School me on JK's

Diablo4130

Active Member
The girlfriend is wanting an Unlimited. She wants brand new because the salesman at the dealership was telling her that there were issues with the 3.8 and that the 3.6 is a much better engine. But the price for a brand new JK is unreal. I know the 3.6 has better advertised HP and TQ ratings, but those are both very high in the RPM range. I've driven both, both automatics, and barely felt a difference in noticeable power.

I know a few guys on here have had JK's. Any reason I shouldn't go with a 3.8 for her?

She's not going to go wheeling in it or anything. Just a commuter and camping vehicle and also much better in the snow than her Scion TC.

Sorry if this is the wrong forum to ask, so feel free to move this thread.

Any advice will be appreciated.

Thanks,

Kyle
 

skippy

Pretend Fabricator
Location
Tooele
She will hate any JK as daily driver, I have the 3.8 and I had to supercharge it just so driving it was tolerable. Why buy a Jeep if she isnt going to wheel it? :confused:
 

Diablo4130

Active Member
She will hate any JK as daily driver, I have the 3.8 and I had to supercharge it just so driving it was tolerable. Why buy a Jeep if she isnt going to wheel it? :confused:

Man I said the same thing. She grew up in a family with all jeeps so she has to have one. And because "she'd be cute in one." She wheels with me and I'm building a linked YJ currently. So she isn't to concerned with wheeling. She wants to have a 33" tire max and just wants a good daily driver jeep. The power thing won't be an issue I don't think as she currently drives that Scion but I feel like I may not like it. I'm just concerned about the engine issues the salesman have filled her head with.
 

skippy

Pretend Fabricator
Location
Tooele
there are far more issues with the 3.6 than the 3.8, with that being said the 3.6 feels like a rocket compared to the 3.8
 

mbryson

.......a few dollars more
Supporting Member
Come out and drive my 3.6L with gears and lift/tires. Not sure I want to sell but it'd give you an idea of whether you'll like what you get when you're done
 

sixstringsteve

Well-Known Member
Location
UT
probably not what you want to hear, but throw some $500 snow tires on the scion and it'll handle snow as well as any jeep.
 

DerekM

formerly dirk124
Location
Orem, Utah
The salesman is going to get more $$ selling a brand new Jeep... All together, my family has 5 Jk's with the 3.8. None of us have had any engine issues. The 3.8 isn't really THAT bad. I can easily maintain highway speeds with stock rubi gearing and 35's.
 
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mbryson

.......a few dollars more
Supporting Member
Are we talking 4 door or 2 door here? IMHO, a 3.8L is fine in a two door. A little lacking in a 4 door. I didn't drive a 3.6L 2 door (likely not slow?) and the 3.6L in the 4 door is pretty decent but likes to rev a LOT. I'd like a little more torque on the bottom end but it's fine. I'd still rather have a smallish V8

Edit: just noticed you're talking 4door
 
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BCGPER

Starting Another Thread
Location
Sunny Arizona
I'll make you the same offer as Marc, you can come drive my 3.8 JKU, but it's not for sale. It's a fun ride now, but I've spent a ton to get it there.

Clean 3,8's are getting hard to find. If you can find a clean used Rubicon, jump on it. The gearing will save you having to do that on the future.

I ran 35's on it with the stock 4.10's and it was tolerable. I'm running a supercharger, 5,38's and on 37's now so not quite stock. But fun!


Sent from my iPhone using Tapatalk
 

moab_cj5

Well-Known Member
Supporting Member
The 3.6, like others have said, has WAY more issues than the 3.8. The 3.8 is gutless on the highway, but it isn't a race car, its a Jeep.

If you plan on 33's max, get a 3.8l Rubicon and have fun. The manual is more tolerable than the auto, but either should be fine with just 33's. That is essentially stock on them if I recall correctly.
 

wheelewagon

Active Member
Location
West valley
I run A 3.6 and haven't had any of the issues others have. some of the early 3.6's had head issues. But they are I think right around 100 hp more then the 3.8l. If she's only going to put A max of 33's on it then the 3.8 will be fine. The 3.8 had A 4 speed in the auto and the 3.6 has a 5 speed. Funny thing though is the 5th gear is still smaller then the 3.8 4th gear. But like others have said the 3.6 likes the rpm's more. The 3.6l the switched to and aluminum block with the variable valve timed engine. But the also did away with having an exhaust manifold and made the head into the down pipe one big cast which is kinda gay I think. In 2010 I believe they went to the nicer interior which is a lot nicer imo. In 2011 they put the 5 speed in the 3.8l. Just some info for you.

If she's just driving it as A dd and wont be doing any major mods I'd get like a 2010 3.8. Or if she wants it to feel spunkier, get the 2011 3.8 with the 5 speed. the gearing will make it get up and go much better. Drive and older interior and a newer one and I think you'd rather have the newer interior as well. but what the woman wants.... It's hard to fight. also price I think will help dictate.
 

wheelewagon

Active Member
Location
West valley
Why a JK? How about a Patriot? It is at least $10K less, will get better mileage, and be more comfortable. Spend the money saved on your YJ.

I also agree with this. There's other better options for a dd I think. But I get how women want to go off of cool factor and everything.
 

