3.6 engine and 87 octane a no-no

[Creeker]

Interesting SAE paper about pre-ignition (pre-detonation) at low RPM

https://www.fev.com/fileadmin/user_...arged_direct-injected_gasoline_engines_01.pdf

A couple of clips from above.

In contrast to conventional engine knocking in gasoline engines, which is typically controlled by knock control algorithms in the ECU, pre-ignition is considered uncontrollable. According to Heywood [1] knocking is the self-ignition process in the end-gas regime prior to arrival of regular flame front and is dependent on temperature and pressure time history. It can be controlled by spark timing adjustments and all modern gasoline engine control units have specific knock control algorithms in order to react to knocking combustion. Pre-ignition on the other hand is characterized by a start of combustion prior spark ignition without the inducement of local component overheating. These sharp erratic cracks caused by the significantly increased fuel conversion rate can lead to significantly higher cylinder peak pressures, much higher than typically seen in knocking events. The peak pressures and maximum rise rates as measured during pre-ignition can lead to instant severe engine damages. Therefore it is important to understand the Page 2 of 20 mechanisms which lead to pre-ignition in order to make engines less sensitive to pre-ignition. Only then it will be possible to push the envelope to even higher load levels within gasoline engines.

From the results obtained by the performed DOE test runs it can be furthermore derived that fuel quality (B) seems to have by far the biggest impact on pre-ignition threshold variance (8bar), followed by enrichment (G) and intake temperature (D), whereas spark plug design (E), and injection timing (H) strongly influence pre-ignition threshold robustness.

Granted that the paper above focuses on turbo engines and direct injection issues. However, pre-ignition can be heard on the 3.6 engine when running 87 octane and wheeling/crawling at low RPM. For the ECU to control knocking (pre-detonation, pre-ignition, pinging, etc.) that means that the ECU is "hearing" the pinging and changing the engine controls to avoid the pinging. Therefore, pinging is still occurring in the engine.

Based on the information in this SAE paper and other SAE papers, IMHO, this pinging sound in a Jeep engine is not good. How bad is the pinging in a 3.6 motor and what are the long term effects, who knows. My rig is going to run on 93 octane. It's your rig, run what you want.

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[DanW]

The only product from lucas I use is the fuel additive .. and have done for decades on a few vehicles. Actually, I don't use anything else... any additives anywhere else on any car ..they get straight everything. I don't claim to know every thing but I had only good results with it ....never a negative. ...If u let the tank full sit a long time this helps to keep the fuel from going stale so quickly. One thing I don't get is how the heavy oil should affect the cat so directly unless he's pushing it through the exhaust . If he is and no problems I should be ok with mine.

The heavy oil in Lucas Heavy Duty Oil Stabilizer could possibly affect the cat because there may be no additives to control how it burns. (Highly likely it has none.) One of the requirements of later API ratings is that the oil/oil mist coming through the PCV can burn off without leaving anything behind in the cat converters that degrade them over time. It relies on the additives in the oil you are mixing it with and that changes their makeup or dillutes them to where I don't believe they are as effective. My humble opinion is that it is a risky proposition to run it. The good news is that modern reputable oils are very very good and may handle it, but in the PUG, 1 quart is 20%. If it is a 50 weight, mixing 20% with a typical 20 weight takes the kinnematic viscosity at 212 degrees F to a 40 weight. The 3.6 is not and never was designed to run a 40 weight oil. If it is a 40 weight, it moves it to a thick 30 weight. The 3.6 originally was designed for 5w30, but the PUG was never intended for a 30 weight, so I'm taking no chances with the resdesigned valve train.

Now here's the fun part. I just looked up Lucas' own data sheet on this stuff. Take a look at the Kinematic viscosity at 212 degrees (100 degrees C). HOLY COW BATMAN!!! It is 110. That is insane! So let's go back to the calculator and see what 20% of that does to the nice 0w20 in your engine....21.9 to 26.1 is a 60 weight. This stuff must be around 260 weight! NO FRIGGIN WAY that gets in ANY of my engines.

The more I read up on this product, the scarier it is. I'd only use it in an engine that is just flat worn out and on its last leg and where I'm trying to get a thousand more miles of life out of it.

Just reading Lucas' description of this product in their technical data sheet should give you great pause in putting it in one of these engines, or any non-industrial application. It looks to me to be a bandaid for a worn out engine. Period. I don't believe they offer any kind of warranty, either, unlike oils intended for your engine.
That should give pause, too. (Pennzoil, Mobil 1, Valvoline, and others warrant your engine for oil related breakdown when using their products.)

