Jeep Creep Q&A: Off-Road Jeep Questions Answered

Jan. 28, 2014 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 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. Send your Jeep questions to editor@off-road.com, Attn: Jeep Creep.

Previous Jeep Creep Columns
December 2013

November 2013

October 2013

13V-483: Chrysler is recalling certain model year 2014 Jeep Grand Cherokee vehicles manufactured January 8, 2013, through August 20, 2013. Due to a disruption of computer communications and loose alternator ground wires, the affected vehicles may experience random illumination of multiple instrument cluster warning lights, loss of cluster illumination and loss of anti-lock brake system (ABS) and electronic stability control (ESC) function. Because of these conditions, the vehicles fail to conform to the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 101, “Controls and Displays,” and No. 126, “Electronic Stability Control Systems.” A loss of ABS and ESC function reduces the driver’s ability to control the vehicle. Drivers would not be warned of brake system failures or any other failures which would be illuminated on the dashboard display. Either condition increases the risk of a crash. Chrysler will notify owners, and dealers will update the ABS and instrument cluster module software and tighten the alternator ground wire, free of charge. The recall began on November 19, 2013. Owners may contact Chrysler at 800-247-9753. Chrysler’s recall campaign number is N58.

13V-552: Chrysler is recalling certain model year 2013 Dodge Avenger and Chrysler 200, and model year 2014 Jeep Compass and Patriot vehicles equipped with 2.4L engines. Due to abrasive debris in the balance shaft bearings, these engines may have a loss of engine oil pressure, possibly resulting in an engine stall or engine failure. If the engine stalls while driving it may increase the risk of a crash. Chrysler will notify owners, and dealers will replace the engine balance shaft module, free of charge. The recall began on December 24, 2013. Owners may contact Chrysler at 800-247-9753. Chrysler’s recall campaign number is N52.

Building a CJ
I’ve read your recent answer where you list suggestions on how to order a new Jeep Wrangler and I really liked your options. Good job! But they don’t help me with my problem. I just got a really good deal on a 1984 Jeep Scrambler, but it’s completely stock. It hasn’t even been lifted yet, and as far as I can tell it still has the two-piece axles in the rear end. What would you suggest I do to the Scrambler? I’ll be driving it to the trails around home and maybe tow a camping trailer, so I need to keep it street legal. I also want to rock crawl. I’ll be trailering it to events farther away. I plan on taking about two years for the rebuild, so money shouldn’t be a problem. But I also want to be able to use it during the two years. In other words, if you had a large budget, what would you do to an ’84 Scrambler? And how would you do it so that it could be used between upgrades? By the way, the body is in really good shape. The 4.2 six runs okay, and the five-speed manual transmission works alright (although I think I’ll need a clutch in a few more months). I think it has 3.73 gears (one tag is missing and the other one is messed up so it’s hard to read).
Woody Rutledge
Corpus Christi, TX

Wow, Woody, a big budget, a stock Scrambler and a slick slate! That’s almost too much for a Jeeper to contemplate! In order to make it easier to follow my suggestions I’ll list them by number. Where possible, I’ll also list some manufacturers and/or retailers where the product is available (if the product is in short supply). If there are several suppliers, I won’t mention the names because an Internet search will give you any number of them. In addition, although the specific part for a CJ might differ from the same part for a YJ or a TJ—for instance, front springs (i.e., narrow leaf springs for the CJ, wider leaf springs for the YJ, and coil springs for the TJ)—if I suggest a lift kit, a body lift kit, or an engine transplant, the suggestion will work for all three models, just the specific part(s) will be different.

1. I’m assuming—since you say you’ll be attending events and doing some rock crawling—you’ll want larger tires, but I’ll get to that later. First, you should do what I do with every used car I’ve purchased. I change all the hoses, fluids, and belts so that I’m starting fresh. I also check the condition of the brake pads and shoes.

2. Secondly, you’ll need stronger axles, more clearance (fender, ground, and frame), and lower gears. If you’re going to use 37-inch or larger tires, you’ll want larger differentials than the OEM Dana 30 front and AMC 20 rear. You’ll want at least Dana 44 differentials front and rear; Dana 60s if you’re going to compete. However, I recommend a maximum of 35-inch diameter tires if you’ll be driving it on the street for any distances—you’ll get more miles per dollar than the larger tires and they’re easier on your running gear. For 35s you’ll need to do the following on a CJ: one-piece axles in the rear AMC 20 differential—this is one of the weakest points in the Jeep’s driveline—(several makers offer one-piece axle kits, such as Summers Brothers, Alloy USA, G2; check Morris 4x4, 4Wheel Parts, Quadratec, etc.). If the front differential doesn’t have free-wheeling hubs, you’ll need a pair; they will ease your highway travels. Also I recommend upgrading your front axles with stronger units such as RCV axles. Both OEM differentials should have strengthening trusses welded from the ends of the axle tubes over the pumpkin (see the photo below).

