Jeep Creep Off-Road Tech Questions Answered

Have a Jeep tech question for the Jeep Creep? Send an e-mail with your name, vehicle year, model and a detailed description of the problem to Jeep Creep at

Previous Jeep Creep Q&As:

December 2010

November 2010

October 2010

No Jeep recalls this month.

Cherokee Buildup
My name is Ryan, and I have a 1993 Jeep Cherokee. I am trying to get it off-road ready. I had an ‘86 Toyota pickup with a 3-inch body lift and 33x12.50 Goodyear MT/R tires, and I loved it. I’m trying to make my Jeep comparable to my Toyota’s off-road capabilities. Any suggestions would be greatly appreciated. I’m also wondering if I need lockers, and if I use a 4-inch lift kit, would 35x12.50 tires on 10-inch wide wheels fit?

My first suggestion would be a lift kit install. You have a choice between 2 inches, 4 inches, or 6 inches, with some even higher lift kits if you’re interested. I’d also stick with the Goodyear MT/R tires as well. Next, you’d want some lockers. Anyway, I’m involved with building a 1989 Cherokee XJ called Master ‘Kee. Here’s the link: http://www.off-road.com/jeep/project/project-master-kee-89-jeep-cherokee-build-52814.html

Follow the series if you want additional suggestions on a Cherokee build. With a 4-inch lift, 35s on 10-inch rims would just barely fit. You might need to cut some fender metal and/or spacers behind the wheels, depending on the lift kit. You won’t need lockers, but if you’re going with a lift and 35s, you’re going to want them in order to get over the more technical trails after the modifications.

XJ Wobble
I have a ‘98 Jeep Cherokee XJ with a 4.5-inch lift and 33x12.50x15 tires. My Rough Country lift included longer lower control arms. I am getting death wobble at 43 mph. I am going to replace the upper control arm bushings with poly bushings, which use the existing steel shells from the old rubber bushings. My question is, the bushing on the driver’s side on the top of the differential looks like it is only half way in the cast loop. Should I press the shell all the way in or is it correct to be centered and not in to the flange?
Bill Cusick

Center the bushing. I also suggest that you replace all of the rubber bushings with poly.

No Smoking Here
I need your help. I have a ‘93 Jeep Wrangler 6-cylinder. Lately, I have to be adding oil to the motor like 1qt a week. It is smoking bluish smoke and running sluggish. Do you think it’s going to run into a lot of money?
Silvia Javadiangilani

Sluggish engine and blue smoke sounds like rings to me, which means a complete engine rebuild. Do a compression check on the cylinders to make sure.

Sputtering Four-Banger
My ‘94 Wrangler with a 2.5L engine has loss of power, sputters, and backfires during first few miles until the check engine light comes on then it runs fine. I changed spark plugs, wires, cap, and rotor. I also changed TPS but nothing seems to work, it still does it. What could it be?
Kenny Reb
Jay, OK

You need to have someone read the engine’s computer code. Most chain auto parts stores have readers, so that shouldn’t be a problem. Once you get the read-out, do the changes necessary.

Auto-Tranny Troubles
I have a 2000 automatic Jeep Wrangler which isn’t shifting into gear properly (stalls or catches when in Drive). I also noticed that it is starting to overheat according to the coolant temperature and there is beginning to be a “burnt” smell after running it. We had a mechanic look at the transmission, and they said the fluid looked fine and that they didn’t notice any issues when driving it. Any suggestions or ideas on what could be causing this and what needs to be fixed?

Sure. Well, we first noticed the problems after shifting from 4-wheel drive back to 2-wheel after a snow storm - seems like it just wants to stall out now all the time, not shift into the right gear. We haven’t had it back in 4-wheel drive since then. The easiest way I can think to explain it is that you put it in drive and it doesn’t want to move for a little while, the RPMs rev up, and then it moves. Catches are rather random in timing - no set pattern, but most noticeable when you first start driving. The last couple of days the temperature coolant gauge has started increasing quite rapidly after even driving it just a few blocks, so we’re a little concerned about driving it. Please let me know if this helps or if you need a better explanation, as we would really appreciate any advice.

