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 don’t provide this information, we may not be able to publish your question and answer. Don’t forget to be as complete as possible with the description of your Jeep and its problems, too.

No Jeep recalls this month. See all of the posted recalls at www.odi.nhtsa.dot.gov/cars/problems/recalls/recallsearch.cfm.—Jim Brightly

T-Case Conundrum

I have an odd question for you. We know what type of transfer case goes to our 1989 Jeep Cherokee. The ratio and all that (got the tag). But my question for you is can any transfer case work? My husband disagrees with me, but if it matches the ratio, splines and all, how could it not work? We found a transfer case for $200. I am a little hesitant with the buy because, yes, it comes from a salvage yard from a vehicle identical to ours, but with no guarantee that is the rub. If you could answer that for me I would greatly appreciate it.
Gina
Kentucky

I’m not sure what T-case you’re talking about, but if the driveshaft yokes match and it bolts up to your tranny, it should work fine. Since the information you’re giving me is not complete, I will say you may have to massage the T-case mounting and shifter, though.

Waggy Wheeler

I have a 1968 Jeep Wagoneer with the 327 GM motor, and some dummy before I got it put a two-barrel carb on it. So where could a person find a four-barrel (not an aftermarket carb) for my motor? The intake has the round holes, not the oblong ones. The Jeep also has the lockout front hubs, and it is an automatic transmission. Most of the vacuum lines were burnt off from a carb fire, so I need to know where to replace the new ones. How could I find a diagram of this?
Larry VanScoy
Baker City, OR

First of all, congrats on your Jeep choice—I owned a ‘65 Waggy with a Buick 350 in it so I know you’ll really enjoy it. For the vacuum lines, you need to go to the websites of 4-Wheel Hardware or 4-Wheel Parts and order the maintenance manual for your particular model. The manual should give you the diagram. Many rigs also had a diagram sticker on the radiator cowling, but due to the age of your Waggy it may have worn off. As far as the four-barrel carb is concerned, you’ll have to let your fingers do the walking and call all the junkyards in your area. I’m thinking any four-barrel from a late-’60s Chevy small block V8 should work, but take a to-scale diagram of the intake with you to make sure the carb will fit before you buy. Do you have a question about the hubs?

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Cherokee Clunks

When I start my Jeep—‘96 Grand Cherokee Limited—and back up (with the steering wheel turned quite a bit), this weird/loud clunk happens. Someone told us it was our right front axle, but we replaced it and still have this problem. What could it be? Need I worry?
Hayden
Oviedo, FL

You have no need to worry in the short term; however, you should get it taken care of. It sounds like you’re having problems with your suspension’s “soft” bushings (either rubber or neoprene). You should check the bushings in your trackbar, sway bar, or the links—wherever you have bushings. Depending on mileage, you might want to replace all the bushings with new neoprene bushings and have the alignment checked afterward.

Backfiring in the OC

I have a ‘91 YJ. The problem I am having is that at almost exactly 3,000 rpm and almost all the way up to 3,300 rpm the engine starts to cut out, backfire, etc. I either have to decelerate or floor it to get past that rpm range. What would cause this?
George
Tustin, CA

Go Tillers! You’re not giving me enough information, George. There used to be some really good tune-up shops in the OC, call around until you can find someone who’ll put your Jeep on the ‘scope. Someone on-site can diagnose something like this much easier.

Dana 20 vs. Dana 44

I had the axle shaft come out of my 1989 Jeep Grand Wagoneer. I am on a tight budget. I have a rear differential from a 1985 Jeep Grand Wagoneer. I believe mine is a Dana 44 and the ‘85’s is a Dana 20. The 20 will bolt in place but is it a good choice or should I find/fix the 44? I have checked the gear ratios and the Dana 44 is 3.31:1 and the Dana 20 is 3.23:1. This is based upon the number tags on the differentials. I also manually checked by turning the input and counting the revolutions. The count is close enough that they have not been altered. I plan to use the Dana 20 until I can rebuild the 44 and put it back. This was so I can still drive the Jeep. I just won’t push it hard.
Jim Davenport
Omaha, NE

First of all, your replacement differential is an AMC 20, not a Dana 44. The 44 has bigger axle tubes and shafts, single-piece axles, and more gear ratios are available. The 20 has a larger pinion shaft, weaker axle tubes, and two-piece axles. I don’t think the ratios match close enough to use in 4WD. If you’re going ahead with the 20, I wouldn’t use it in anything but 2WD. You’re taking a chance on blowing your T-case if you do. My answer would depend upon how hard you use your Wagoneer. If you’re just going to drive it on the street and a few dirt roads, then by all means install the AMC 20. If you enjoy trail riding, rebuild the Dana 44—it would be much cheaper in the long run.

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Knock & Roll

My girlfriend ran over some bumps approaching a toll booth in her ‘05 Jeep Wrangler and now there is a knocking noise. The noise appears to slow down as you reduce your speed. Clutch seems to be fine and the brakes are working fine. Could she have shaken something loose in the tranny or something else?
James Van Roy
Mesquite, TX

You’re not giving me enough information. If it’s not a U-joint, loose exhaust system, or a broken shock mount, you might need to take it to a shop. Someone on-site can diagnose something like this much easier.