Back to the topic....I think this stuff would stop pinging/knocking, eventually. In fact, at that point, your engine won't make any noise at all.

Of course, this is all just my opinion. If you want to put it in your engine, knock yourself out. (LOL, see what I did there?) My buddy puts a quart in every oil change on his Pentastar. I think he's going to pay for it later, big time.

 

[DanW]

This is off topic, but there are some resources on oil viscosity and Lucas Heavy Duty Stabilizer that you might want to see. And by the way, I would bet a significant amount of money that FCA would void the warranty on any engine issue if they knew it was being run with Lucas Heavy Duty Oil Stabilizer in it. And I wouldn't, either, if I were them.

Lucas HD Oil Stabilizer Marketing Page

Lucas HD Oil Stabilizer Technical Data Sheet

Oil Viscosity Range Chart

Oil Mixing Viscosity Calculator

Enjoy!

 

[Petey]

The heavy oil in Lucas Heavy Duty Oil Stabilizer could possibly affect the cat because there may be no additives to control how it burns. (Highly likely it has none.) One of the requirements of later API ratings is that the oil/oil mist coming through the PCV can burn off without leaving anything behind in the cat converters that degrade them over time. It relies on the additives in the oil you are mixing it with and that changes their makeup or dillutes them to where I don't believe they are as effective. My humble opinion is that it is a risky proposition to run it. The good news is that modern reputable oils are very very good and may handle it, but in the PUG, 1 quart is 20%. If it is a 50 weight, mixing 20% with a typical 20 weight takes the kinnematic viscosity at 212 degrees F to a 40 weight. The 3.6 is not and never was designed to run a 40 weight oil. If it is a 40 weight, it moves it to a thick 30 weight. The 3.6 originally was designed for 5w30, but the PUG was never intended for a 30 weight, so I'm taking no chances with the resdesigned valve train.

Now here's the fun part. I just looked up Lucas' own data sheet on this stuff. Take a look at the Kinematic viscosity at 212 degrees (100 degrees C). HOLY COW BATMAN!!! It is 110. That is insane! So let's go back to the calculator and see what 20% of that does to the nice 0w20 in your engine....21.9 to 26.1 is a 60 weight. This stuff must be around 260 weight! NO FRIGGIN WAY that gets in ANY of my engines.

The more I read up on this product, the scarier it is. I'd only use it in an engine that is just flat worn out and on its last leg and where I'm trying to get a thousand more miles of life out of it.

Just reading Lucas' description of this product in their technical data sheet should give you great pause in putting it in one of these engines, or any non-industrial application. It looks to me to be a bandaid for a worn out engine. Period. I don't believe they offer any kind of warranty, either, unlike oils intended for your engine.
That should give pause, too. (Pennzoil, Mobil 1, Valvoline, and others warrant your engine for oil related breakdown when using their products.)

Back to the topic....I think this stuff would stop pinging/knocking, eventually. In fact, at that point, your engine won't make any noise at all.

Of course, this is all just my opinion. If you want to put it in your engine, knock yourself out. (LOL, see what I did there?) My buddy puts a quart in every oil change on his Pentastar. I think he's going to pay for it later, big time.

The heavy oil in Lucas Heavy Duty Oil Stabilizer could possibly affect the cat because there may be no additives to control how it burns. (Highly likely it has none.) One of the requirements of later API ratings is that the oil/oil mist coming through the PCV can burn off without leaving anything behind in the cat converters that degrade them over time. It relies on the additives in the oil you are mixing it with and that changes their makeup or dillutes them to where I don't believe they are as effective. My humble opinion is that it is a risky proposition to run it. The good news is that modern reputable oils are very very good and may handle it, but in the PUG, 1 quart is 20%. If it is a 50 weight, mixing 20% with a typical 20 weight takes the kinnematic viscosity at 212 degrees F to a 40 weight. The 3.6 is not and never was designed to run a 40 weight oil. If it is a 40 weight, it moves it to a thick 30 weight. The 3.6 originally was designed for 5w30, but the PUG was never intended for a 30 weight, so I'm taking no chances with the resdesigned valve train.

Now here's the fun part. I just looked up Lucas' own data sheet on this stuff. Take a look at the Kinematic viscosity at 212 degrees (100 degrees C). HOLY COW BATMAN!!! It is 110. That is insane! So let's go back to the calculator and see what 20% of that does to the nice 0w20 in your engine....21.9 to 26.1 is a 60 weight. This stuff must be around 260 weight! NO FRIGGIN WAY that gets in ANY of my engines.

The more I read up on this product, the scarier it is. I'd only use it in an engine that is just flat worn out and on its last leg and where I'm trying to get a thousand more miles of life out of it.

