Jeep Q&A: Wrangler, Cherokee, Grand Cherokee Tech and More

Nov. 27, 2013 By Jim Brightly
In your Jeep Creep questions, please list your first and last names, your hometown, and your state/province/country, so that we can publish that information here. If you donít provide this information, we may not be able to publish your question and answer. Donít forget to be as complete as possible with the description of your Jeep and its problems, too. Send your Jeep questions to editor@off-road.com, Attn: Jeep Creep.

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October 2013

September 2013

August 2013

PLEASE NOTE: Due to a lapse of Federal Government funding, NHTSA is unable process safety defect complaints after close of business September 30, 2013. Consumers can continue to file complaints, but they will not be evaluated by NHTSA staff until funding and services are restored.


YJ Advice
I just bought a í93 YJ Renegade with a 4-inch lift, 33-inch tires, and 3.07:1 gears. I have to keep it highway ready because itís my daily driver, but I also want it more trail worthy. Can you give me some advice on improving my chances on the trail?
Craig Holden
Yuma, AZ

Your question triggered my four-wheeling reflex. While Iíd like to see you go with lower gears, taller tires and some traction aids in the differential department, I think your first step would be adding a Terraflex 4:1 low range. Your current low range is approximately 2.7:1, so the added gear multiplication will aid you off-road without changing your on-road ability. And with the NP231 transfer case, youíll still be able to flat tow the Jeep should you ever wish to do so. If you also go with a slip-yoke-eliminator kit, youíll also have to change your rear driveshaft. You can either buy a new one, or have an XJ front driveshaft cut down to fit your Jeep, which is much cheaper. By the way, stick around here at Off-Road.Com because we have just such a conversion in the works. It should be posted in the next month or two.

Flutter Sputter
I have a 1988 YJ 6 cylinder. The problem Iím having is that it will idle good, but going down highway it will lose power and start to go dead. Sometimes putting my foot on the brake and revving engine will keep it going but it must be kept at high rpm. It quit on me this past weekend. I had it towed home, and after the wrecker left I got in tried to start the Jeep. It fired right up. Itís not the first time this has happened. Last time it happened I replaced the carb and it has been running good for almost two years. It has gas going all the way into carb. I pulled the exhaust manifold and intake off and wrapped exhaust manifold with a high temperature wrap all the way to muffler. Reinstalled all components and the Jeep ran fine. I think the exhaust was running so hot that gas was dissipating in the intake. Jeep originally had muffler and exhaust wrapped but due to exhaust having a blowout and replacing the Flowmasterís muffler, the wrap was never reinstalled.
Phillip
Florence, AL

The problem is somewhere in your fuel system. Either the tank isnít venting properly or the pickup tube is clogged. You could also have problems with the fuel pump or the filter. Start at the engine and trace the fuel line backward, checking fuel delivery at each connection. BE CAREFUL and have a container ready to collect the expended fuel. You donít want a fire!

Axle Switch?
Can I swap axles in a 2008 JK with 2004 TJ Rubicon axles? Iím looking to utilize the lockers and the Dana 44 differentials.
Jessie
Antlers, OK

Absolutely not! The JK is several inches wider than the TJ so the differentials wouldnít even begin to fit unless you lengthened them, and that wouldnít be cost effective in my opinion. Your best bet is to buy a JK Rubicon in the first place.


Headlight Restoration
I own a 2007 JK Unlimited, and the headlights have a heavy fog coating that I cannot get off. It causes hard visibility when driving at night. Living in Tucson with the blowing sand and dust has probably caused it.
Ben Schwimmer
Tucson, AZ

There are a couple of ways to restore your headlight lenses. One of our writers on Off-Road.com wrote a story about Meguiarís PlastX, which is designed to restore clarity to cloudy headlight. Iíd try that solution first, as itís the cheapest options. Another method can be found at a local airport. Itís called airplane canopy restoration compound. It is labor intensive and requires several sandings with very fine sandpaper (instructions come with the compound). The second suggestion is 3M Headlight Lens Restoration System 39008. It is also a compound and requires sanding with an electric hand-drill, but is said to be much less labor intensive. You should be able to find it at almost any well-equipped auto parts store.


Death Wobble Suggestion
So, I have a 2000 Grand Cherokee with a 3.5-inch lift. Iíve had the ďdeath wobblesĒ a few times, almost crashed into a center divider on the freeway. In fact, they have lost me a couple of dates. Anywho, I have replaced the control arms (top and bottomóthe bottom ones are now heim joints), track bar, sway bar, tie rod ends, tires (twice), wheel alignments (more times than I can count), dynamic wheel balancing, thicker steering fluid, new coil springs, and Fox 2.0 shocksóin other words, pretty much everything. What ended up solving this issue? The damn brake rotors. After reading a couple of these articles, I bought new ones and itís so much smoother! Everything else helped, too, I suppose. If I get the wobbles again, Iíll be back with questions.
Craig
Corona, CA


YJ Heart Donor
I have a 1988 Wrangler with the 4.2 engine. I am very interested in swapping the head to the 4.0 head, which is the engine my parts Jeep has. Is it really worth the swap? Or should I just run the 4.0? If I do the swap, I would also like to use the EFI off of the 4.0. Is there anything I should watch out for? And also would I need to tune the 4.0 computer at all? Both Jeeps are complete vehicles. Iím pretty new to Jeeps and computerized vehicles. But my dilemma is that the 4.0 has the wiring harness for an automatic transmission. And that transmission is junk. I still have my old Peugeot five-speed in my Jeep currently. Iíve heard my transmission isnít the best but it works and itís a manual so Iím happy with it (for now). What I have to work with is one complete 4.2 (not in my Jeep) and one complete 4.0 (in my parts Jeep, a Ď92 Wrangler) and a 4.2 with a blown top end (currently in my Jeep). Now Iíve been told that my transmission should bolt up to the 4.0 but the engine would not start without the sensor in the bell housing.
Cletus
Concord, NH

If you have a complete 4.0L donor engine thatís running well, Iíd swap the entire engine. Just make sure you include the under-dash computer as well to run the EFI. If youíre worried about the sensor, you can always have the computer updated by a well-equipped shop.


Wrangler Wheels
What is the smallest rim which can fit on a JK? I am told that the calipers can be ground down. Is there any information available on this?
Rob
Rocky Ford, CO

Iíve seen catalogs offering 16-inch and 15-inch wheels for the JK, but I wouldnít recommend going with smaller than the OEM 17-inch wheels. You might be able to grind down the calipers, but the brakes also need air circulating around them to keep them cool during heavy use in traffic or on a technical trail. If they overheat, they could cause problems such as grabbing, not holding, accelerated wear, etc. Stick with at least 17-inch rims.

As usual, each month, Iím shouting out a huge THANK YOU to Paul Schupp at Rock Lizard 4x4 in Kingman, Arizona, for his invaluable assistance in answering many of the Jeep Creep questions.

In your Jeep Creep questions, please list your first and last names, your hometown, and your state/province/country, so that we can publish that information here. If you donít provide this information, we may not be able to publish your question and answer. Donít forget to be as complete as possible with the description of your Jeep and its problems, too. Send your Jeep questions to editor@off-road.com, Attn: Jeep Creep.

Previous Jeep Creep Columns
October 2013

September 2013

August 2013

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