ShadowsPapa

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I think you're right about the 6 quart situation. Maybe those engines got more than six quarts? I just can't wrap my head around what would cause two Gladiators to end up at the same dealer with kicked rods. The only consistency I can think of is getting their oil changed at the same dealer.
Hmmmmmmm........

This will be interesting, but I prefer interesting topics that are not destructive, that don't rely on blown engines....



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DAVECS1

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Especially curious since these have been used in their current versions (physically, that is) since what, 2015? (meaning with VVT, VVL) We've had these in 2 Grand Cherokees and there's hundreds of thousands of them around.
Agreed but it is obvious this control that has done great on all of the applications it has been applied to is now having an issue covering a corner case in the Gladiator. Weather it is the new vacuum pump, engine mounts, cooled Egr, aggressive VVT, new advantek axles, aero dynamics, who knows but, it would be interesting to see the datalog before it gave way. I bet a c-note it was bouncing from negative to positive timing.
 

ShadowsPapa

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Agreed but it is obvious this control that has done great on all of the applications it has been applied to is now having an issue covering a corner case in the Gladiator. Weather it is the new vacuum pump, engine mounts, cooled Egr, aggressive VVT, new advantek axles, aero dynamics, who knows but, it would be interesting to see the datalog before it gave way. I bet a c-note it was bouncing from negative to positive timing.
It's the control - PCM, programming, that's really changed. Otherwise the physical engine is mostly the same. That's what gets me - physically, it's not changed much, especially in the last 4 or 5 years. Programming, the PCM control over things - big change.

Negative timing? ATDC? Never have seen one that fires ATDC. That's going to run HOT and have crap for power. Peak combustion pressures must be 14-16 degrees ATDC or you start pushing on a piston still coming up (if fired too soon before TDC) or totally waste the charge if the peak pressure is after 14-16 ATDC. I can't see these running SLOW enough and burning FAST enough to be able to light the charge ATDC.
If it was needing later timing but fired way too soon, damaged can be done, perhaps that's something that could be going on. I've heard of some folks complaining of "ping", detonation, and these should be immune to that if everything works properly.
 

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Don't you mean a rod through the block? The piston is aluminum, large, in a cylinder surrounded by coolant, and then the walls of the block around that. It would have to shoot to the side - pistons go up and down. The piston would be blocked upward by the head, downward by the crankshaft - which would shred the piston.
A rod - yeah, that I could see. They break and go sideways out the side of the block. Best example I saw was a 232 (father of the 258) with a rod that opened up a fair crack in the side of the block. The couple finished driving it back to Iowa from the middle of Nebraska on 5 cylinders that way.

As far as foaming oil - windage, they call it - when the wind caused by the crank throws aerates the oil, foams it. You lose oil pressure when that happens. You also have trouble with the lifters and other things dependent on oil pressure.
There's a lot of these that have had 6 quarts put in them, there's even a couple of TSBs out there on the topic. If 6 quarts were to cause this sort of damage, I'd expect to see a lot more of this sort of thing. And the extreme angles these run - hmmmm, I sort of doubt that was the cause.
Ha! so right you are. Pistons usually end up with a hole, or grenaded, but never saw one through the block..... just symantecs anyway, we knew what he meant
 

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I think you're right about the 6 quart situation. Maybe those engines got more than six quarts? I just can't wrap my head around what would cause two Gladiators to end up at the same dealer with kicked rods. The only consistency I can think of is getting their oil changed at the same dealer.
Someone - Not that dealer obviously - needs to do root cause analysis. Of course we will never hear anything about it.....
 

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Almost has to be. Did they need more clearance for greater articulation, other parts under there, perhaps? Or find 6 simply wasn't necessary any more?
I never quite got the 6 quart bit anyway when heavier duty engines run 5 just fine.
Except for AMC v8 s . lol , at prolonged high rpm .
 

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Except for AMC v8 s . lol , at prolonged high rpm .
Well, there are tricks for that as well......... to let the oil back to the pan more quickly. I run a thinner oil and have almost no issue that way now.
My 390 - I ran 5.5 quarts. I should have opened up returns and restricted oil to the rockers.

Run hard on the interstate for a prolonged period then take an exit and hit the brakes and watch the oil light come on and the gauge drop below 10.......... not good.
 

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Wonder how much 85 octane plays into it ?
Where can you even buy that??

Why in the world would anyone run less than 87 when 87 is specified?

I got to watch the Iowa dept of ag take their tests at a local station while I was filling up........
 

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If you look at my graphs mine is firing at -1.5 degrees at cruise during oscillation.
 

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So driving up the highway I had a sudden loss of power, a shudder and barely got off the highway as the truck died. It had a piston blown through the block. I had it towed to my dealership to have him tell me "you're the second Gladiator we got this week with a piston through the block". Mine had 11K miles, the other had 7K miles. Hope this is isolated....
Build date?
 

ShadowsPapa

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If you look at my graphs mine is firing at -1.5 degrees at cruise during oscillation.
I run 38 BTDC at about 4800 RPM on my 360.
Probably about 15 at cruising speeds - and 2,800 rpm.
 

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Where can you even buy that??

Why in the world would anyone run less than 87 when 87 is specified?

I got to watch the Iowa dept of ag take their tests at a local station while I was filling up........
https://en.m.wikipedia.org/wiki/U.S._State_Fuel_Octane_Standards

Colorado, Utah, Wyoming, South Dakota (and sort of Montana). It’s an altitude thing.

FWIW I only knew to run 87 in my old XJ as a kid in Colorado because my dad specifically told me to, otherwise 85 was the norm for everyone I knew (broke HS kids). I’m not sure if I needed it but it was in the manual so I did.
 
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Hmm this is pretty curious. Can you recall the temperature that day, the humidity and your average driving conditions before it happened?
about 60 degrees, low humidity - highway driving, accelerating up a low incline
 
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Don't you mean a rod through the block? The piston is aluminum, large, in a cylinder surrounded by coolant, and then the walls of the block around that. It would have to shoot to the side - pistons go up and down. The piston would be blocked upward by the head, downward by the crankshaft - which would shred the piston.
A rod - yeah, that I could see. They break and go sideways out the side of the block. Best example I saw was a 232 (father of the 258) with a rod that opened up a fair crack in the side of the block. The couple finished driving it back to Iowa from the middle of Nebraska on 5 cylinders that way.

As far as foaming oil - windage, they call it - when the wind caused by the crank throws aerates the oil, foams it. You lose oil pressure when that happens. You also have trouble with the lifters and other things dependent on oil pressure.
There's a lot of these that have had 6 quarts put in them, there's even a couple of TSBs out there on the topic. If 6 quarts were to cause this sort of damage, I'd expect to see a lot more of this sort of thing. And the extreme angles these run - hmmmm, I sort of doubt that was the cause.
heading in today to get some stuff out of the truck, hope to get some pictures. Shop said a piston but I agree, more likely a rod
 

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