Pentastar Startup Rattle

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You are so cute!

The 4.0 power output doesn't measure up to the Pentastar on either end. Fact. It was great in its day. But it isn't the torque monster everyone wants to remember it as. I drove one last weekend, back to back with my Jeep. It is a dog compared to the Pentastar, even with the Pentastar pushing an extra 1200 or more lbs around, plus gear. Lots more gear.
I didn’t say the 4.0 was powerful lol.

But I do have to say, my grandma has a 14’ Grand Caravan that is way faster than the Grand Cherokee.
 
Both of my 3.6L Pentastars have done the exact same thing since new.
Yep … my Rubicon only has 1100 miles and sounds like a diesel at startup … but going through the gears it has a great sound … it’s gone through a balanced break in … even waited until it had 1k on the clock before I put the pedal down at low speed …
 
2016 Caravan ticks on startup after even an hour sitting. In cooler weather it'll moan like a hydraulic pump on startup - power steering pump I think. Bought it with 57k miles, now at 90k miles. It's the loudest vehicle I've ever been in that wasn't deliberately made louder. Engine, exhaust and even transmission whine during moderate to heavy accel (no change with trans service with Mopar ATF). It sounds like a tank. But seems to run fine.
 
Mine groans when cold but that is normal. My Mom's Impala does same noise in mornings since she bought it at 35000 miles and now has 145000. The only time it has made a diesel noise was when I put Havoline Pro DS. I am running Pennzoil Platinum 5w30 right now but will go back to Valvoline 5w20 as fuel mileage has been lower. I did 6 month oil changes up to 15k as filter was nasty when I got it changed at 4500 miles. I am now doing once a year or OLM with synthetic and as I stated no noises except first start up which is normal. Can't even hear it run if standing next to it. It does have a whine at 1500 rpm that I hear slightly less with Synthetic which is probably gear noise from cams but I refuse to go to dealer as all they do is change parts. Mileage this tank has gone down as I checked today which shows 18.2 down from 20 mpg but I had car idling for about an hour with Wife in it while I shopped (Bad day for her). She is a stroke victim in a wheel chair.
 
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Due to the cartridge filter that is mounted on the top of the engine, along with the fact that this arrangement does not have an anti-drainback valve in the filter like a spin-on filter has, the oil drains out of the filter and back to the pan within 30 minutes of engine shutdown. It takes a few seconds after startup to fill the filter, and then get oil to the cams, chain tensioners and cam phasers. It's pushing air in front of the oil as the oil fills these passages. There is a cartridge to spin-on adapter out there for these engines.
 
$300 on the mfg's website, and it looks like the filter would sit up pretty high. When I first read about it here I thought it might be good, especially for vehicles that sit for long periods of time. For that kind of money I don't think it's worth it, and it might put stress on the lower part of the assembly, which IIRC can be problematic to begin with. I'd love to hear back from people who have one and see a picture of it in a Wrangler.
 
The Pentastar engines are in fact a good overall design and came out of Daimler-Chrysler. The design just fails miserably on the oil system. The base can crack when over tightening the filter cap upon installation, not removal. It is clockwise rotational force on the cap that is the cause, just screw it in until fully seated, it won’t back out.
The oil does completely drain out and back after turning off the engine and is not retained between the dual displacement pump and filter like top mounted Mercedes and BMW engines. So there is a significant delay in oil pressure, not good. The subsequent engine wear is proportional to the the the number of start cycles, not the miles on the engine.
Oil cooling is also a failure, the oil cooler is bypassed by about 50%, so hot oil is combined with the cooled oil where it enters the engine. Making maters worse, the temperature sensor is only exposed to the oil coming out of the cooler, so you never get the true oil temperature reading.
 
Yep. We talk about that a lot on pentastar threads. The oil filter housing is really the only common failure prone part.

In terms of the oil pressure scenario you describe, maybe there is a lag, but I recall the oil PSIG ramping instantly up on my 2017 Ram 1500 w/ pentastar.
 
Yep. We talk about that a lot on pentastar threads. The oil filter housing is really the only common failure prone part.

