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Does WOT really help the Pentastar?

Does WOT really help the Pentastar?


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Jeep Junkie

Jeep Junkie

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Like Joe I also wait until my temps are warm and give her a little WOT once or twice a week. But my 3.45s I’m sure are not a fan of that! This thing is a dog with those gears. And what’s strange is that putting the 35s on it didn’t change the way it drives compared to the stock 245/75/17 highway tires. It was a dog before the big tires and still a dog. But it’s my dog. And I love it!
4.88 has made my tiny Jeep a rocket ship. Problem is my Jeep is too high and unstable. Straight line is my strength 😃👍
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YGBSM392

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Jeep Wrangler JL Does WOT really help the Pentastar? 1750506616250-6g
 

jbcrane

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Gotta admit this “engineer” post makes me SMH...

...Next best thing, quality oil and change it every 3k miles with a quality filter. That’s what I’ve gathered.
"Damnit Jim, I'm a Jeep driver, not an engineer!" (Please don't miss the Star Trek reference :). That's my approach too: put in good oil frequently, once a week drive it like you stole it - and turn off ESS. Done and done.
 

bllprk

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The pentastar design engineer says yes, do it.

Nice! As an former Pentastar design engineer I am slightly bias but the engine is really high quality. Few points from the development using tens of millions of dollars in analysis and testing regarding the oil and durability..... The lighter oil was chosen mostly for fuel economy BUT engineering is the science of compromise. You help one thing but hurt another. A thicker oil will reduce timing chain and tensioner wear because the center timing chain idler doesn't go fully hydrodynamic till about 1650rpm on 5w-20. So, a thicker oil will lower that number slightly and with general loads/speeds the engine spends a lot of time around 1500-1750 rpm with the 8 speed. So thicker oil is a win there. Additionally, the earlier engines had what was called the "McDonald's Arches" in the idler bearing which was intended in making a more uniform distribution but in actuality acted as a knife edge. This design was changed around 2014 to a smooth bearing. So overall timing chain issues will likely follow the 2011-2014 engine years more than 2014+. Where you lose.... The head is very complicated with a Type II valve train. Meaning lots of things to pressurize and pump up at start up. A thicker oil didn't do so well here (on long sit times +cold start) and contributed to a overall increased engine wear especially in the head and cam bearings. Last point. This engine needs occasional WOT runs if you want it to last. Granny cycling is bad for it. So bad for it we actually created a new granny cycle test during the cylinder #3 misfire issue. The highest wear is in the valve guides, because of tight valve stem seals (for emissions, reduce oil burn). They basically dry out. When you go WOT/high rpm/load you get some fresh oil in there and this keeps the wear down. Thicker oil might not help this condition but we also change the valves/guides/seals in 2014+. Not sure the impact. Cheers! Kevin PS. Turn off stop start and do not run e85 if you are concerned about engine wear. Eats the engine alive.
Amazing info! Thank you!!! Any thoughts on the passenger side cam wear related to oil viscosity? The premium version with VVL and VVT? Again! Thank you. This forum is a rough place, but there are a ton of us on here who just want to learn.
 

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The pentastar design engineer says yes, do it.

Nice! As an former Pentastar design engineer I am slightly bias but the engine is really high quality. Few points from the development using tens of millions of dollars in analysis and testing regarding the oil and durability..... The lighter oil was chosen mostly for fuel economy BUT engineering is the science of compromise. You help one thing but hurt another. A thicker oil will reduce timing chain and tensioner wear because the center timing chain idler doesn't go fully hydrodynamic till about 1650rpm on 5w-20. So, a thicker oil will lower that number slightly and with general loads/speeds the engine spends a lot of time around 1500-1750 rpm with the 8 speed. So thicker oil is a win there. Additionally, the earlier engines had what was called the "McDonald's Arches" in the idler bearing which was intended in making a more uniform distribution but in actuality acted as a knife edge. This design was changed around 2014 to a smooth bearing. So overall timing chain issues will likely follow the 2011-2014 engine years more than 2014+. Where you lose.... The head is very complicated with a Type II valve train. Meaning lots of things to pressurize and pump up at start up. A thicker oil didn't do so well here (on long sit times +cold start) and contributed to a overall increased engine wear especially in the head and cam bearings. Last point. This engine needs occasional WOT runs if you want it to last. Granny cycling is bad for it. So bad for it we actually created a new granny cycle test during the cylinder #3 misfire issue. The highest wear is in the valve guides, because of tight valve stem seals (for emissions, reduce oil burn). They basically dry out. When you go WOT/high rpm/load you get some fresh oil in there and this keeps the wear down. Thicker oil might not help this condition but we also change the valves/guides/seals in 2014+. Not sure the impact. Cheers! Kevin PS. Turn off stop start and do not run e85 if you are concerned about engine wear. Eats the engine alive.
I just want to say I was impressed with the power out of this engine. I started driving in the 1980s. There was no way a 6 cylinder would push 35" tires (which at the time would have been huge. You needed to have a 4" lift on a square body Chevy to run 33s) with 3.45 gears. It's quite a bit more powerfull than a stock 350SBC from the day.
Unfortunately now I have a tick from the right side. My Wrangler is a 2019 so it has the super expensive intake rockers and the cam kit is on back order with no date.:mad:
 

mrtm1970

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What you have to understand is that ALL engines are at their most efficient at WOT (of course with the proper lubrication happening) … that is fuel efficiency, mechanical part efficiency. Actually the worst for everything is at idle and very low RPMs.

