The jeep 3.6 engine and the wrangler ...

ord.sgt.26NC

Gott mit uns!
Joined
Mar 23, 2005
Location
Goldsboro
since I bought this 2013 wrangler,I've been wondering what are some of the issues that pop up often with this run of vehicles. Each run has them. What would these be?
 
For JKs, the biggest, most common issue is the owners. It's trending like the JL is gonna be the same way.
 
For JKs, the biggest, most common issue is the owners. It's trending like the JL is gonna be the same way.
yea agreed...fuck a grumpy jeep!
but back on topic...fellow employee has a early 15 and it recently started going into "limp home mode" randomly. Shut it off and start it back and would run fine. Has done it 3 or so times.He took it to the local "jeep" dealership and said it was an issue with the pass. head and it needed to be replaced. Now it's still under warrantee and changed on their dime. The dealership said this was a common problem known to "jeep" on the early 3.6 engines. Huh? Never heard about this.
I'm too lazy to pull googlefool out and research it. We have some real smart folks on here.
 
The early jk 3.6, early 12 had some head issues, 13 and up are nearly flawless, I have only ever heard of one later having a head issue, he neglected oul changes though.

I have two late jk,s and beet the shit out of another 13.
You have no issues to get Jimmy, it's a great engine. Change your oil regularly , with a qaulity synthetic. Dinosaurs oil does not meet the standards.

Most who have any LIMP MODE ISSUES, IS ALMOST ALLWAYS FROM IDIOTS WHO LIFT THEM AND DO NOT CENTER THE STERRING . It makes the jeep think you are sliding, traction control fault.

The 3.6 like to turn like an lsd, do not be scared to shift at 4 grand plus, it's not a 4.0, power is in the mid and upper rpm range.

Keep a qaulity air filter in it, the mopar filter is the best, do not put some k&n air filter in it, the engine will eat dust and it will not like it, factory filter only.

You got 285hp, let er eat!!
 
2014 had an issue with the oil cooler or filter housing cracking or something....
 
Yes, because people were over tightening the oil filter housing.

Other thing people look over is transfer case and differential service, cheap to do and saves you a pile down the road. Like the ol story, my carrier bearings went out,dont know why, it's because they NEVER serviced it!
 
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Other than the head issues on the early models, they seem to be a good engine, they don't like water (deep water crossing=replace engine). Most of the failures I've seen are from doing things that are not in the manual.

The best one I've seen so far is a driver bit "lost" on a DIY project, towed in, bit was "found" embedded in #4 piston. I wish I had taken a picture, replaced with a used engine that came out of a hemi project.
 
I did some digging on the head issue and it's actually more than just the early ones doing it.Oh to sit here and read all the testamonials.....geesh! I'm trying not to get panicky about it and realise there are hundreds of thousands of this engine on the roads with no issues but when you read about head after head...
 
Just drive it Jimmy. It is like the news, you only read about the bad. I got my 15 model and haven't even give anything a second thought. If something happens it happens. Gives the opportunity for an LS swap.. Lol
 
Eh, if you want to compare, look for 4.0 head/gasket issues.. you know how many are out running around still on the factory gasket.. but yet you'll find thousands of head gasket issues.. just run it, you'll be fine. If it becomes an issue, then address it.. but don't stress about it until it is. Best things you can do is to keep on top of the cooling system and address problems before they become major. For example, Honda's are bad about getting run hot and warping heads - most of the time, it's because the owner delayed changing the radiator or repairing a minor league leak, and just topping off coolant.. and then it gives out going down the road and they cook the head. Just saying.
 
oh yea,it's all good. Not gonna throw it away if it happens. My 01 supposedly was going to have head issues but i went 245 thousand miles without it cracking and the new owner isn't letting it rest any either.
 
Glad you didnt pass that up Jimmy, you wouldn't find that deal again
yea but what a trip to go get it. No more trips to Charlotte for me!
Now what to do with the rockers....
Oh in researching and watching youtube videos on rocker arm replacement,I promptly changed my oil and filter today to mobil 1 extended life and purolater filter. The plan is to change filters every three thousand miles and total change at 15 thousand. I did something similar on my 4.0 and the engine did well but I still developed the 4.0 lifter tick.What can you do?
 
I also use Mobil 1 full synthetic and change at 5,000 miles. The jeep says oil life is still still has 25% left. Better safe I guess.
 
3.6 engines are bad about the oil coolers leaking. For whatever reason these days they let engines runs 30* hotter than the old days but then require something to cool the oil??

On the 3.6, the oil cooler is under the intake in the valley. It’s surprisingly easy to change in like 30 minutes, but it cost close to $300 for the cooler. I just spent $1000 on my wife’s 3.6 when the flywheel cracked and was knocking. Had to pull the tranny and then 2 of the ears That mate to the tranny broke off the motor causing a massive oil leak. So I had to replace what they call the upper oil pan. I would say that situation is rare though.

Leaky oil cooler will fill up the valley and run down the bell housing and look a LOT like a rear main seal leak, but if you look under the plastic intake you can verify if it’s leaking or not. Simple enough fix though and I am a fan of the 3.6, even though it’s in a minivan for us (14’) it is quite powerful and gets great highway mileage.
 
I also use Mobil 1 full synthetic and change at 5,000 miles. The jeep says oil life is still still has 25% left. Better safe I guess.
hmmmm...maybe I should back up a little on the 15,000 total change then. Is jeep calling for a change at 7500 with severe service more like 3-4000?
This wrangler won't fall under the "severe " lines. Mostly a pavement pounder she will be.
To be honest,while I enjoy driving the wrangler, I get more of a testosterone injection driving the beater,tow pig 92 2fidy and shifting 5 gears using a 2 foot long stick to row my way from stop light to stop light.The wrangler is so refined.
 
Personally I don’t trust any oil past 5k miles or 6 months, everything I own gets changed every 3k miles or every 6 months. My truck sees about 5k miles a year and the Jeep about 3-4K miles a year.
 
Plus at 5k oil changes, it is easy track. When I got mine, previous owner had done the first two changes right at 5k as well, so I just continued from there. 15, 20, and so on. I also use Mopar filters. Can find them on eBay in packs of 3 for $30.
 
Personally I don’t trust any oil past 5k miles or 6 months, everything I own gets changed every 3k miles or every 6 months. My truck sees about 5k miles a year and the Jeep about 3-4K miles a year.

Ever done oil analysis? Modern oil is easily good for more than 5k especially synthetic which is what is required for the jk.
 
Ever done oil analysis? Modern oil is easily good for more than 5k especially synthetic which is what is required for the jk.
Nope and don’t care to. If you ain’t got enough money for an oil change every 5k miles something needs to change. Wife’s car runs full synthetic and Ford recommends to change every 5k miles.
 
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