TurboMinivan

Still plays with cars
Location
Lehi, UT
The salesman is going to get more $$ selling a brand new Jeep.

:rofl: Highly unlikely.

I'd like a little more torque on the bottom end but it's fine.

People always brought this up in the Car Lounge when trying to badmouth the then-new 3.6L Pentastar. We all know (or at least you should) that Chrysler chose the 3.8L V6 for the JK rather than the 3.7L V6 because of the 3.8L's greater torque output. Even still, the 3.8L didn't make quite as much grunt as the old 4.0L straight six did. To sum it up: 4.0L > 3.8L > 3.7L in torque output.

Punchline: the 3.6L makes more torque at 1800 rpm than the 4.0L did anywhere throughout its rev range... and, if you were curious, the 4.0L didn't make peak torque until 3200 rpm. The Pentastar doesn't need to rev to get moving, but it sure does like to sing if you decide to boot it.

But the also did away with having an exhaust manifold and made the head into the down pipe one big cast which is kinda gay I think.

This was a brilliant engineering move for many reasons. Here is one. The Pentastar V6 replaced six different V6 engines. Between those, there were over 32 unique exhaust manifolds in order to fit various engines into various applications. Knowing the Pentastar would become the V6 engine across the board, Chrysler integrated the exhaust manifold into the head casting. The end result? There are only 2 head configurations available, meaning four total exhaust manifold designs.
 

Bart

Registered User
Location
Arm Utah
I guess I'm wondering why all the slamming. If she wants a new Unlimited, let her get it. It's a Jeep thing, or something like that. I'm blown away by the problems Marc B has had with his 3.6, and hope that's an anomaly. My daughter had a new Rubicon Unlimited 3.8 when they first came out and loved it as a daily driver, until she had kids. There just wasn't enough room for car seats.
 

nnnnnate

Well-Known Member
Supporting Member
Location
WVC, UT
The new interior changed over in 2011. The new 3.6 liter motor came in 2012.
I love my '13 2 door sport. I DD it with rubi take offs, stock 3.21 gears (for another week), and a manual trans. I've managed to put 11k miles on it in the 6 months that I've owned it. The only thing I'd change is that I wish I would've gotten the unlimited.
 

wheelewagon

Active Member
Location
West valley
Punchline: the 3.6L makes more torque at 1800 rpm than the 4.0L did anywhere throughout its rev range... and, if you were curious, the 4.0L didn't make peak torque until 3200 rpm. The Pentastar doesn't need to rev to get moving, but it sure does like to sing if you decide to boot it.



This was a brilliant engineering move for many reasons. Here is one. The Pentastar V6 replaced six different V6 engines. Between those, there were over 32 unique exhaust manifolds in order to fit various engines into various applications. Knowing the Pentastar would become the V6 engine across the board, Chrysler integrated the exhaust manifold into the head casting. The end result? There are only 2 head configurations available, meaning four total exhaust manifold designs.


I completely agree with the upper statement. The 3.6l is a peppy little guy at all ranges and sings in the rpms.

I understand why chrysler did the head manifold. It was A smart move for them. I can't remember how much money they said they saved by doing that(an $$$t load I'm sure). But they don't pass those savings on to you and you as the consumer still end up with this big goofy shaped cast head manifold. So for A business stand point it's a smart move but for someone who wants to do exhaust mods like the ripp 3.8l headers, your kinda f-d.
 

mbryson

.......a few dollars more
Supporting Member
The new interior changed over in 2011. The new 3.6 liter motor came in 2012.
I love my '13 2 door sport. I DD it with rubi take offs, stock 3.21 gears (for another week), and a manual trans. I've managed to put 11k miles on it in the 6 months that I've owned it. The only thing I'd change is that I wish I would've gotten the unlimited.

Funny about that mileage. I've put 24k on mine in less than 16 months :eek: I really like it despite being on a first name basis with my service manager at the dealership (Frankie or CJ now---Tina is the manager). Hopefully we're done with any electronic snags? They did find something wrong with how the electrical harness was positioned in the column when they changed the clockspring. Hopefully all the stupid stuff was caused by that?

Early 2012 Pentastars had the head issue. My Jeep was "just" out of the window of production where that could be a problem. Apparently I got a kewl one? The head was really not an issue. I think they had that taken care of in a day :cool: and I was glad they did take care of me there. I still have powertrain up to 5 years/100k miles. Engine trans t-case.

This last trip the tech programmed in all my tire size/gear ratio stuff rather than me doing it with my AEV. I LOVE the shift points of the trans now. Seems like a different car. Low end torque feels a little better (it wasn't horrible, but I like big V8s and Cummins powerbands) than with the AEV programming. He mentioned there were a LOT of errors in the vehicle computer with the AEV programming. He'll check it out on my next oil change to see if the errors have went away. I really couldn't ask for more of the LHM Bountiful service dept.

Another comment on the 3.6L. It does LOVE to rev. I've not had it above 5500 RPM (at least as far as I know) but it will get there PDQ.
 
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Diablo4130

Active Member
Y'all are awesome. I just wanted an inside view on JK's before we pulled the trigger on one. I appreciate all the input and the offers to come drive one. I've really liked them since they've come out and am actually glad she wants one. Thanks again on all the input.
 
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