Christopher
Peoria, IL

You may have a tune-up problem that’s acting like a tranny problem. And I’m assuming the tranny fluid and coolant is not only at their full marks but have also been changed to provide new products?

‘47 Willys
I have a 1947 Willys PU truck. Although I’m keeping the exterior original, I do need to convert the engine either to a 6-cylinder or v-8 and trans to a daily driver (replacing the three-speed with an automatic). Which engine and trans would be best as far as marrying up with each other for ease of this conversion? I’m trying to keep in mind power as well as fuel economy. I’m a girl so yes I would like the best of both worlds, what can I say?
Tracie Erickson
South Bend, IN

What’s being a girl got to do with anything? You’ve got a ‘47 Willys truck with which you want to go wheeling and to work, ‘nough said! Besides, I’m somewhat envious—I love those trucks and wagons! In my opinion, your best bet would be a GM 4.3L V6 with a 700R4 automatic. Advance Adapters can not only provide all the parts you’ll need but also a book showing you exactly how to do the conversion. The engine/trans combo will give you performance and economy both on the trail and on the road.

Flattie Found
I am looking to buy an older, hopefully a flat fender, Jeep to use as an air show ground ops vehicle. I’ve found a 1950 CJ3A and the owner says the VIN is GB140511. How might I verify if that is the correct VIN/serial number and the Jeep is what it is supposed to be? I know a little about Jeeps and I’m pretty sure this is a 3A from the windshield. My real concern is if the serial number/VIN is correct so that I can register the Jeep in Indiana. When I checked websites about serial numbers, I didn’t think this number fits any of the data I found. I am just trying to do my homework.
Sweet Old Bill Foraker
Terre Haute, IN

MBs and CJ2a Jeeps have fold-down, fold-out, square-framed, 2-piece windshields. CJ3a Jeeps have a single-piece windshield and the frame is slightly more rounded at the upper corners. Both CJ models have the same flat-head four-banger, 3-spd transmission, T-case, 5.38:1 gears, and under-driver’s-seat 10-gal. gas tank. CJ3Bs have a much higher (about 4 inches higher) hood to accommodate the overhead valve engine. That’s a 3A. Pretty good shape for a 60-year-old Jeep. You’re going to love it! Just remember one thing: You don’t drive a flattie, you wear it. They’re small and tight. I shoe-horned a small block Chevy into my ‘46 CJ2a and we even took it on vacation in ‘68 to Moab and Yellowstone. And by “took it” I mean we drove it. Of course my wife and I were much younger and more limber in those days.

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 info available on this? I will be running 35-in tires soon. I am on a limited budget after spending so much on the vehicle. Is there a cost effective upgrade maybe a bolt on at a reasonable price? I continue to read articles on the weak front axle of the JK Rubicon. I bought the Rubicon because I anticipated the increased strength of the front Dana 44. Is it really that weak? What can I do to strengthen the axle or do I need to?
Rob
Rocky Ford, CO

I’ve seen catalogs offering 16” and 15” wheels for the JK, but I wouldn’t recommend going with smaller than the OEM 17” 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” rims.

I have over 30,000 miles on my ‘07 Rubi Unlimited. I haven’t had a problem with the front end, although my warranty did buy a new rear diff when the locker quit working. I have heard that the axles themselves are Dana 30 axles, so you might want to start there. Although I’d suggest that you wait to replace anything until you break something. If you live near Colorado Springs, go by the 4-Wheel Parts shop there and look at a Currie Dana 44 to see if there are any obvious differences in knuckle sizes and the sizes of the outers. Also, I suggest aftermarket wheels for the 35” tires with about a 1” outward offset difference than the OEM wheels (or 1-inch spacers with OEM wheels). I had to shim out the steering stops to avoid rubbing on the frame.

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

Previous Jeep Creep Q&As:

December 2010

November 2010

October 2010