4.0 liter swap?
02-01-2016, 05:49 PM
#11
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I dislike the electronic control everything on the 3.6. As far as gas mileage, both of my REAL Cherokees get far better gas mileage than my 2012 JK. I get about 14-15 MPG daily driving on the JK. The 94 & 98 XJ's get 17-18 daily driving, and the 98 is an automatic. I am currently building a 4.7 stoker for the 94 2 dr XJ. My friend has one in his XJ, and she pulls from the bottom. Even the stock 4.0s pull from the bottom. The JK can't get out of it's own way below 1500 RPMs. Then it stumbles randomly while driving, either because of the fly by wire throttle or the drivers side cylinder head. Plus it has already thrown an oil pump code once, that hasn't come back yet. I just wanted something reliable, and this JK isn't it. I don't trust it not to fail. Plus my lifted XJ does wheel better, with about the same lift (the JK has more). I am also considering finding another Wrangler pre-99 to build. I do really like the YJ platform. I will never buy a new Fiat product. The Cherokia's, and Renegay's are fine for folks that don't want to really go off road. That is why I do like the JK from the clutch plate back. It does well mechanically back there. The only weakness is the engine, and electronics.
02-02-2016, 02:42 AM
#12
JK Freak
MetalDemon, Are you saying that the 3.6L is weak down low, or maybe you are talking about the older 3.8L? My experience with the 3.6L is dramatically different than your describing. Maybe its a gear ratio thing that skews my seat of pants opinion, my Willys Wheeler has 3.73 gears and I really never looked at what the 04 Grand Cherokee has for gears. I know driving the GC, it is no where near the low, mid or high RPM pull of the 2014 3.6L.
As far as electronics go, I'm not sure what you dislike, but all cars and trucks run essentially the same sorts of computer systems and they are all pretty reliable unless you have a freak. Most folks will drive 100K miles and never have a sensor issue. I rather enjoy the reliability of these newer vehicles. I hated carbs, points, distributors and the maintenance that came with them. I put fuel injection (ProJection) on my '71 Chevelle because I was tired of dealing with issues year after year.
I guess my confusion is that I see the 3.6L as a major step in the right direction for the Wrangler. It's down right fast in my 32" tire, 3.73 gear, 2-door JK. I wouldn't buy a 2012 3.6L on a bet though, a couple buddies of mine have been down the road of the cylinder head issue and they all had to play games with the dealers to get it taken care of under warranty. One of them went through it twice on the same engine.
As far as electronics go, I'm not sure what you dislike, but all cars and trucks run essentially the same sorts of computer systems and they are all pretty reliable unless you have a freak. Most folks will drive 100K miles and never have a sensor issue. I rather enjoy the reliability of these newer vehicles. I hated carbs, points, distributors and the maintenance that came with them. I put fuel injection (ProJection) on my '71 Chevelle because I was tired of dealing with issues year after year.
I guess my confusion is that I see the 3.6L as a major step in the right direction for the Wrangler. It's down right fast in my 32" tire, 3.73 gear, 2-door JK. I wouldn't buy a 2012 3.6L on a bet though, a couple buddies of mine have been down the road of the cylinder head issue and they all had to play games with the dealers to get it taken care of under warranty. One of them went through it twice on the same engine.
02-02-2016, 04:42 AM
#13
JK Super Freak
MetalDemon, Are you saying that the 3.6L is weak down low, or maybe you are talking about the older 3.8L? My experience with the 3.6L is dramatically different than your describing. Maybe its a gear ratio thing that skews my seat of pants opinion, my Willys Wheeler has 3.73 gears and I really never looked at what the 04 Grand Cherokee has for gears...
The 3.6l wasn't everything I could want in a Jeep engine, but it was at least enough engine to make it a fun and capable daily driver.
02-02-2016, 08:37 AM
#14
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Does any manufacturer make a kit to swap in a 4.0 stoker into a JK. A 4.7 stoker would make a nice replacement for the 3.6 in mine. I don't want a Hemi or a POS LS. I want bottom end torque, plus I have a few of them. The whole point is to rip out as much of the electronics, and nanny systems as possible. It would require me to make a new harness, but that wouldn't be bad. An OBD II emulator can take care of the emissions report where I live.
02-02-2016, 09:18 AM
#15
JK Freak
I see that there and I scratch my head. Short of a sports car, I'de race and put up a fight against any normal car or SUV. Calling a the 3.6 Pentastar a dog is a misnomer. I'd even say my JK is fairly heavy with engine/trans skid, fuel skid, EGR skid, Muffler skid, steel full width front and rear bumpers, 12K LB winch and Hi-Lift. There has to be an extra 500 lbs of crap bolted on, and I'm still ready to race from at any red light, any time! Maybe I have a factory freak that runs extra well?
02-02-2016, 10:37 AM
#17
Super Moderator
BTW, the LS conversions are drive by wire as well, but I'm sure the tune addresses any throttle lag.
02-02-2016, 03:02 PM
#18
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My whole point here is reliability. This JK sputters at least once a day, normally around 1600 RPMs with the pedal half way down when it does it. Yes, I do dislike the fly by wire. If I push it hard it doesn't do it, but then the MPG goes down to 12-13. It has plenty of power if I get on it, and row the shifter like a sports car with the RPMs up. Yes, it will smoke the 35's. I guess I am just used to having a vehicle I can trust not to leave me sitting someplace. At 55 years old, I have only had five vehicles in my life. The only other vehicle I had this much problem with was the only other new vehicle. I bought a new Cheby truck at 18, which had all kind of mechanical issues. Having been a diesel, and automotive mechanic for many years before I got tired of it. I do all of my own repairs, unless it is under warranty. I think my best bet will be to take the loss, and get something reliable.
02-02-2016, 03:26 PM
#19
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I had a newer Honda before getting my 3.6 jeep, and it too had drive by wire. The jeep is worse for sure. Almost enough to make me regret getting a manual.
02-02-2016, 04:01 PM
#20
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The fly by wire is difficult if you have another manual that doesn't have it. I didn't realize it was that bad till I bought my 1994 XJ 5 speed to back up the JK. My other 1998 XJ is an automatic. My son drives that XJ at college, about 2 1/2 hours away. If I go up to see him, I take the 1994 for reliability, and gas mileage. 21MPG is much better than 16MPG. Even though the 94 XJ has 3.55 gears instead of the 3.07 gears it came with.