3.6 longevity solution

[roaniecowpony]

IIRC, my service manual says the oil pump solenoid is a bypass type that opens when the pump puts out excess pressure and bypasses as needed to limit pressure to ~35 psi below ~3500 rpm. It also states that upon startup, the solenoid does not bypass for a few seconds, in order to provide maximum pressure/flow to the engine, which is clear in the video I made below.

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[jellis4148]

I don't let my Jeep idle excessively, but I do let it idle till the oil is at or over 100 degrees. On trails I actually turn my A/C on if it's hot out. Not for me, but for the Jeep. That makes the fan go full blast and it helps keep the oil/coolant temps low. I actually just ordered the gen 3 940 watt fan for my Jeep. That should make a difference with temps. Anyway, isn't this like the 4th thread this month starting the same oil argument?

 

[m3reno]

Not really about oil but more about idling your Jeep.

 

[Tncdrew]

Actually, both cylinder heads are getting 60 PSI even at idle. They're plumbed differently and always get full pressure regardless of pump state. I didn't know this either until I was investigating the 3.6L hesitation issue. Part of the diagnostic was checking the cylinder head oil pressure at the VVL solenoids with a special tool (the same oil path feeds the rockers), and sure as shit they're 60 PSI even at idle while the dash says 30 PSI. This is true for the PUG engine. I don't know if the original pentastar operates this way as I've never tested it, nor does the original pentastar have VVL solenoids to even test from.

Good info.!
Thanks for posting

 

[dstevens]

What evidence is there of what the dealer said? I'm not disputing them, I'd just like to think at some point we live in an evidence based society. On my V6 it clattered like hell on a cold start and my believe was that number of cold starts was the problem more than anything else. I only have a hypothesis and no evidence of that being the cause.

Roller followers need only a tiny amount of oil compared to journal bearings. Splash lubrication works. Lifters will tell you if they don't have enough oil pressure, like I heard on a cold start.

As for oil change interval, look at the oil analysis viscosity and TBN. If they are within spec and there is no metal in the oil, then the oil is still good. Mine was good to 7500+ miles so I generally change at 6000 miles, often because I do long trips and don't want an oil change in the middle of one.

 

[Pape]

What evidence is there of what the dealer said? I'm not disputing them, I'd just like to think at some point we live in an evidence based society. On my V6 it clattered like hell on a cold start and my believe was that number of cold starts was the problem more than anything else. I only have a hypothesis and no evidence of that being the cause.

Roller followers need only a tiny amount of oil compared to journal bearings. Splash lubrication works. Lifters will tell you if they don't have enough oil pressure, like I heard on a cold start.

As for oil change interval, look at the oil analysis viscosity and TBN. If they are within spec and there is no metal in the oil, then the oil is still good. Mine was good to 7500+ miles so I generally change at 6000 miles, often because I do long trips and don't want an oil change in the middle of one.

Just wondering, is the clattering on cold start all the time or come and go ?
The reason I ask is last summer I got some major clattering on "cold start" the same I would get from sitting 1 week at 0F cold start like and cured the issue by changing the oil filter. So far my leading hypothesis is the O-ring on the filter for the by-pass seal shrinking and letting oil go to the by-pass tube.

 

[JeepinJason33]

The 5.7L makes 375hp. The 3.6L makes 300. It's barely a difference, 300 is plenty when it comes to hauling ass.

Have you driven the same vehicle with both engines? We owned a 2019 Grand Cherokee with the 3.6 and a 2020 Grand Cherokee with the 5.7. Night and day difference in performance in every aspect. Off the line it was way quicker, passing was effortless, and towing was 10X better. MPG was a bit less of course.

 

[Willys41]

Went by my dealer yesterday and spoke with the owner who owned every type of Wrangler He told me the problem with the lifters and cams comes down to two things. The oil required is too thin and letting your vehicle idle for extended long intervals. He stated that the oil shears down over time and the oil pump struggles to pump the thinned out oil and also struggles to maintain the required pressure which is needed to have everything lubricated. So his solution was to change the oil at 5,000 miles and bump it to 5w 30 and no prolonged idling. I wonder if the motor's that had issues on this site did any type of prolonged idling.