My recent theory on all the JL/JK/JT engine issues (more than other Jeep products) is just THIS 👆

I sadly have not taken my JLUR off 4 wheeling other than some beach sand and flat trails and I am at 125,000 miles and just seeing the engine wear issues. It seems everyone who 4 wheels their JL/JK/JT are seeing these issues as low as 37k mile because MOST of their 4 wheeling are running in the 1500-3000 rpm range and sometimes having to hammer the engine up to 5000-6000 rpm to get over some very hard obstacles. THIS is not conducive to what the optimal engine performance was really designed for and why we are seeing the majority (not saying other automotive products using the same engines are having the same issue) of these failures happening in our vehicles.
 
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Gotta admit this “engineer” post makes me SMH. He’s proud of an engine with such prominent conflicting needs. We “stupidly” spent millions in testing yet wouldn’t address the shortcomings. SMH lol

There’s some redeeming value in it though. It gives some insight for trying to address both problems with the latest lubrication advancements which have come along a fair amount since the design of the engine and even the latest PUG iteration.

It whispers to me “PAO/Ester base oil 0w-40 with the strongest anti-wear additive pack and Star polymer VII available.” Best cold flow, sacrificial layer when the oil boundary layer (Stribeck Curve) film fails, and the strongest shear stability. So spending $80-$100 an oil change for just the oil and change it every 3-5k miles if you don’t test though it will likely go MUCH further than that I’ve read. Some are ridiculous.

Next best thing, quality oil and change it every 3k miles with a quality filter. That’s what I’ve gathered.

Got some HPL PCMO Premium Plus 0w-40 on the way. At the end of the second oil charge I’m considering getting an oil sample sent and requesting sub 5 micron results too. Then I’ll compare that to the next sample results to look for a trend.
I agree with this. This “engineer” hear-say is always a bit of a fluke. Somewhere I’ve read about another “engineer” contradicting some of the statements here. Then add the factor of time to it and however long these engineers haven’t been part of the development cycle and in a nutshell, we know nothing of the internal Stellantis opinion of how to run a latest-gen Pentastar.
 

NPC 20883467

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As an former Pentastar design engineer I am slightly bias but the engine is really high quality...
That... is where he lost me. Even if I accepted his premise, If I ran a car company I'd like my "engineers" to at least be literate.
 

mrtm1970

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That... is where he lost me. Even if I accepted his premise, If I ran a car company I'd like my "engineers" to at least be literate.
Actually, I tell people all the time, I went to school for Engineering NOT English :lipssealed: :CWL:🤪
 

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The pentastar design engineer says yes, do it.

Nice! As an former Pentastar design engineer I am slightly bias but the engine is really high quality. Few points from the development using tens of millions of dollars in analysis and testing regarding the oil and durability..... The lighter oil was chosen mostly for fuel economy BUT engineering is the science of compromise. You help one thing but hurt another. A thicker oil will reduce timing chain and tensioner wear because the center timing chain idler doesn't go fully hydrodynamic till about 1650rpm on 5w-20. So, a thicker oil will lower that number slightly and with general loads/speeds the engine spends a lot of time around 1500-1750 rpm with the 8 speed. So thicker oil is a win there. Additionally, the earlier engines had what was called the "McDonald's Arches" in the idler bearing which was intended in making a more uniform distribution but in actuality acted as a knife edge. This design was changed around 2014 to a smooth bearing. So overall timing chain issues will likely follow the 2011-2014 engine years more than 2014+. Where you lose.... The head is very complicated with a Type II valve train. Meaning lots of things to pressurize and pump up at start up. A thicker oil didn't do so well here (on long sit times +cold start) and contributed to a overall increased engine wear especially in the head and cam bearings. Last point. This engine needs occasional WOT runs if you want it to last. Granny cycling is bad for it. So bad for it we actually created a new granny cycle test during the cylinder #3 misfire issue. The highest wear is in the valve guides, because of tight valve stem seals (for emissions, reduce oil burn). They basically dry out. When you go WOT/high rpm/load you get some fresh oil in there and this keeps the wear down. Thicker oil might not help this condition but we also change the valves/guides/seals in 2014+. Not sure the impact. Cheers! Kevin PS. Turn off stop start and do not run e85 if you are concerned about engine wear. Eats the engine alive.
Did Kevin design the cams?
 

The Last Cowboy

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So what is the proper way to do WOT? Here is how I did it.
Coming home on the highway all my temperatures were great, oil temp was 214, I saw steep stretch infront of me, there was no traffic behind me, I slowed down to 40 mph, then gradually started accelerating and then floored it and counted till 10 and then released it. Is that the proper way?
I wait until the engine is fully warmed up. Then I will accelerate from a low speed, about 5 MPH, to as fast as I can can get away with. Any time I'm on a steep grade I try to take advantage of the load it adds to the vehicle. I can make the engine work harder in a shorter span of distance. I've been known to turn around and take the hill again. Listening to the engine at WOT on grade can tell you a whole lot about any issues that arise. The main reason I do this are to burn off any condensation in the oil, and to clean as much carbon out of the engine as possible. There is also the benefit of oil reaching places t high RPM, it normally wouldn't if it wasn't ran hard.

Where I am, ambient temps are usually very high for 4-5 months of the year. I've used Pennzoil Platinum 5w30 since new. I recently switched to M1 EP 5w30 for the PAO blend and have a noticeable reduction of valve train noise. I considered M1 Euro 5w40, but I'll try a year of what I have. And I say a year, because it will take that long to put 5k miles on it.
 

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Hi from TN! This forum has taught me so much, but I sometimes have trouble with acronyms and what they mean. Does "WOT" mean Wide Open Throttle?

I wish there was a glossary sometimes on here somewhere 😂
 

Zandcwhite

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Hi from TN! This forum has taught me so much, but I sometimes have trouble with acronyms and what they mean. Does "WOT" mean Wide Open Throttle?

I wish there was a glossary sometimes on here somewhere 😂
You nailed it. Wide open throttle.
 
 







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