is bulletproof.

Alaska is a beautiful place. Lived there for 3 years back in the 90s.

 

[TollKeeper]

Not adding to the thread, just a question.. 4 and 7? One is a left head, one is a right head. So I am just curious if that was a mistype. I am thinking you meant 7 and 5, or 4 and 6?

https://www.autozone.com/diy/repair-guides/escalade-suburban-1500-and-2500-tahoe-yukon-yukon-xl-1500-and-2500-2006-2007-yukon-denali-and-yukon-denali-xl-2005-2006-firing-orders-repair-guide-p-0996b43f80cb1cc9

I am working on a theory for blown head gaskets, and would like to know your exact "blown" locations.

 

[badbaddolemite]

Sorry, yes 4 & 6. Passenger side, center 2 cylinders. I get air into the coolant when either of these are at TDC.

 

[wjburken]

I wouldn’t use a Dorman VLOM. Everything else seems copacetic.

 

[badbaddolemite]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

Our folks on this Forum knowledgeable in the areas that you discuss will chime in.

thank you much. i wont be home tonight to snap any recent pics of the 'hoe, but when i get back to town i will upload some for sure!

 

[badbaddolemite]

Definitely Fel-Pro on the cylinder head gaskets, but I would go with the ARP cylinder head bolts because they're reusable and can be torqued in the conventional way without messing with the angle gauge and all that. They're also made of exceptionally strong alloy.

OEM lifters are terrific, but when I did my cam swap, I went with Morel 6504 (recently superseded by 7717) drop-in lifters and they're excellent also, but aren't available in an AFM version. Definitely go with OEM on the lifter trays, and OEM pushrods are fine too unless you decide to run a bigger cam. No experience with the Dorman VLOM. Water pump is a no brainer though. If your oil pressure is fine now, I would leave the pump and pickup tube alone, though with that many miles you're probably due for a timing chain tensioner. Take a look at it while you're in there and if it's looking cracked or worn, then you might as well replace the timing set and tensioner. And, if that's the case, THEN you might as well drop the pan and replace the oil pump, too.

All of this said, it looks like you're doing a minimalist job, which is fine, but if you suspect DoD issues as well, why not delete the AFM/DoD system while you're at it? I did a full AFM delete on my 2012 6.2 with a new cam, lifters and a Black Bear tune to make it all run right, and it's fabulous. Besides, once you're into it far enough to pull the heads, you might as well replace everything on the top end, including the cam. The bottom end on these engines is bulletproof.

Alaska is a beautiful place. Lived there for 3 years back in the 90s.

thanks much for the info. i would like to say i am towing the line between minimal and heavy top end job. you are right though, if the bottom end is solid, i really should just go with a complete top end. thank you for the ARP head bolt advice, you and the others who have made the recommendation have sold me on them. are there any AFM lifters besides OEM that are any good? rock auto is out and other than a dealer, i wouldn't know where to source. while i love the idea of a delete kit, i really dont have the time and money to put into something more than an OE repair. my biggest concern is downtime between sending back and forth until the tune is complete. i also worry because where i am in alaska has 100F summers and -40F winters. i would think this would screw with some things. truly i want to swap in a non DoD motor, but with parts availability here, that just isnt feasible. frugal me says to just do the head gaskets, whatever lifter was giving me issues, and be done. but i feel like since i have to go down that far, maybe just replacing everything on the top end is the right answer. the vehicle is paid off, and i just rebuilt the whole front end before the HG decided to crap out. it just seems like to get back on the road before winter, a repair rather than an upgrade is in order and then look at maybe a 6.0/6.2 swap or built motor in the future. as you can tell, i am kind of lost lol so i appreciate all the input.

 

[badbaddolemite]

I wouldn’t use a Dorman VLOM. Everything else seems copacetic.

i had heard about an "improved design" VLOM and could only find info on the Dorman being "improved design". does GM make an improved design that cures the OE flaws?