Just reading Lucas' description of this product in their technical data sheet should give you great pause in putting it in one of these engines, or any non-industrial application. It looks to me to be a bandaid for a worn out engine. Period. I don't believe they offer any kind of warranty, either, unlike oils intended for your engine.
That should give pause, too. (Pennzoil, Mobil 1, Valvoline, and others warrant your engine for oil related breakdown when using their products.)

Back to the topic....I think this stuff would stop pinging/knocking, eventually. In fact, at that point, your engine won't make any noise at all.

Of course, this is all just my opinion. If you want to put it in your engine, knock yourself out. (LOL, see what I did there?) My buddy puts a quart in every oil change on his Pentastar. I think he's going to pay for it later, big time.

Ur friend is a jeep renegade if he's putting such an oil in the crankcase.

 

[DanW]

Ur friend is a jeep renegade if he's putting such an oil in the crankcase.

He swears by it but can't explain the benefit in his 3.6 other than what it says on the bottle. It is another form of faith-based maintenance!

I do think he discovered it with an old late 90's Tahoe he had with a 5.7. He never changed the oil and just kept adding it. It was Mobil 1, but even that needs to be changed. Amazingly, it ran to over 200k miles. But then it started burning the hell out of oil and laying down smoke screens better than a Bradley Fighting Vehicle. I think that's when he started using it and extended the life of that engine a little bit before it finally siezed up.

That 5.7 knocked and pinged so badly it sounded like a diesel! (Had to get somewhat back on topic! Lol!)

 

[Petey]

He swears by it but can't explain the benefit in his 3.6 other than what it says on the bottle. It is another form of faith-based maintenance!

I do think he discovered it with an old late 90's Tahoe he had with a 5.7. He never changed the oil and just kept adding it. It was Mobil 1, but even that needs to be changed. Amazingly, it ran to over 200k miles. But then it started burning the hell out of oil and laying down smoke screens better than a Bradley Fighting Vehicle. I think that's when he started using it and extended the life of that engine a little bit before it finally siezed up.

That 5.7 knocked and pinged so badly it sounded like a diesel! (Had to get somewhat back on topic! Lol!)

I heard of a few that ran their car that way. (one of the old girlfriends ran her civic this way also) The oil they put in is used in the combustion process by way of cylinder walls, in some cases by valve seals and a combo of both . The actual oil change process was just cracking open a new bottle of oil and pouring it in. (yeah, I know, should we be ever this lucky) So one day she calls me up and tells me her car won't start and run. I get there and I found out that she burned up so much oil from her previous pour (ahem , lets call it oil change in her case) that the lifters never pumped up. I poured some oil in and was along my marry way. Needless to say her car ran for a year or so after that, maybe more. She forgot to do her due diligence one day i figure, and it left her stranded. The point here is that she didn't even use any additives . just plain oil.

 

[Hound Dog]

The heavy oil in Lucas Heavy Duty Oil Stabilizer could possibly affect the cat because there may be no additives to control how it burns. (Highly likely it has none.) One of the requirements of later API ratings is that the oil/oil mist coming through the PCV can burn off without leaving anything behind in the cat converters that degrade them over time.

I think that if you have so much oil mist that is 1/5th stabilizer coming through your system and not getting burned during the gasoline vapor explosion of a couple thousand degrees in the cylinder, then not getting burned by the cat that operates around 800 degrees constantly and it is clogging up your cat...... You have bigger problems than pinging...

Heck, my YJ would suck some oil direct into the system and just smoke a bit. It still burned anything that went through it.

 

[DanW]

I think that if you have so much oil mist that is 1/5th stabilizer coming through your system and not getting burned during the gasoline vapor explosion of a couple thousand degrees in the cylinder, then not getting burned by the cat that operates around 800 degrees constantly and it is clogging up your cat...... You have bigger problems than pinging...

Heck, my YJ would suck some oil direct into the system and just smoke a bit. It still burned anything that went through it.

Some vehicles can do that like your YJ. I had a YJ, too, and it was pretty much bullet proof.

The point was simply that one of many issues the Lucas HD stabilizer might cause is early retirement of the cats. It could also cause issues with a myriad of sensors. I also think it is too thick to get to many of the complex moving parts quickly enough in a modern complex engine. Then there's depsits. Again, it is relying on the additive pack in the other 80% of what's in the crank case. Those oils are not designed to boost or carry that 20% like that. But some are good enough that maybe they still can. I just would not even consider risking it. No way.

I really think that stuff is best left to old engines that are on their last leg that need to be nursed a little further. Of course the EPA won't like that much, but that's probably the only good use I can think of for that thick stuff. Maybe gears, but it isn't even API certified for that and probably has none of the additives you would need. But it still might do ok there.

