What to look for in a JK Unlimited?

[Moab]

I posted this on the JK forum. But only got a couple comments.

I'm selling my TJ. And looking for a JK Unlimited in the 12k range.

Any advice on what to look for, what to avoid, and what to have checked in a used JK?

 

[BlueC]

I'm selling my TJ. And looking for a JK Unlimited

Blasphemy. The only thing I can tell you is that you want the smaller engine, 3.2 in '12+ Jeeps, I think. The larger, earlier engines are known oil consumers, and I've read plenty of people claiming sub 100K miles needing a rebuild/replacement engine, but that's hearsay.

 

[RangerTJ]

After having been there/done that with a JK, here are the ones I personally would AVOID:

Anything before 2012: The 3.8 V6 in them is woefully underpowered for an Unlimited and is a complete dog. Put bigger tires on it and then the act of merging with traffic becomes an exercise in patience and the good will of other drivers.

2012-2013: These got the new 3.6 Pentastar V6 but there was a bad casting on the cylinder heads that is VERY expensive to repair if out of warranty. The issue is much improved in later years but still occasionally crops up.

2013-2014: Fiat/Chrysler/Jeep decided to redesign the oil cooler to make a single unit compatible with the 3.6 Pentastar and the smaller 3.2 Pentastar in the new Cherokee. The design is prone to cracking and can dump your oil in a matter of seconds with no warning. Sometimes you will get a puddle of oil in the intake valley as a warning that it's about to leave you stranded. I think this was finally resolved after about the 7th revision of the part.

2018: Bad solenoid packs in the automatic transmission can leave you stranded with a vehicle that won't start. Usually no warning that it's about to happen.

That leaves the 2015-2017 as the best years of JK.

ALL JKs with the Pentastar are potentially prone to the casting sand issue clogging up the cooling system. My 2017 experienced this, though I caught it before it became a big issue. My overflow tank had a layer of sludge in the bottom of it at 10k miles.

While there are plenty of JKs out there with no problems, there are also plenty that DO have problems.

Good Luck in your search.

 

[Moab]

Are any if those issues verifiably fixed by checking with the dealership? Or running codes?

I found a 2012. But with these problems. Opinions?

"Error Code P0430, Had it diagnosed and the left bank catalytic converter needs to be replaced due to inefficiency, I’ve been kicking the can down the road until I need to re-smog. Doesn’t impact drivability at all.
- Occasional burning of coolant on very hot days. When this happens I briefly get P0304 but it goes away. I’m fairly certain there’s a pinhole headgasket leak somewhere but there is no coolant in the oil and does not overheat. It’s been like this for about 5 months, had planned on fixing but new car got here sooner than expected. At some point it'll need to be addressed."

How much to have those fixed? And how can one determine that the second issue has not done damage to the engine?

Can you get a used catalytic convertor from a junkyard?

 

[RangerTJ]

The P0304 code and burning coolant problem is commonly linked to the bad cylinder head.

Chrysler extended the warranty on that to 10 years or 150,000 miles after a class action suit was brewing over it.

Unfortunately, a 2012 is out of warranty regardless. I've seen quotes of ~$4k for repair.

I'd personally pass on that one but then I'm diagnosing over the internet.

If you are genuinely interested in the Jeep, take it to a mechanic you trust and have them look at it.

 

[DavidBT]

I would just like to add that if you can find a decent 2018 JL that fits your budget, I would consider it. My wife has a 2018 JL, and other than the start/stop system, it's a great jeep. I think that the 8 speed transmission really helps the 3.6 out. And the start/stop system can be disabled.

 

[RangerTJ]

If you look at JLs, closely inspect the frame welds.

Some early JLs had a problem with very poor factory welds, in some cases to the point of being dangerous.

Apparently it can happen even on models up to 2020.

Look for very rusty welds or beads that are incomplete.

If the vehicle has ANY kind of lift or larger tires you can expect Fiat to deny any responsibility.

One Guy's Nightmare

This is a 2020 JLUR that is completely stock.

Wow.

After my 2017 Wrangler I pretty much swore off of Fiat Jeeps.

This thread is bringing back up some of the things I found on the later models.

Once again, I am sure there are good ones out there as Fiat Jeep sells tens of thousands every year.

They're just not likely to sell one to me again.

 

[Shank]

If you look at JLs, closely inspect the frame welds.

Some early JLs had a problem with very poor factory welds, in some cases to the point of being dangerous.

Apparently it can happen even on models up to 2020.

Look for very rusty welds or beads that are incomplete.

If the vehicle has ANY kind of lift or larger tires you can expect Fiat to deny any responsibility.

One Guy's Nightmare

This is a 2020 JLUR that is completely stock.

View attachment 445821

View attachment 445822

Wow.

After my 2017 Wrangler I pretty much swore off of Fiat Jeeps.

This thread is bringing back up some of the things I found on the later models.

Once again, I am sure there are good ones out there as Fiat Jeep sells tens of thousands every year.

They're just not likely to sell one to me again.

Interesting on the JL frame welds, my brother has an '18, will have to look it over.

 

[RangerTJ]

Interesting on the JL frame welds, my brother has an '18, will have to look it over.

JL Welds Issue Bulletin

I wish I could find the video that the guy posted where his entire front end shifted when he turned the steering wheel due to the track bar being barely attached.

Fiat gave him a new Jeep so I'm sure that video has been expunged from the interwebs.

Edit: I didn't find the one I was looking for but this one is similar though not quite as bad.

 

[BlueC]

Some early JLs had a problem with very poor factory welds, in some cases to the point of being dangerous.

Are these robotic made welds?

 

[RangerTJ]

Are these robotic made welds?

Yes.

 

[DavidBT]

Interesting on the JL frame welds, my brother has an '18, will have to look it over.

I will have to look my wife's over also.

 

[zebra12]

Are there many JKUs for sale for $12k?

 

[Moab]

What's the most economical way of replacing a California CARB catalytic converter? I found one on Rockauto but its $928.

I can't afford a JL. Trying to stick to 2012 and above JKU with the 3.6.