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

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I have owned my 1995 6.5 Diesel K2500 Suburban since new. It has 137,000 miles. I religiously changed oil every 3,000 miles for the past 22 years with Rotella 15W40. One oil change ago I tried the new T6 5W40 synthetic for better cold starts. The truck only gets about 6,000 miles a year. Only mechanical issue in its history was a blown headgasket at 121,000 miles, which occurred four years ago. (A common 6.5 diesel problem) It was caught immediately and shut off before the oil was contaminated.

The oil anaylsis report came back indicating I had over 17 times the lead amount (158 PPM versus 9), and 3 times the tin (9 PPM versus 2) and almost twice the iron (80 PPM versus 43).

Blackstone Labs opinion is that there is a serious problem brewing and were surprised that the engine is still running. It runs beautifully, with good oil pressure (55 PSI) and no knocks or other noises.

I use Optilube XPD fuel lubricant additive and regular diesel fuel.

Could it be that the change to the new synthetic 5W40 is somehow flushing out contaminants that were dormant in the engine all these years? Or is there a real problem brewing?

Just to be sure I sent them a second sample a week later from the same crankcase oil thinking maybe I contaminated it somehow by scooping the sample out of the drain bowl. But even the new sample caught mid stream was still bad: it had a similar result though the bad stuff was down by about 20% due to the addition of a new quart of oil (106 PPM lead, 6 PPM tin, and 63 PPM iron). At that point I changed all the oil to a new fill of syn 5W40 Rotella T6.

Any suggestions? I have been pricing out new 6.5 long blocks just in case...



 
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Your iron numbers are up as well. Lead numbers were high last October and have been going up. With no noise it's surprising. Any smoke out the back ? Have you topped off any oil? PS: just saw that you did.

Hope this works out for you but it does appear ominous.
 
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No smoke other than the standard black soot on heavy acceleration.

I've been a mechanic (I restore old musclecars) for the past 40 years or so and have rebuilt my share of interesting musclecar engines: 426 Hemis, 455HO Pontiacs etc. Sadly, the original GM 6.5 diesels aren't that "rebuildable" as the heads get cracks between the valves (a problem GM knew about and declared it as normal wear and tear in one of their infamous Technical Service Bulletins!) and the blocks were known to get cracks in the webbing. So even if you tried to rebuild one you would have to search for a new block and heads. Thankfully you can buy the brand new 6.5 Optimizer long block which are the ones made for the HUMVEES by AMG/GEP for about $6,800. AMG/GEP took the basic blueprint to the engine and made it beefier everywhere. So that is probably the way I'll go.

Though I wish there was some other non-fatal explanation for the lead/tin/iron discovery.

Here's the old gal. And yes, that is the original paint, too:

 
Originally Posted By: njsteve
No smoke other than the standard black soot on heavy acceleration.

I've been a mechanic (I restore old musclecars) for the past 40 years or so and have rebuilt my share of interesting musclecar engines: 426 Hemis, 455HO Pontiacs etc. Sadly, the original GM 6.5 diesels aren't that "rebuildable" as the heads get cracks between the valves (a problem GM knew about and declared it as normal wear and tear in one of their infamous Technical Service Bulletins!) and the blocks were known to get cracks in the webbing. So even if you tried to rebuild one you would have to search for a new block and heads. Thankfully you can buy the brand new 6.5 Optimizer long block which are the ones made for the HUMVEES by AMG/GEP for about $6,800. AMG/GEP took the basic blueprint to the engine and made it beefier everywhere. So that is probably the way I'll go.

Though I wish there was some other non-fatal explanation for the lead/tin/iron discovery.

Here's the old gal. And yes, that is the original paint, too:




That's a nice looking Suburban
thumbsup2.gif
 
It's possible that fuel additive contains lead. I would stop using it before your next sample date to rule it out unless you're sure it doesn't contain lead. Just a guess.
 
