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Sierra 3.0

Brand New GMC 3.0 with bad oil leak

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Sorry, I guess I misunderstood. Let's try oil cooler?

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Sorry, I guess I misunderstood. Let's try oil cooler?

Sent from my SM-N950U using Tapatalk


Oh that makes more sense. Leaking from drivers side?

Sent from my SM-N975U using Tapatalk

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I found my leak on a 2021 on the drivers side thought the filter was loose tried tightening and then I realized the gasket/seal from the oil filter adapter to the engine block was leaking. Here’s a video of it. Also found a seal for the trans line installed incorrectly. 

 

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From what I understand there is a company in Flint, Michigan doing quality control checks on the raw 3.0L castings and they are scraping out a lot of faulty castings.

Something to do with the rear oil seal area.

These are raw castings from Mexico and haven't had the final machine work done.

My theory is, some faulty ones are getting through and the rear oil seal isn't sealing as it should after the final machining.

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So guys have a 2020 at4 3.0l diesel and just went to drive it this morning and seen about 3 quarts

On the garage floor so pissed. Need to get it towed in to the dealer. Any ideas what's wrong only 7660. Just about over gm trucks

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On 1/9/2021 at 11:46 AM, Bmf007 said:

So guys have a 2020 at4 3.0l diesel and just went to drive it this morning and seen about 3 quarts

On the garage floor so pissed. Need to get it towed in to the dealer. Any ideas what's wrong only 7660. Just about over gm trucks

Ouch that is a rough one, sorry to see you having trouble like this. 

 

Reading here it seems some blocks have defects with the machining of the block, not saying that's the issues but these engines have such a small sample size right now it will be tough to get much info on them outside of the dealer techs. That is part of the game these days, you are essentially a beta tester for gm, paying one at that, not saying they didn't do their due diligence in the engineering of this engine but teething & growing pains with the amount of crap that is put on these engines is bound to happen.

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I wanted to add my experience to the above info.  I have a 2020 Silverado RST 3.0 Duramax with 11,000 miles.  I have had no issues since I bought it new until last week.  Truck went into limp mode and CEL came on.  Took to dealer and they found the rear main seal was leaking and are still working on it.  

My concern is that if the machining is faulty, won't the issue just happen again?  The dealer is going to fix the leak but I am sure that doesn't involve machining work does it?

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On 2/22/2021 at 9:27 PM, wadecool said:

I wanted to add my experience to the above info.  I have a 2020 Silverado RST 3.0 Duramax with 11,000 miles.  I have had no issues since I bought it new until last week.  Truck went into limp mode and CEL came on.  Took to dealer and they found the rear main seal was leaking and are still working on it.  

My concern is that if the machining is faulty, won't the issue just happen again?  The dealer is going to fix the leak but I am sure that doesn't involve machining work does it?

Yes it will more then likely leak again if the block casting is faulty and they try and band aid fix it with another seal. I would fear some pile of you know what bulletin trying to force dealers to goop the seal and hope it holds. Much like the window issue on these trucks, dont fix the cause, just apply copious amounts of sealant to see if they can plug the leak.

Edited by BIGDOGx

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yeah they dont just hand out new replacement trucks like gumball machine......even at times when they should!.....just hope the issue is small and can be fixed without too much drama.....so far have been really lucky with new vehicles but never know....

 

if a new one had a huge issue i would have a kiniption fit that i do know...and wouldnt stop until i found the person who said "YES"

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