626,000 mile Pentastar teardown

Originally Posted by eyeofthetiger
I wonder how many oil coolers it went through.

Quick look shows it's $100-250 for the cooler, not sure how long it takes to swap one out. Wonder if it'd be cheap insurance to keep one on the shelf? Then again, the home DIY'er should never break one, right?
 
Originally Posted by buster
Originally Posted by OIL_UDDER
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.


Thanks for sharing.
cheers3.gif


Sounds like a 20 grade with a higher HT/HS (such as Red Line) would be a nice choice for this engine (non api approved of course). Or an API approved 30 grade, most of which have a HT/HS of 3.-3.2.


I was just thinking that a 2.9hths from redline 0w20 would be the happy medium for sure.
 
More like how many...Oil coolers. Radiator fans. Radiators, 2 plenum bolts that collect water and rust out. Lifters, rocker arms, coil packs.

All promaster common repairs. I work on them daily

Most of the guys don't maintain them which is why 600k is not a common mileage for sure

The 150k life I heard from another FCA employee in the training center before too so it's a corporate thing at least internally
 
I don´t know much about Promasters, but I´d imagine that being a commercial van, they get abused quite a bit. I´ve seen many Pentastars in Jeeps with 300k miles on them, though, and in the Jeep clubs I am in, they have an outstanding reputation for reliability and longevity. Very few report any problems with them. That´s one of several reasons I went with the 3.6 on my Jeep instead of waiting for the 2.0. (which is turning out to be a good engine, as well.) That the 3.6 was the only engine offered with a manual played a small part in it, too, but I´d have chosen it even if I wanted an auto.

I went for a joy ride tonight with doors off and top down and flogged the engine on some country roads. What a joy it is to drive this thing. Loves to rev. It pulls strongly all through the powerband, but there is a nice kick at about 4500 rpm that you can really feel, so it pulls even harder from there to red line. Not sure if that is unique to the gen 2 or to all Pentastars.
 
My 76 Olds v8 had nylon timing gears from the factory which were prone to failure, so I swapped them out with new steel ones, new chain along with the water pump, etc when I got the engine from the junkyard. It was a pretty easy, inexpensive job compared to timing sets on most modern cars, but the potential for long life is probably better on the newer stuff (short of certain engines like the 5.4 3v or other engines that have common timing chain issues.

Also talking about engine hours, my 200k Silverado has 8600 engine hours, so I guess that is equivalent to about 344k miles?
 
Originally Posted by IndyFan
I don´t know much about Promasters, but I´d imagine that being a commercial van, they get abused quite a bit. I´ve seen many Pentastars in Jeeps with 300k miles on them, though, and in the Jeep clubs I am in, they have an outstanding reputation for reliability and longevity. Very few report any problems with them. That´s one of several reasons I went with the 3.6 on my Jeep instead of waiting for the 2.0. (which is turning out to be a good engine, as well.) That the 3.6 was the only engine offered with a manual played a small part in it, too, but I´d have chosen it even if I wanted an auto.

I went for a joy ride tonight with doors off and top down and flogged the engine on some country roads. What a joy it is to drive this thing. Loves to rev. It pulls strongly all through the powerband, but there is a nice kick at about 4500 rpm that you can really feel, so it pulls even harder from there to red line. Not sure if that is unique to the gen 2 or to all Pentastars.


PUG got variable valve lift as well as more variable valve timing (20° more, for 70° vs the previous 50).
 
Originally Posted by Skippy722
Originally Posted by IndyFan
I don´t know much about Promasters, but I´d imagine that being a commercial van, they get abused quite a bit. I´ve seen many Pentastars in Jeeps with 300k miles on them, though, and in the Jeep clubs I am in, they have an outstanding reputation for reliability and longevity. Very few report any problems with them. That´s one of several reasons I went with the 3.6 on my Jeep instead of waiting for the 2.0. (which is turning out to be a good engine, as well.) That the 3.6 was the only engine offered with a manual played a small part in it, too, but I´d have chosen it even if I wanted an auto.