"That's a nice looking Suburban"


Thanks. Ordered it brand new when we lived in Florida, just after my wife and I first got married. When the kids were born, they came home from the hospital in that truck...fast forward a couple decades...and one went to college in it. She graduates next month and I'll bring her home from college in that truck, too. It's a member of the family after all this time so I aim to keep her running for the next college adventure in a year or too. (fingers crossed)
 
Originally Posted By: 901Memphis
It's possible that fuel additive contains lead. I would stop using it before your next sample date to rule it out unless you're sure it doesn't contain lead. Just a guess.


I aksed their engineer that and he said:

"Fuel additives like Optilube don't typically show up in our tests since they get burned up before reaching the oil. When tested by themselves, we still don't typically see anything that shows up in the spectral results."
 
I am not sure I would install a new engine. Even though there is a lot of family history in the vehicle. It's an old vehicle.

Maybe pull the crank and work on it.
 
Just wanna say it is NICE to see a vehicle so well taken care of. Can't help much regarding the oil analysis but hope it's nothing or a simple fix.
 
Just keeping topic going. The iron is from rings? at 137 K, I'd be mad. That isn't much of an engine. Sudden increase in bearing material may indicate a spun bearing. Total wild guess. It is eating a wrist pin bushing. Please post a follow up TIA
 
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Perhaps the question to ask on an oil web site is what oil should one use in this Diesel engine with the given miles and recent questionable used oil report? Would something thicker like Mobil 15W-50 to try to give some extra oil cushion to possible questionable bearings be the best choice, even if the 15W means some slightly harder starts in winter temperatures? Or is this engine probably on its way out regardless of any oil that is ran in it?
 
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You could have a case of "lead streaking" where some iron bit is trapped in a main bearing
and is tearing out extra lead, at some point the iron gets flushed out.

Lead streaking may also lead to high iron numbers too. At the next oil change, take an oil sample,
then add 1 quart kerosene to the oil as the engine idles for 20 minutes, no load, then shut her
down and do an oil and filter change. The idea is kerosene is an engine oil flush, an older trucker trick,
you'll wash out a lot of residual crud you've never seen before, at least I did on a 1980's 318 V8!!

I started using FilterMags on the outside of the spin-on oil filter. Sizes are matched to
filter diameter. I then bought another one, now I run a pair. The iron levels dropped 40%
and the lead dropped with it too. I wish I thought of it decades ago when I used to run
really long distances every year!

Be sure there's 1/2" to 5/8" clearance all they way around your oil filter diameter
if you want to use a pair of FilterMags before buying.

Check out the results and other ideas:

" FILTERMAG vs HOMEBREW "
https://app.box.com/s/uxvu8dmscf5wcgftutdm0ejqwgn86tw7


While this does not address the actual root-cause in your case, at least it reduces it until
you do find the root cause and fix it if it's economic to do so.

In my case I can run 6 months before the oil even starts to darken a little on the dipstick
rather then jet black in 5 weeks!

Post when you find out what it was! Good Luck
 
Either way even if the engine is wearing itself faster there's no reason to replace the engine until it starts giving you oil pressure problems or dies unexpectedly.

My Buick has been spitting lead and copper in uoas for some time now and it's still going, that's with a gold plug, filter mag and Fram ultras.
 
Originally Posted By: Donald
I am not sure I would install a new engine. Even though there is a lot of family history in the vehicle. It's an old vehicle.

Maybe pull the crank and work on it.


The engine has to come out for that, which is the same amount of labor plus the rebuild time. After bearings, new crank, possbly rods, pistons.... you are at 3/4 of the price of the brand new modern version of the 6.5, that is a bolt-in swap. Not even considering the extra cost of a good block (BTW, there are none out there as AMG/GEP doesn't sell the Optimzer block on its own) in the very likely even that stress cracks are found in the main webs.

As for being an old vehicle, well a new Suburban is around $80,000. They don't make the 3/4 ton version any more and I paid $38,000 cash for this truck 22 years ago. Other than tires, fuel, and oil changes and the $2000 head gasket job 4 years ago, it hasn't cost me anything in two decades. So adding $7,000 to that $38K invested 22 years ago amortized over that time period, would be a cost of around $2100 a year.