2WD XJ Lift

I have a stock ’96 2WD XJ (that’s right, my little monster is only 2WD), and I recently acquired a set of 31-inch 10.50 tires. I really want to put these tires on my Jeep and I want to know the minimum lift that would be required to fit them and still have space for articulation and minimal chance of rubbing? I do take my XJ down some pretty rough roads up in the hills where I live, and I don’t want to have my fenders cutting into my tires while I am flying down rough dirt roads.
Tyler
Fruita, CO

I’d say the minimum lift would be 2 inches, however, if available, a 4-inch lift would be better.

Broken Nut

I have a 2005 Unlimited Rubicon. My mid-skid plate attached to my transmission mount under body plate is loose. One of the frame nuts is broken, and it’s a box frame. How would you approach this fix since there is no access hole?
Troy Devault
Orfordville, WI

The easiest method would be to use a new nut and weld it over the existing hole in the frame (align it so the bolt goes through both nuts). The more difficult method would be to use a piece of scrap steel matching the frame’s material, drill the appropriate-size hole, weld on another nut, cut out a piece of the frame around the broken nut, and weld in the new piece.

More Mopar Power

I have a 2000 Jeep TJ with the 2.5L four-banger and I’d like to squeeze a little more power out of it. I’ve already switched out the factory air box for an Airaid system, added a Banks header, swapped the throttle body for a 62mm, and replaced the original fan with an electric. I am looking at replacing the stock exhaust with either a Banks Stinger or a Flowmaster cat-back. Do you have any other tips or suggestions?
Dobey
Pensacola, FL

It sounds to me like you’ve already done about as much as you can to the four banger. Let’s face it, a four holer can only produce so many ponies before you need to double the bang for your buck—a V8 or at least a six-pack—and you didn’t indicate what you want the additional power for. Is it for off-road or on-road use? For off-road use, you could change to deeper differential gears.

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Wobbly U-joints

I have a ‘91 YJ with a spring-over lift. I built an axle-wrap bar from the pumpkin to the frame and replaced motor mounts and transmission mounts. My problem is I have a wobble in the drivetrain that is taking out U-joints. I would really like an opinion or two on this major problem and maybe a solution.
Roland
Kamloops, BC, Canada

My folks used to have 30 acres near Kamloops on the Skukumchuck River, near Kimberly - good wheeling country. Your problem is in the driveshaft. It may need balancing. Or you didn’t align it properly when you installed it. The U-joints have to be aligned, so you need to reclock the slip joint so that the U-joint stars match up. You may also want to look into shimming up the front of the differentials to reduce the angles. You might also want to look at the Tom Woods Driveshaft website (www.4xshaft.com); loads of DIY information on the site.

Flattie Fun

I’ve got an L134 engine that has “SPECIAL” casted into the block on the left rear lower side just above the oil pan. It also has “WO” stamped into the boss just above the coil mount. Any idea as to what or why this is? The engine was in a 1947 CJ-2a; it’s now in my ‘51 CJ-3a.
John Waddle
Sabina, OH

This really brings back the memory of my first Jeep—a CJ-2a that I bought in ‘64 and sold in ‘68 after dropping in a Chevy V8—but that was 40 years ago. I’m just guessing here, but I think the “WO” could have reference to the engine’s point of manufacture. I have no idea what “SPECIAL” signifies, unless it has something to do with the engine being a civilian engine and not a military one (the MBs had very, very tight weight restrictions, which resulted in its extremely small transmission compared to the CJ’s tranny). You should be able to find some websites dedicated to the Flatties on which you’ll find the answers.

Size Does Matter

I’m looking to put larger tires on my Wrangler YJ. It’s all stock except a 4-inch Rough Country suspension lift, and I’m wondering what size tires I could run without having to change gearing or anything?
Rick Vandyke
Manton, MI

Without knowing which engine and/or tranny you’re running, I can answer that only in one way. I wouldn’t go over 33 inches. If you go to lower gears, say 4.10 or 4.56, you could go with 35-inch tires such as I have on my CJ (see my blog about the Goodyear Wrangler MT/R with Kevlar tires that were introduced in Moab last spring).

Flame Thrower Add-on

My friend has a 2008 Wrangler. He wants to take his cat converter off so we can install a Flame Thrower kit, and I was wandering if the O2 sensor can be bypassed so there is no engine trouble or check engine light. Also, do you have any tips on installing Flame Thrower kits?
jmarc347
Elkridge, MD

Is your friend aware that doing this may very well void his lifetime warranty? It’s also likely to screw up his engine’s computer. And it may not accomplish anything other than that. I recently installed a cat-back exhaust, intake air filter kit, and computer chip to my ‘07 Rubi with negligible effect (about a 5-pony increase). And the Jeep won’t pass emissions any longer as well. Personally, I wouldn’t do it.

As usual, each month, I’m 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.