GM 6.5L; Rotella T6 5w-40; bearing problems?

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Thanks for the moral support.
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It's a great running truck. Chevy/GMC hasn't made a diesel Suburban since 1999 and stopped making the heavy duty 3/4 ton with the last generation that ended a couple years ago. So you can't really tow a car trailer with them any more.

We are keeping it forever so I have no issue putting money into it to keep it going. I just drove it 100 miles this morning to buy some old R12 Freon for one of my old cars. Great oil pressure, no non-diesel suspicious noises, no issues (knock on wood).

I cruised through the local Chevy truck dealer yesterday just for giggles. All the truck salesmen were looking and pointing at the Suburban as I idled by the windows. Afterwards I cruised by the line of new Suburbans they had there - all in varying shades of ugly, dark, metallic mud or charcoal colored. (Doesn't anybody make an actual pleasant paint color any more? The lowest sticker price I saw was $76,000 - exactly double what I paid for mine 22 years ago.

When we had the headgaskets done three and half years ago (I had a local diesel truck mechanic do it at the time, who specialized in 6.5s), he was astonished on how spotless the inside of the engine was when he pulled the valve covers. This was due to the constant oil changes.

I have a feeling we may not have caught the initial headgasket failure in time 15,000 miles ago - it most likely "steam cleaned" that cylinder of oil while it was running and hurt the rings and maybe a bearing or two. The 6.5s were notorious for the rearmost cylinders running hot and blowing the headgaskets, which is exactly what happened to this engine: cylinder #7 blew out the metal ring in the headgasket. And right where they blow out is the drain port for the engine oil from the cylinder head into the block. It was a weak point in the engine design that has been remedied in the Optimizer blocks.
 
Originally Posted By: DoubleWasp
I would not touch the engine until death. Got one engine that's been tossing high wear metals for 20k miles. We just put whatever cheap thick oil we have and keep running it.



What are the high readings on that one? Anything like mine?
 
Originally Posted By: njsteve
Teds are the center mount (intake manifold mounted) turbo application which uses cylinder heads with a different bolt angle than the GM/Chevy truck cylinder heads with the side mounted turbo. One of my diesel cohorts recently installed one and it turned out to be a defective unit. As they are sold "as-is" he did not get any money back from Ted's. So, If I got a Ted's take out I would still have to rebuild it and spend a couple grand for fully prepped modern cylinder heads...

Just figured if you're going through the trouble of a transplant, you'd want to make it a little more lively and durable (HX40, o-ring/stud, etc.) while everything is apart.

Has your cohort documented what occurred on a forum/online anywhere? Even if a bad item did make it past their testing process, from what I understand, they'll make it right within reason (as witness to that, they have 3,883 reviews on eBay with 100% positive feedback).
 
Yes he did on the 6.5 website: http://www.dieselplace.com/forum/63-gm-d...dy-install.html

The engine had weird internal noises. It took a while to get it installed, he spent a lot of time troubleshooting. He couldnt get anyone from Ted's to return his emails/calls. It turned out that Teds had problems getting back to him due to health issues of several of their people there. Once the dust settled, they refused to help him out with the engine. He ended up trading the truck in after all that work.
 
First, quit using the additives; this will reduce variables. I am not saying this is bad for it; just looking to reduce as many input changes as possible.
Next - change back to dino 15w-40. You don't need T6 in your area. Again- reduce the variables. I seriously doubt it was "cleaning" out other stuff that the dino left behind; there isn't that much difference in VOAs to warrant a huge increase in metals in terms of "cleaning" the engine.
It's very likely you've spun a bearing, or have a large particle streak shedding material.


I would recommend you continue to operate it, until a major issue surfaces in a manner which would cause reliability concerns. The only caveat is to not get too far from home; don't want to be 1000 miles away on a vacation when the engine dies.

You can rebuild this engine, but I completely agree that a new 6.5L is a better option. And that is FAR cheaper than getting a new rig. Seems the rest of your 'Burb is in great shape, and it's a model combo (diesel, 3/4 ton) you cannot even get anymore. Nothing wrong with updating the old girl with a transplant!


BTW - I just about dropped over after seeing your Continental! I am SOOOOO jealous! I had one (white) just like that when I was growing up, and into my college years. It was in my family for a few decades. My dad got it used; we used it to pull our RV on trips. That thing is a BEAST! I surely miss that old car. '71 high-comp 460 4bbl; 360hp; 500 ft-lb of grunt. 3.00 rear. While not able to leap off the line (5500 pounds) it would haul the mail with serious expediency on the highway. And that trunk! You could pitch a 4-man tent inside of it. Ahhhhhh - those were the days ...
 