We keep cars a while in my family. Here's my Grandmother's 1975 Firebird 455 and my Grandfather's 1971 Lincoln Golden Anniversary Continental. Coincidentally, both have 80,000 miles on them. Both of my kids learned how to drive on their Great-Grandmother's Firebird, which is kind of cool. (and they both hate driving the gigantic Suburban).



 
Originally Posted By: Ramblejam
Originally Posted By: njsteve
I have been pricing out new 6.5 long blocks just in case...

Specifically, what have you been looking at? There's an Optimizer 506 (Navistar casting, far superior to GM casting) over on Ted's right now: http://www.ebay.com/itm/6-5-Diesel-Engin...7-/361771362445




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...
 
If your going to keep it, go to The Rust Cop Shop in Dogeville NY and have it sprayed with CarWell. I was there yesterday. I bring all my vehicles there in the spring. Cliff will do a great job.
 
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.

The Optimizer engine is the way to go. The original block and crank were flawed in more than a few ways.

I would not buy any 6.5 engine parts "as-is". You're buying someone else's trash and you know it.

Beautiful 'Burb. Keep it rolling.
 
Originally Posted By: i_hate_autofraud


You could have a case of "lead streaking" where some iron bit is trapped in a main bearing
and is tearing out extra lead, at some point the iron gets flushed out.

Lead streaking may also lead to high iron numbers too. At the next oil change, take an oil sample,
then add 1 quart kerosene to the oil as the engine idles for 20 minutes, no load, then shut her
down and do an oil and filter change. The idea is kerosene is an engine oil flush, an older trucker trick,
you'll wash out a lot of residual crud you've never seen before, at least I did on a 1980's 318 V8!!

I started using FilterMags on the outside of the spin-on oil filter. Sizes are matched to
filter diameter. I then bought another one, now I run a pair. The iron levels dropped 40%
and the lead dropped with it too. I wish I thought of it decades ago when I used to run
really long distances every year!

Be sure there's 1/2" to 5/8" clearance all they way around your oil filter diameter
if you want to use a pair of FilterMags before buying.

Check out the results and other ideas:

" FILTERMAG vs HOMEBREW "
https://app.box.com/s/uxvu8dmscf5wcgftutdm0ejqwgn86tw7


While this does not address the actual root-cause in your case, at least it reduces it until
you do find the root cause and fix it if it's economic to do so.

In my case I can run 6 months before the oil even starts to darken a little on the dipstick
rather then jet black in 5 weeks!

Post when you find out what it was! Good Luck


He has been changing his diesel oil every 3k miles! There is not going to be anything to flush out! This thing will be spotless inside. Definitely no kerosene required.


Originally Posted By: Donald
I am not sure I would install a new engine. Even though there is a lot of family history in the vehicle. It's an old vehicle.

Maybe pull the crank and work on it.



Why not? Are you all worried about it's value or worth? If so, that's pretty subjective. He doesn't sound like he's going to ever get rid of it. So if it's in good shape (it is) and meets his needs (it sounds like it does) then it's a heck of a lot cheaper than dropping 30-70k on a new or newer burb. Now if he were planning on selling or trading then yeah, he'd never recover the price of the engine and he should probably stop while he's ahead.

Sorry for the rant OP, but it annoys me when people tell others to just get rid of a vehicle because of it's age or supposed worth. It's as if so many people just assume a vehicle will be or needs to traded and that there is some arbitrary cut off on how much you can put into it. What no one seems to realize is that if you're driving it to it's grave, it's value or worth on the market means zilch! It's always "This thing is only worth X dollars, so you should only put Y into it or get rid of it!" So you're telling me I need to buy a vehicle worth many, many thousands, that way it's "worth" enough to repair? Screw that! So in the OP's case which is cheaper for something that does what he needs? Let's see... 6500.00 for an engine or 65,000.00 for a new suburban. Hmmmm.... let me think?
 
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