2012 Yukon Denali 6L80 Issues/Advice

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wsteele

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Yeah, I'm not messing with the oil issues myself; I don't particularly trust this shop but they're right across the street from me and I was curious what they had to say, in which they did say my rear main seal was bad (that's odd bc I had it replaced last week) LOL.

My trans guy said he thought it would be easier to get to those other leaking gaskets saving me some cash. They're saying it's the same amount of work regardless...
I am having a hard time understanding what each party is saying to you exactly.

The pan gasket doesn’t entail removing the transmission, the rear main seal does. It made total sense the transmission guy did your rear main seal, maybe a 20 minute job once the transmission is out.

If the shop across the street says your rear main seal is leaking, it may be a defective gasket or was installed improperly. As far as it being the same work regardless of which gasket was leaking, that makes no sense.

I would seek out a highly rated independent shop and start using them for your trucks maintenance. Once you have confidence in the shop you use, all this stuff becomes very easy to analyze. If you dont have confidence in the shop you use, it will drive you crazy.
 
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Geotrash

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Regarding the rear main seal. If my transmission guy replaced it and it's still leaking due to the gasket not being replaced. Was that job all for nothing? In other words is the location of the pan gasket just as much as labor intensive as the rear main seal meaning it's a pain to get to on an AWD?

My tranny guy wanted nothing to do with the oil leak...simply a favor while he was in the transmission (didn't charge me).
It sounds like there was an oil leak before the transmission guy replaced the rear main seal that was unrelated. If so, then it makes sense that you still have the leak but the second shop should be able to tell where it's coming from and I doubt it's the rear main seal. Transmission guys do those all the time and are unlikely to mess it up.

It could be the oil pan gasket, but I'll bet it's the gasket for the oil cooler block-off plate on the driver's side just above the oil pan and just forward of the transmission bell housing.

If it's the oil pan gasket, it's a PITA to replace because you have to drop the frame crossmember, and lower the steering rack and front diff to get to it. It takes me 2-3 hours to R&R the oil pan laying on my back and I've done it 3 times now (long story). If it's the block-off plate gasket (more common), it's a 20 minute job.
 
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You guys are great and KNOW your stuff - This has been VERY HELPFUL and much appreciated!

I'll save my rant but this morning I went to my independent shop that has a great mechanic but we have a language barrier. Long story short I was able to talk to him (the mechanic) before the owner got there and he confirmed (by really looking up in the oil pan) that the Rear Main Seal was good. Where's the oil leak? I THINK the consensus is the oil pan gasket.

That said and this might be for another thread but the biggest issue I'm having right now is replacing the front end components:

Shop One Quote (I don't trust them)

Labor: @ 6hrs

"Remove and replace front driver and passenger side strut assembly w/passenger side CV axle, sway bar links, and lower ball joints"

Parts:

Lower ball joint (2) = $231.10
Sway bar link or kit (2) = $69.72
Front complete Strut Assembly: (2) = 333.16
New CV Complete Assembly (1) = 148.50

Total = $1,412.48

The other shop from this morning (I trust them more but not sure about where/how they're getting parts) wanted to add lower A arms and called their parts place:

With lower A Arms and all parts listed above parts alone were ~ $1,500

Out the door for $2,000.00


Forgive me but someone posted on this thread that i could get moog parts and if really ambitious could knock it out myself.

If I can acquire the parts I can have my guys across the street install for labor only but no warranty.....
 

swathdiver

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You guys are great and KNOW your stuff - This has been VERY HELPFUL and much appreciated!

I'll save my rant but this morning I went to my independent shop that has a great mechanic but we have a language barrier. Long story short I was able to talk to him (the mechanic) before the owner got there and he confirmed (by really looking up in the oil pan) that the Rear Main Seal was good. Where's the oil leak? I THINK the consensus is the oil pan gasket.

That said and this might be for another thread but the biggest issue I'm having right now is replacing the front end components:

Shop One Quote (I don't trust them)

Labor: @ 6hrs

"Remove and replace front driver and passenger side strut assembly w/passenger side CV axle, sway bar links, and lower ball joints"

Parts:

Lower ball joint (2) = $231.10
Sway bar link or kit (2) = $69.72
Front complete Strut Assembly: (2) = 333.16
New CV Complete Assembly (1) = 148.50

Total = $1,412.48

The other shop from this morning (I trust them more but not sure about where/how they're getting parts) wanted to add lower A arms and called their parts place:

With lower A Arms and all parts listed above parts alone were ~ $1,500

Out the door for $2,000.00


Forgive me but someone posted on this thread that i could get moog parts and if really ambitious could knock it out myself.

If I can acquire the parts I can have my guys across the street install for labor only but no warranty.....
Is this truck a keeper or are you getting rid of it soon? Those prices are certainly not GM OE and may not all be Moog or Monroe either.

Two whole struts assemblies for $333? Mine each cost me about $300 to build myself with GM OE parts. A new GM OE CV Axle is about $300.

It's not a big deal to drop the front differential and get it out of the way. My two teenage daughters did it in our driveway and I crawled down there to lift it back up when we were done.
 
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Pointer 21

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Is this truck a keeper or are you getting rid of it soon? Those prices are certainly not GM OE and may not all be Moog or Monroe either.

Two whole struts assemblies for $333? Mine each cost me about $300 to build myself with GM OE parts. A new GM OE CV Axle is about $300.