What really concerns me is that Lucas even recommends it to be mixed in with ATF. So in my mind, the only certification that stuff has is from me. It is 100% WTF certified. In fact, it exceeds my standards for WTF.

 

[N75]

My 2019 Sahara pings all the time. It's a 6MT so it's easy to wind up at low RPMs under some load (starting from a stop for example) without the buffer of a torque convertor, and on 87 at sea level I can't NOT make it detonate. It's not constant but I could go out there right now and make it do it easily.

I've read that the 3.6 is known to FCA to detonate at low RPM at high load and it's a known thing they've acknowledged as "normal". Personally haven't bothered trying higher octane gas. Jeep runs great, the detonation is known from even the JK Pentastar so why stress about it? If it bugs you, run higher octane.

 

[Petey]

My 2019 Sahara pings all the time. It's a 6MT so it's easy to wind up at low RPMs under some load (starting from a stop for example) without the buffer of a torque convertor, and on 87 at sea level I can't NOT make it detonate. It's not constant but I could go out there right now and make it do it easily.

I've read that the 3.6 is known to FCA to detonate at low RPM at high load and it's a known thing they've acknowledged as "normal". Personally haven't bothered trying higher octane gas. Jeep runs great, the detonation is known from even the JK Pentastar so why stress about it? If it bugs you, run higher octane.

Thnx, good to know as most of the users insist that these engines don't ping and it's just a fairy tale. In my case the pinging does cause discomfort.. the slight torque spikes makes it difficult drinking my tai tea without spilling a few drops on my lap. Yes I'm being a bit finicky here but it's a 2020 model not a 1920. I do expect more. It is RWD with a solid axle.. putting a trailer on it is going to be problem for the darn thing. The JL has a better power to weight ratio than my previous suv yet it pings even when not fully loaded. This is sad.

 

[DanW]

Thnx, good to know as most of the users insist that these engines don't ping and it's just a fairy tale. In my case the pinging does cause discomfort.. the slight torque spikes makes it difficult drinking my tai tea without spilling a few drops on my lap. Yes I'm being a bit finicky here but it's a 2020 model not a 1920. I do expect more. It is RWD with a solid axle.. putting a trailer on it is going to be problem for the darn thing. The JL has a better power to weight ratio than my previous suv yet it pings even when not fully loaded. This is sad.

Come drive mine. No ping. I've not driven a single Pentastar with a ping.

I've heard that sometimes a Typhoon class SSBN will have one ping only, though.

 

[JeepU4IA]

Thnx, good to know as most of the users insist that these engines don't ping and it's just a fairy tale. In my case the pinging does cause discomfort.. the slight torque spikes makes it difficult drinking my tai tea without spilling a few drops on my lap. Yes I'm being a bit finicky here but it's a 2020 model not a 1920. I do expect more. It is RWD with a solid axle.. putting a trailer on it is going to be problem for the darn thing. The JL has a better power to weight ratio than my previous suv yet it pings even when not fully loaded. This is sad.

You can add me to the list of people whose Pentastars ping with 87 octane fuel. It happens only in warm weather, low RPM, and under load but it does happen. I get gas almost exclusively from Costco.

I switched to 91 octane and the pinging stopped entirely and the engine seems to run smoother. Maybe it's all in my mind but that is enough for me. I will never use 87 octane fuel again.

 

[Petey]

Come drive mine. No ping. I've not driven a single Pentastar with a ping.

I've heard that sometimes a Typhoon class SSBN will have one ping only, though.

Come drive mine. No ping. I've not driven a single Pentastar with a ping.

I've heard that sometimes a Typhoon class SSBN will have one ping only, though.

considering the cost of the tuner I might accept the 'ping' in its current state , but it certainly seems it would work better then anything else.

 

[Petey]

You can add me to the list of people whose Pentastars ping with 87 octane fuel. It happens only in warm weather, low RPM, and under load but it does happen. I get gas almost exclusively from Costco.

I switched to 91 octane and the pinging stopped entirely and the engine seems to run smoother. Maybe it's all in my mind but that is enough for me. I will never use 87 octane fuel again.

.. we all can't be imagining things ... even the little green man that just walked by me a second ago told me so. ok ....maybe that's just me..Ur pretty much on the same boat. But my next fill up will be the high grade stuff also. It's predictable what will happen . I'm positive that an adjustment in the fuel and spark curve maps would fix this and 87 would be possible..will a tuner do it? And how well... nobody seems to know.

 

[Zotch]

Ping.

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