That Lincoln was my grandfather's "gold watch" when he retired. Here's the back story: http://www.yenko.net/forum/showthread.php?t=123890

We are actually taking the 'burb on vacation later this summer and then I have a car show to trailer my SD455 to... so I think it is time to start the new engine purchase process. And if I pull the old engine and find that it was good after all, I can always sell it to another diesel fan as a running rebuildable engine with a known history from day one.
 
I figure I'd give you guys and gals an update. The third oil analysis 750 miles later showed the same high levels of lead and tin. I ended up ordering a brand new upgraded 6.5 diesel engine off the AM/GEP (HUMVEE) assembly line and after nine weeks it was delivered. I just installed it last week. It took nine days to pull the old engine, swap parts over and get the new one in and running. Quite the fun process. Here's the final oil analysis from Blackstone:
 
And to show what how accurate the oil analysis actually was, here are some choice photos of the connecting rod and main bearings from the engine. Major flaking visible for the outer bearing material. I am glad I pulled the engine. It also turned out that the block was cracked in all the main webs emanating from the main bolt holes. This is a common malady of these engine due to manufacturing issues back in the day and the machining of the blocks while they were still "green". The new AM/GEP 6.5 engines are a total redesign of the GM blueprint and they have none of the original issues. The new engine runs great!








 
Good job! I think you made the right choice in repowering with the updated engine. You still have a low mileage vehicle and with a fresh engine, you should be set for a long time. Does that new engine get you some extra HP/Torque?

I used to help tear down some heavy duty diesels and I don't recall ever seeing bearings that bad with over a million miles on them, although I was young and that was 20+ years ago, so I may be wrong. Thanks for the update and pictures.
 
Yup, this engine with forged crank, rods, and coated pistons and the upgraded cylinder heads, (and with the lower 18 to 1 instead of 22 to 1 compression) is capable of 300+ horsepower and close to 500 lbft when properly tuned. (compare that to the stock 190 horse rating). I already have the Heath aftermarket tune (this is an OBD1 system so it actually has the old style "chip" that was upgraded by Heath Diesel). I installed the 2-1/2" mandrel-bent crossover pipe and 4" down pipe to 4" exhaust. Added the K47 cylindrical air filter box from a 99 and the truck is probably pushing a good 250 horsepower now at 11 psi boost. It sure accelerates nicely and the power is really noticeable above 60 mph.
 
Very nice! Thanks for the pictures and great to see that beauty is back on the road!

As well its nice to see that the UOA are accurate and pointed you in the right direction.
 
That's excellent, it's rare on this forum that an engine with bad analysis results is actually taken apart and the results corroborated.

Kudos NJSteve!
 
I love this thread. I came back and read it again.

I nominate this for BITOG Classics, not that said forum currently exists, but if it did, I would want to see it there.
 
Originally Posted By: njsteve
Originally Posted By: DoubleWasp
I would not touch the engine until death. Got one engine that's been tossing high wear metals for 20k miles. We just put whatever cheap thick oil we have and keep running it.



What are the high readings on that one? Anything like mine?


Worse. It's sort of tapered off, but the worst report had 268ppm lead. Rattles like a belching robot under acceleration. There's a bearing gone for sure. It just keeps kicking, so we keep running it.
 
Thanks. We took the truck on vacation last week to the Adirondacks. It ran flawlessly. 1,200 mile round trip fully loaded with 4 adults, 1 dog, and assorted luggage. Got 18.3 mpg highway- a 22 year best mpg record for this truck given that it is a 8600 lb. GVW, 4WD with 4.10 gears. I just changed the oil and sent a sample off to Blackstone. I will update in a week when the baseline results come back.

I can't imagine anyone abandoning a vintage truck like this and then spending ten times the cost of this new engine to buy a brand new 2017 Suburban when they don't even make a 3/4 ton version any more, or offer a diesel engine.

 
Originally Posted By: Chris142
Would you consider putting a gas engine in it next time?


No. Never even considered it. You may get more horsepower with a big block Chevy engine but the fuel mileage would be much worse. You'd also have to change over so much other stuff, including the transmission, that in the end it would have cost more that the "simple" unbolt and bolt-in the same design 6.5 diesel.

And I do like the angry rattle of this old diesel design. Whenever I drive it into town, my local mechanic buddy always knows I am in the area. He always tells me that he can hear the distinctive engine sound whenever the truck enters the local traffic circle two blocks away. With the free-flowing, 3-inch DiamondEye exhaust, it is definitely a loud truck under power.
 
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