2012 GMC Yukon Denali XL: oil leak discovered

jyi786

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First, I got stranded last week. Both batteries and starter was changed. See this thread.

Now, I just discovered that my truck is leaking oil. Can't say it's BAD, but it's concerning. Small puddles underneath the truck in the morning. Went underneath, and see oil dripping towards the front of the engine, all over the rack and pinion and front cross member.

Any ideas/thoughts on what might be leaking? Not looking to do a lot of work myself unless it's an easy job, as circumstances have changed, and I believe I got my spine re-injured this past week or so. I'm not in physical condition for crazy laborious jobs on my truck. Definitely not going to be taking it back to a dealer, either.
 

Geotrash

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First, I got stranded last week. Both batteries and starter was changed. See this thread.

Now, I just discovered that my truck is leaking oil. Can't say it's BAD, but it's concerning. Small puddles underneath the truck in the morning. Went underneath, and see oil dripping towards the front of the engine, all over the rack and pinion and front cross member.

Any ideas/thoughts on what might be leaking? Not looking to do a lot of work myself unless it's an easy job, as circumstances have changed, and I believe I got my spine re-injured this past week or so. I'm not in physical condition for crazy laborious jobs on my truck. Definitely not going to be taking it back to a dealer, either.
Sorry you’re having some headaches. And sometimes it feels like it all lines up at once, and then you’ll go months and years without a problem.

In this case, check your oil cooler lines. They come out beside the front of the engine on the driver side, and go into the side of the radiator. They are notorious for developing leaks where the metal line is crimped to the rubber hose.
 

jyi786

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Sorry you’re having some headaches. And sometimes it feels like it all lines up at once, and then you’ll go months and years without a problem.

In this case, check your oil cooler lines. They come out beside the front of the engine on the driver side, and go into the side of the radiator. They are notorious for developing leaks where the metal line is crimped to the rubber hose.
Thanks for the assist. When you say oil cooler lines, did you mean the transmission oil cooler lines, like shown in this video?

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jyi786

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Engine oil cooler lines. They run on drivers side into the radiator side tank.

Trans cooler lines run on passenger side.
Ok, so more like this one then:

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Pretty much. They attach to the motor near the oil filter and run up to the radiator side tank. They transition from metal tubing to rubber hose for a bit (for flexibility between moving engine and non-moving radiator) and tend to leak at this crimp. This area can easily be seen from above when looking down under the hood. They're between motor and radiator on drivers side
 

Geotrash

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What Tom said. Usually they just seep, but I've seen them dripping oil as well in the later stages of their useful life. Another common possibility for an oil leak is where the oil cooler lines mount to the engine just above the oil pan. The gasket can start leaking as the seals age. It would be worth your time to crawl under the thing on ramps and get a good look at where the oil is coming from. Armed with that info, we can guide you better.

Also, sorry to hear about your spine injury. I've had good luck finding trustworthy local shops by using the reviews in Google Maps. One good thing about having one of these trucks is everyone and their sister knows how to work on them. I do 90% of my own work but farm out the stuff I don't have time for or feel like dealing with.
 

jyi786

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Thanks all. After a bunch of research, I discovered and concluded that doing ANYTHING oil related, whether it's replacing the oil pan gasket or replacing the oil cooler lines, is going to be a very difficult job. I pretty much have no choice but to take this to either a shop or a dealer to get the work done.

What is a good, competent price I should expect to pay for this? I'd like to take it to a shop, but honestly, I almost feel like I don't want anyone to touch this but a dealer, because it will at a minimum involve dropping the front diff.

Thoughts?
 

wsteele

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Thanks all. After a bunch of research, I discovered and concluded that doing ANYTHING oil related, whether it's replacing the oil pan gasket or replacing the oil cooler lines, is going to be a very difficult job. I pretty much have no choice but to take this to either a shop or a dealer to get the work done.

What is a good, competent price I should expect to pay for this? I'd like to take it to a shop, but honestly, I almost feel like I don't want anyone to touch this but a dealer, because it will at a minimum involve dropping the front diff.

Thoughts?
Any competent indépendant shop can accomplish these jobs no problems at all. I would assure they were using OE parts (not professional line, etc.), but any ASE certified tech with more than 5 years experience can get this done without any drama. As far as pricing, that is dependent on many variables. Th only invariable part of this answer is almost 100% of the opinions on pricing you get here will be low. :)

Focus on finding a really highly (loved) independent shop near you and take to to them.
 

jyi786

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Update: oil leak fixed.

I had initially suspected it was the oil cooler lines. This turned out to be true. They were replaced, along with the power steering pump, which actually was starting to whine and was badly rusted at the bottom. Had the shop change it while they were at it.
 
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