Valvoline European 5w40 and RPM Extreme JL fan controller.
Most European motor like the Maserati 3.0 gas engine (same as the 3.6) use 5w40.
The RPM Extreme JL fan controller has lowered my coolant and oil temps by 25+ degrees.

http://www.rpmextreme.com/Product/311/Jeep-JL-PWM-FAN-CONTROLLER.aspx

 

[JeepinJason33]

Valvoline European 5w40 and RPM Extreme JL fan controller.
Most European motor like the Maserati 3.0 gas engine (same as the 3.6) use 5w40.
The RPM Extreme JL fan controller has lowered my coolant and oil temps by 25+ degrees.

http://www.rpmextreme.com/Product/311/Jeep-JL-PWM-FAN-CONTROLLER.aspx

Which Maserati 3.0 are you talking about? The engine in the majority of the newer Maserati's is a twin turbo designed and built by Ferrari. It is nothing like the 3.6 at all.

 

[Willys41]

Which Maserati 3.0 are you talking about? The engine in the majority of the newer Maserati's is a twin turbo designed and built by Ferrari. It is nothing like the 3.6 at all.

PENTASTAR CARNAGE! Popped Dodge Charger 3.6 V6 Teardown. Maserati Comparison BONUS!

 

[dstevens]

Just wondering, is the clattering on cold start all the time or come and go ?

It was always after sitting at least over night, only for up to one minute, and did not always do it. Sold that vehicle and choose the 2.0T for the next engine. I did notice on the V6 that every time I did an oil change the oil filter was pretty much dry.

I'm fairly sure that FCA re-assigned the engineer who did the V6 oiling and follower design the task of designing the JL clutch.

 

[Jeep Wick]

It surprises me how many people go by dealer recommendations when they are the ones who profit from your misfortune. Early oil changes, better oil (I use 10w30), and better gas will always benefit your vehicle. These same manufacturers tell you things like transmission fluid is a 'lifetime' fill. Yeah, maybe if the lifetime is the same time the warranty runs out.

 

[Willys41]

It was always after sitting at least over night, only for up to one minute, and did not always do it. Sold that vehicle and choose the 2.0T for the next engine. I did notice on the V6 that every time I did an oil change the oil filter was pretty much dry.

I'm fairly sure that FCA re-assigned the engineer who did the V6 oiling and follower design the task of designing the JL clutch.

I had the same problem with 3.6 bone chilling rattle rattle on cold starts and I was stunned to see on my first oil change that the oil filter housing was completely void of oil and the filter did not even have oil dripping off of it.
I discovered the Baxter oil filter adapter was not convinced until my local 4x4 shop said he had installed dozens of them so I gave it a try.
I now have Baxter on both my jeep and no more bone chilling rattle rattle.
This is common scene. With the Baxter you now have two anti drain back valves.
No more draining back of the filter and oil cooler housing.

 

[drrags]

5w30 changed every 3-5,000 miles in my 2018 JKUR. Valve train failure at 59,920 miles. Personally, I think the culprit is poor heat management. 235º is not okay. I'm running an RPMExtreme fan controller in my JL now and I've got to work really hard to get it past 210º. 90% of the time it's at 199º. This is a combination of hard trails and inter-state traveling.

 

[Pape]

It was always after sitting at least over night, only for up to one minute, and did not always do it. Sold that vehicle and choose the 2.0T for the next engine. I did notice on the V6 that every time I did an oil change the oil filter was pretty much dry.

I'm fairly sure that FCA re-assigned the engineer who did the V6 oiling and follower design the task of designing the JL clutch.

The reason for the "dry filter" is the return to crank case tube, the one sealed by the o-ring I talk in my previous post that I suspect is turning bad allowing oil to go to crank case instead of the oil galley. Since your was point bad i think you may have something else on that 3.6

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