It's not a big deal to drop the front differential and get it out of the way. My two teenage daughters did it in our driveway and I crawled down there to lift it back up when we were done.

Keeper or getting rid of soon....I'll be in it for another year at least (was hoping). The way these bills are racking up I'm wondering if I should've gone another direction.
They pointed out that my rear shocks were toast as we were wrapping up. FACEPLANT.

Right now I'm down $3300 on the transmission (such is life). The front end looks so bad that I'm scared to drive to the store, much less out of town for work.

I don't know how far to jump in on this front end. That quote (I'd think) would be the closet to the Stealership. Just need to find a happy medium I suppose.


Few quick pics I snagged this AM while under the truck.
 

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Geotrash

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Those sway bar links are super easy to replace, as are the rear air shocks and compressor. With shocks that bad, the compressor is almost certainly toast. The Dorman compressor is quite good for an aftermarket unit, and I bought new OEM rear air shocks on Rock Auto for $25 each.

That said, I see nothing wrong with either CV joint - no torn boots. Are you sure there's anything wrong with any of it? Did you lift either front corner and check for play on the ball joints? It could be much ado about not much.

That underside looks clean. Once you get all of that stuff replaced, I'm sure someone on here will buy it from you :)
 

swathdiver

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Keeper or getting rid of soon....I'll be in it for another year at least (was hoping). The way these bills are racking up I'm wondering if I should've gone another direction.
They pointed out that my rear shocks were toast as we were wrapping up. FACEPLANT.

Right now I'm down $3300 on the transmission (such is life). The front end looks so bad that I'm scared to drive to the store, much less out of town for work.

I don't know how far to jump in on this front end. That quote (I'd think) would be the closet to the Stealership. Just need to find a happy medium I suppose.


Few quick pics I snagged this AM while under the truck.

Well, look at it this way, for what you spend on these repairs, you're still ahead of buying a new truck and without the big payments.

This 1500 chassis seem to need overhauling at about 150K or so, some parts sooner, some later, but we know these things now because of the participation by the members of this forum. I spent a lot of money on my truck this year too, no regrets at all because she's a keeper.

The shops want your business, missing sway bar bushings and worn out shocks are not critical safety items. The ball joints could be depending on how much play there is.

If you have a place to work on it and some tools, you can do it yourself. If my girls can do the work with my direction, so can you with the help of this forum.
 
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Those sway bar links are super easy to replace, as are the rear air shocks and compressor. With shocks that bad, the compressor is almost certainly toast. The Dorman compressor is quite good for an aftermarket unit, and I bought new OEM rear air shocks on Rock Auto for $25 each.

That said, I see nothing wrong with either CV joint - no torn boots. Are you sure there's anything wrong with any of it? Did you lift either front corner and check for play on the ball joints? It could be much ado about not much.

That underside looks clean. Once you get all of that stuff replaced, I'm sure someone on here will buy it from you :)
You're reconfirming what my guys I trust were saying (they don't have a fancy quote system for me to post); however, they said the CV joints did not need replacing but did recommend doing the lower A arms. When he was calling for parts it came out to about $1500 for all parts including the CV joints ($150/piece) so we can subtract $300 there.

I didn't get a straight answer on what parts he was using which is why I was thinking of ordering my own OR walking up with my list and saying get these....we discussed MOOG parts but this was all on the fly. Again this shop isn't fancy AT ALL but I do believe they're honest (and within walking distance to the house).
 
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Well, look at it this way, for what you spend on these repairs, you're still ahead of buying a new truck and without the big payments.

This 1500 chassis seem to need overhauling at about 150K or so, some parts sooner, some later, but we know these things now because of the participation by the members of this forum. I spent a lot of money on my truck this year too, no regrets at all because she's a keeper.

The shops want your business, missing sway bar bushings and worn out shocks are not critical safety items. The ball joints could be depending on how much play there is.

If you have a place to work on it and some tools, you can do it yourself. If my girls can do the work with my direction, so can you with the help of this forum.
Totally agree!! Why it all happened at once is just well...one of those things I guess. I HATE dealing with the jokers though. My broken up spanglish was well understood when I bent over and said "Too mas dinero"......ALL in good fun. Just want to make sure I'm going the right direction. My council here is making me wise!


Please note that there are DEFINTELY problems with the ball joints. I have a major crack in my driveway (another story) thats tearing the passenger side up and I also am frequently at the ranch doing everything except driving like MS. Daisy!

Guess I need to work on a materials list and get to work!
 
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swathdiver

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Guess I need to work on a materials list and get to work!

www.gmpartsdirect.com

www.gmpartsgiant.com

1632957412155.png

Use your VIN with those links above to see if the parts you want are the same as mine, many will not be the same as you have a Denali with the nicer riding suspension. For the most part, these are all GM OE parts. Some are ACDelco Professional and you can use these numbers to find the ACDelco Professional and Moog CK Series parts which are far superior to their RK Series. With regards to the control arms, the ACDelco Professional are the exact same part as the Moog CK series.

The upper control arm's ball joint is not serviced separately, you replace the whole arm. Most of us also replace the lower control arm in lieu of just doing the ball joint so we get new suspension bushings which by this age are beginning to crack and dry rot.

While I'm not a fan of those pre-assembled strut assemblies after lots of research, some folks on here have used them and are happy with them. I believe they used ACDelco and Monroe but cannot remember for sure.
 

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