First post- 15 Yukon Denali w/150K catastrophic engine damage-

[Ibustbravo]

Hi Everyone,

This looks like an active forum! If you were having a bad day, hopefully my story of woe will make you feel better about your problems.

This past Tuesday the engine in my Yukon blew up, literally. I pulled the spark plug on #2 and it was flattened and difficult to get out. Upon further inspection with a bore scope..... Total carnage... The cyl is destroyed, it's been smashed to bits by the connecting rod, bits are caught in the crank and the block is damaged. I can't even turn the engine over to get it out. haha.. holy cow! This is going to get expensive.


Just for reference, It had 149K miles.. 4393 hours on the hobbs meter with 980 idle hours. The DOD was turned off via HP tuners.. I still owe $$ on it..

I'm kicking around installing a 5.3, they're 1/2 the cost.. I can get a 5.3 firmware and just flash the ECU with it as a starting point. I don't know, what do you guys think? Stick with the 6.2 or go with the smaller, cheaper 5.3?

 

[OR VietVet]

Welcome to the forum and the world of opinions about your engine choices. Gonna sit back and watch this for sure:

 

[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.

If it were me, if the rest of the truck is in good shape, I'd pay the extra and go for the 6.2. There will be less 'adjustment' of existing systems to accommodate a different motor. And, once you have the 6.2, going to the 5.3 is going to be a letdown, IMO.

 

[Tonyv__]

If you just want my opinion. I also think the downgrade from 6.2 to 5.3 will be a major disappointment.

However I do know we’re not all made out of money and I’m not 100% sure what I would do if my 6.2 shit the bed.

 

[CMoore711]

I'd stick with the 6.2. These are some reasons that come to mind.

1. Puts it back to OEM spec with same motor.
2. If you put a 5.3 in it you'll raise more questions and cause more concern than it's worth if/when you ever go to sell or trade in.
3. If you put a 5.3 in it a dealer may not even take it on trade in since they would consider it an "engine swap".
4. There's probably a lot more electrical nuances and changes necessary to make the 5.3 work, that I'm sure will be "discovered" during the install. Which wouldn't be fun.

So far where have you looked/shopped for a new L86 6.2 motor?
Are the heads still good? Reusable?

Your vehicle overall has 149K on it; Who says the replacement L86 6.2 has to be brand new? I'm sure you could find a lightly used one with 10K-30K ish miles +/- and save some money that way?

I think bigger picture answers to questions like these would help steer you in the right direction and narrow down your options:

How much longer do you plan on keeping and using the vehicle?
Do you plan to just replace the engine and sell / trade in shortly after?
Do you have a method of transportation now while your Denali is down?

 

[Ibustbravo]

Thanks for the warm welcome guys. I appreciate the back and forth. Here's some pics of the truck. This will be back to back engines. I finished up my F350's 6.0 this past spring. That was a big job. This doesn't seem to be as much work but we'll see.

This engine is mechanically locked up so I'm pretty sure I'll have to pull the passenger side head to fish out parts and rotate the engine. Below is what came out of the intake plenum, that's not even all of it.

Anyways, to answer some of your questions, yes I plan on keeping the Yukon. I'm kinda married to it now. I'm not going to do the 5.3.. I wouldn't be able to look at myself in the mirror. I like the power and I bought this truck for the 6.2 engine.. I have not been disappointed.


My wife was driving and says she didn't hear a thing.

 

[Brewder]

"My wife was driving and says she didn't hear a thing."

Sorry for your loss but that quote made me laugh.. and we might be married to the same woman.

 

[Geotrash]

Thanks for the warm welcome guys. I appreciate the back and forth. Here's some pics of the truck. This will be back to back engines. I finished up my F350's 6.0 this past spring. That was a big job. This doesn't seem to be as much work but we'll see.

This engine is mechanically locked up so I'm pretty sure I'll have to pull the passenger side head to fish out parts and rotate the engine. Below is what came out of the intake plenum, that's not even all of it.

Anyways, to answer some of your questions, yes I plan on keeping the Yukon. I'm kinda married to it now. I'm not going to do the 5.3.. I wouldn't be able to look at myself in the mirror. I like the power and I bought this truck for the 6.2 engine.. I have not been disappointed.


My wife was driving and says she didn't hear a thing.


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Good call on going back in with a 6.2. Bummer that that happened.

Were you by chance running 87 octane most of the time in that thing? That’s a fairly common failure for people running 87 in their 6.2’s. I’ve never heard of it happening to one running premium, but there’s a first time for everything.

 

[B-train]

I like the wife quip as well......heard similar over the years. But, with patience and practice you can get them to come around. LOL

Also, I love that you are doing it in the street of your nice neighborhood. Feels like something I would've done......then get looked at weird for being blue collar. Good stuff