In terms of the oil pressure scenario you describe, maybe there is a lag, but I recall the oil PSIG ramping instantly up on my 2017 Ram 1500 w/ pentastar.
There is is a synthetic output from the ECU for a couple of seconds that confirms oil pressure to indicator light/gauge that there is oil pressure before reading the actual oil pressure from the oil pressure sensor. I know this due to the fact that I have actually removed the factory sensor and replaced with mechanical gauge, leaving the factory sensor removed but still attached the the electrical harnesses. Upon startup, the oil pressure light would go out for a couple of seconds and then come back on. This coincided with the mechanical gauge showing a comparatively slow climb to pressure since there was air compression until the oil feed was fully hydraulic.
 
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Dexter1, while most of what you say sounds fine, I would disagree with the fact that people over torquing a oil filter housing is in any way the manufacturers fault or design issue. Euro cars are fitted with these on every make I can think of and we do not have huge issues with cracked housings. But we don’t over tighten them. As you said wind in the cap with filter and lubricated seal until it stops. No need for any force.

Do it right, don’t blame the manufacturer for assuming people will do the job correctly.

Just my opinion.
 
Dexter1, while most of what you say sounds fine, I would disagree with the fact that people over torquing a oil filter housing is in any way the manufacturers fault or design issue. Euro cars are fitted with these on every make I can think of and we do not have huge issues with cracked housings. But we don’t over tighten them. As you said wind in the cap with filter and lubricated seal until it stops. No need for any force.

Do it right, don’t blame the manufacturer for assuming people will do the job correctly.

Just my opinion.

Yep, 18 ft lbs of torque and that's it. I use a torque wrench on mine. No issues so far.
 
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If you own a pentastar and do your own oil changes, you'll see the whole oil filter housing flex and move every time you remove and replace the cap, regardless of following specs. Even with following specs I believe they're going to leak at sometime anyway. Look at the part online. It's made with plastic and aluminum crimped together and uses quite a few O-rings that are only going to take so much movement. From top to base, it's got to be 10-12" long, so you can really stress the base.

It's a combo of the part, it's usage and where it's packaged on the engine. Kind of a pain to get to it.
 
No problems with my 2014 with 70,000 rounds. As far as the oil filter housing is concerned I love the way the filter is right on top and I have done several oil and filter changes without any trouble. I really like the engine and its very quiet.
 
Dexter1, while most of what you say sounds fine, I would disagree with the fact that people over torquing a oil filter housing is in any way the manufacturers fault or design issue. Euro cars are fitted with these on every make I can think of and we do not have huge issues with cracked housings. But we don’t over tighten them. As you said wind in the cap with filter and lubricated seal until it stops. No need for any force.

Do it right, don’t blame the manufacturer for assuming people will do the job correctly.

Just my opinion.
Just pointing out cause and effect, base cracking could be avoided by not calling out a torque specification. FCA changed the oil filter/cooler design in 2014 for design weaknesses that existed in 2011-2013.
 
Just pointing out cause and effect, base cracking could be avoided by not calling out a torque specification. FCA changed the oil filter/cooler design in 2014 for design weaknesses that existed in 2011-2013.
I agree, and the filter housing is still problematic. Regarding oil draining from the filter housing assembly, there are a lot of those engines in service with hundreds of thousands of miles with no problems. It would be nice to have designed something to keep oil from draining out of the filter assembly, and make it out of aluminum instead of plastic but it appears they weren't too concerned about it. The PUG upgrade uses the same filter as the 2014's and up.
 
Dexter1, while most of what you say sounds fine, I would disagree with the fact that people over torquing a oil filter housing is in any way the manufacturers fault or design issue. Euro cars are fitted with these on every make I can think of and we do not have huge issues with cracked housings. But we don’t over tighten them. As you said wind in the cap with filter and lubricated seal until it stops. No need for any force.

Do it right, don’t blame the manufacturer for assuming people will do the job correctly.

Just my opinion.
I see your point but at the same time, they chose to design this in a way that required a change in very old established habit. Why? To save a few bucks I presume, and perhaps the easy access was considered worth the confusion. I'm just saying when you design something that's different and breaks (pun intended) the norm you are somewhat to blame.
 
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