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I am trying to figure out what other engines will fit in a 2013 JK. Will an engine from a Dodge Charger, Challenger, Caravan, Durango, etc. fit. They are all 3.6L Pentastar but are they interchangeable. Is there a cross reference that will have that information. Thank you to everyone for the help.....
 

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:jawdrop:

Is this to replace a defective Pentastar or are you upgrading from a 3.8?

If you're switching a 3.6 Pentastar engine, the answer is maybe assuming you:
  • Reuse the Jeep's air intake
  • Reuse the Jeep's alternator and its bracket
  • Reuse the Jeep's exhaust and catalysts
  • Reuse the Jeep's ECM computer

The first 3 are specific to the JK, the 4th specific to your JK.

You'd probably want to reuse your Jeep's lower intake, fuel rail and injectors as well.

The one thing that would scare me is the camshafts; the lobes may be specific to the Jeep's tuning and you can't just swap them; you'd have to get JK-specific heads. Or reuse yours if they're still good.

So basically the block and lower internals might be all you can swap.

An easier swap would be another JK's V6. (my 2014 has a 2013 engine)

Again, what's the motivation behind your desire to swap engine?
 

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:jawdrop:

Is this to replace a defective Pentastar or are you upgrading from a 3.8?

If you're switching a 3.6 Pentastar engine, the answer is maybe assuming you:
  • Reuse the Jeep's air intake
  • Reuse the Jeep's alternator and its bracket
  • Reuse the Jeep's exhaust and catalysts
  • Reuse the Jeep's ECM computer

The first 3 are specific to the JK, the 4th specific to your JK.

You'd probably want to reuse your Jeep's lower intake, fuel rail and injectors as well.

The one thing that would scare me is the camshafts; the lobes may be specific to the Jeep's tuning and you can't just swap them; you'd have to get JK-specific heads. Or reuse yours if they're still good.

So basically the block and lower internals might be all you can swap.

An easier swap would be another JK's V6. (my 2014 has a 2013 engine)

Again, what's the motivation behind your desire to swap engine?
Im too tired to double check right now, but Im pretty sure I checked the part numbers for the camshafts as well. Almost positive they are the same. I believe the different HP is mostly due to the intake and the tune. Possibly the exhaust design (post head) too
 

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Welcome to the Forum.
 

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I have a 2020 Gladiator 3.6 engine I pulled for a HEMI upgrade. Looks like I am limited to who can use the complete assembly due to the variable lift valves system.
 

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I have a 2020 Gladiator 3.6 engine I pulled for a HEMI upgrade. Looks like I am limited to who can use the complete assembly due to the variable lift valves system.
Welcome to the Forum!
 

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I have a 2020 Gladiator 3.6 engine I pulled for a HEMI upgrade. Looks like I am limited to who can use the complete assembly due to the variable lift valves system.
Yes. Right now beyond JT/JL you’re looking at only late model vehicles. Since it was first introduced on 2016 Durango/Grand Cherokee.
 

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That's a pretty high compression ratio
It is always brought up that these are these motors have a compression ratio, but I don't think that people fully understand what the VVT and VVL do. The compression ratio is really only that high during low RPMs and the variable valve systems reduce the dynamic compression ratio at higher RPMs. This allows it to have good high RPM HP with little chance of detonation while retaining a stable idle and low RPM torque.
 

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It is always brought up that these are these motors have a compression ratio, but I don't think that people fully understand what the VVT and VVL do. The compression ratio is really only that high during low RPMs and the variable valve systems reduce the dynamic compression ratio at higher RPMs. This allows it to have good high RPM HP with little chance of detonation while retaining a stable idle and low RPM torque.
This is a concept of VVT I am unaware of. I had thought compression ratio was determined by combustion chamber size before and after the compression stroke of the piston, when the valves are closed. The only way to adjust that is adjust the length of stroke, or at least that was what I thought. How does this work, open them prior to full compression thus releasing the pressure sooner? Given the compression ration also determines how the fuel burns, it seems less compression is less efficient burn.

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Dont know where you are located but there is a 3.6 pentastar with 20k miles from a 2017 rubicon down here in south florida for 2.5k obo. Guy says he did a ls swap and has proof of it running before he took it out. Dont know if thats a good deal.
 

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This is a concept of VVT I am unaware of. I had thought compression ratio was determined by combustion chamber size before and after the compression stroke of the piston, when the valves are closed. The only way to adjust that is adjust the length of stroke, or at least that was what I thought. How does this work, open them prior to full compression thus releasing the pressure sooner? Given the compression ration also determines how the fuel burns, it seems less compression is less efficient burn.

Sent from my SM-G975U using Tapatalk
Yes it holds the valves open to let some of the pressure off. Look up dynamic compression ratio. It is the more accurate way of determining cylinder pressure and the valve timing has alot to do with it.

Higher compression does have a more efficient burn but at the cost of possibly introducing detonation at higher RPM. VVT offers the best of both worlds. It can run efficiently with good torque at low RPMs and run without detonation at higher RPM.

The new JLs have a higher static compression ratio, but also have a higher degree of cam phasing possible. My guess is that at higher RPM the dynamic compression ratio isn't too far off from where the JK 3.6 is, but I haven't run the numbers to confirm that.
 

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Did anyone ever confirm if they will or will not fit ? I have a line on a 3.6 from a 300c but im not sure if the heads and cams are the same
 

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Did anyone ever confirm if they will or will not fit ? I have a line on a 3.6 from a 300c but im not sure if the heads and cams are the same
Welcome to the Forum, from Cave Creek AZ.
 

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Did anyone ever confirm if they will or will not fit ? I have a line on a 3.6 from a 300c but im not sure if the heads and cams are the same
The 300s never got the PUG version yet so yes it will work. You will need to swap the the upper intake and timing cover from your jeep though.
 
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