I went for a joy ride tonight with doors off and top down and flogged the engine on some country roads. What a joy it is to drive this thing. Loves to rev. It pulls strongly all through the powerband, but there is a nice kick at about 4500 rpm that you can really feel, so it pulls even harder from there to red line. Not sure if that is unique to the gen 2 or to all Pentastars.


PUG got variable valve lift as well as more variable valve timing (20° more, for 70° vs the previous 50).


Maybe thatś what Iḿ feeling at 4500? It is a kick in the pants, for sure.
 
Originally Posted by buster
Quote
I like this thinking. Most engines do like to be wound up now and then. I am fortunate to live on top of a hill. After a trip to the store where the SkyActiv motor is cruising at less than 2000rpm for the most part I make it a habit of going up this half mile stretch of hill in sport mode.


It certainly does seem that way. Engines like to be ran and often hard. While not scientific, you do see a lot of anecdotal evidence that suggests engines like to be driven on the more aggressive side at times. You also see that a lot of high mileage engines are driven a lot. Babying an engine is not ideal.



Exactly right buster ^^^^^^

I drive my 312,600 mile VQ motor up to 5,500 rpm almost daily.... It still runs very well. And even with the original CVT still does it very well.
 
I saw a video of the valvetrain if anyone is interested since the topic video teardown doesnt show it...

This mechanic is fixing a lifter 'tick'
 
Originally Posted by supton
Originally Posted by eyeofthetiger
I wonder how many oil coolers it went through.

Quick look shows it's $100-250 for the cooler, not sure how long it takes to swap one out. Wonder if it'd be cheap insurance to keep one on the shelf? Then again, the home DIY'er should never break one, right?


I can't remember the book time, but I do it in about 2 hours. The plastic gets brittle with all the heat. I don't think there is a way to avoid it.
I wish I could design an all-aluminum aftermarket replacement. I don't have the CAD skills.
 
I don't have direct experience with it, but I've heard the $100 aftermarket pentastar oil cooler, filter housings are junk and the sensors on them are garbage.

In regards to this 630k mile pentastar, I wonder if the catalytic converters were still good enough to keep catalyst inefficiency codes away?

It had to have gone through a couple of 62TE transaxles as well.
 
Originally Posted by eyeofthetiger
I can't remember the book time, but I do it in about 2 hours. The plastic gets brittle with all the heat. I don't think there is a way to avoid it.
I wish I could design an all-aluminum aftermarket replacement. I don't have the CAD skills.

Yep; FCA should have taken a nod from MB who makes their cooler/filter housing completely from aluminum with the cap the only thing made of plastic. From what I have read, the FCA issue may not be completely avoidable for the reason that you state, but it can be prolonged by not overtightening the filter cap. The Gen 1 cooler housings are much more expensive than the Gen 2 (more than double).
 
Originally Posted by DuckRyder
That thing had to be making some noise. All it seems to need are chains, tensioners, guides...
The Gen 2 engines had a re-design that should have reduced the possibility of those issues (time will tell).
 
Originally Posted by DuckRyder


All it seems to need are chains, tensioners, guides...


For sure on that.

Even the oil pump looked new yet.

I'm assuming his $800 low mileage used engine was less time, effort and cost once you factor any specialized tools you'd need to rebuild the top end of that 630k mile engine.

How cool would that be though to see how long that bottom end would go?
 
I find it hard to believe that you could find a low mileage used Pentastar for $800 bucks, unless he´s got some kind of deal with someone. Those engines are VERY expensive, new.
 
Originally Posted by IndyFan
I find it hard to believe that you could find a low mileage used Pentastar for $800 bucks, unless he´s got some kind of deal with someone. Those engines are VERY expensive, new.


Thought that was odd myself unless I misunderstood what the dude said in his video.
 
I like the comments about how 625k miles is wonderful. When Toyota tore down the first million mile 4.7L in the 2007 Tundra, they said it had better performance than when new and looked like it barely had any use on it.
 
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