 

For gears, if you upgrade to a Dana 44 in the rear, I’d recommend 4.27:1 gear ratio. Unfortunately, 4.27 gears are not available for the AMC 20, so I suggest 4.56:1 gears, which is what I have in my ’82 CJ7. Many companies make 4.88 and even lower gears for the Dana 30/AMC 20 combination, but in my opinion the Dana 30 pinion gear for any ratio lower than a 4.56 would be too small to survive for long. Add lockers—selectable in the front Dana 30 and either selectable or permanent lockers in the rear—and you’re finished with the differentials.

3. Moving up the chain of power, the suspension is the next object of our attention. With a TJ or JK you can go quite high—6 to 8 inches—because of the long-arm suspension designs. Even with a YJ (with the wider front springs) you can find 6-inch lift kits, although you’d have to do some expensive and extensive changes to the drivelines if you go that high. Therefore, I recommend a maximum of 4 inches lift for any of the shorter wheelbases. With a Scrambler you could go with a 6-inch lift if you change the front spring shackle mounts to the 2-inch-wide springs you’ll find on a YJ—available through several suppliers. In fact that’s what I did on my Seven more than 20 years ago, and I’ve been enjoying a YJ 4-inch lift suspension ever since. Oddly enough, with the YJ leaf springs you only need to carry one spare spring set for an emergency “get home” repair because all four springs are the same width and length (although the pumpkin angle shims may be different, but it will get you home should you break a spring on the trail). Several suspension manufacturers offer 4-inch lift kits for CJs, YJs, TJs, and JKs, so you only need to shop for price and reputation. If you’re going to try some of the more technical trails, I also suggest leaf springs with “military” wraps. This means that there are double leaf wraps around each end of the spring to make it more durable. And don’t forget an extended-drop Pitman arm from the steering gear box and extended bump stops so you don’t bottom out the new shocks.

4. Tires and wheels: If you’re going to be rock crawling, you’re going to want an open, aggressive tread pattern. For 35-inch-diameter tires, I recommend getting a 12.50 size, which are available in 15-, 16-, 17-, and 18-inch-diameter wheels. If you can afford them, I’d also suggest bead-lock wheels, although I’m not aware of any bead-locks that are DOT approved for highway use. And 10-inch-wide rims work well with 12.50 tires just be careful of the offset of the wheel so it’ll clear your frame and/or body during very tight turns.

5. You may or may not have to extend the driveshafts with a lift. I’ve never experienced a problem with either driveshaft on the CJ7 but I’ve kept the U-joints well-greased. However, I strongly suggest a change to a 4:1 low range in the transfer case. Several manufacturers offer these kits, depending on what model transfer case your Jeep has, including Teraflex. A Dana 300 case comes from Jeep with a 2.79:1 gear ratio, while Rubicons (TJ and JK) have 4:1 low range from the factory. A 4:1 is much safer going downhill by controlling the Jeep’s speed. Going uphill can also be accomplished much slower with more control due to the improved gear multiplication.

6. Engine and transmission: I’m a child of the “fifties” which means I’m a V8 and automatic transmission fan. The torque advantage of a Chevy small block 350 cannot be overemphasized! Couple it with a GM TH350 three-speed automatic and I can idle over almost any obstacle, lock it in low for those extra steep and super loose downhill slopes so I don’t have to ride the brakes, and still have a ball with super-wide paddles in the Glamis dunes. It’s a great all-around setup, but I do have an alternative. One that several people I’ve spoken with on the trails think is the best of all worlds: a Chevy 4.3L V6 and a GM 700R4 automatic transmission. With a Scrambler, Woody, you have more than enough wheelbase to accommodate the longer transmission, and if you prefer a new engine to a refurbished used one, Summit Racing offers a crate 4.3L with 262 horses—which is interesting because that’s also the engines cubic-inch displacement (262 CID)—although you’ll need a donor motor for all the accessories and necessities like alternator, ignition system, fuel injection, etc.

7. Of course, you’ll need at least a 9,000-pound winch, full-cage roll bar, new seats and seat belts, and auxiliary lights. You may also want to upgrade the brakes with disc brakes instead of the rear drum brakes.
There you have it, Woody, my list of goodies for the complete CJ (or YJ or TJ).

Bleeding Stainless Steel Brakes
Several years I had a disc brake kit from Stainless Steel Brakes installed on my CJ. They’ve worked great for all these years. However, I recently changed my flexible brake hoses and bled all four brakes. But my pedal still feels soft and mushy. I no longer have the installation instructions so I can’t figure out if I’m bleeding the brakes right. I’ve been bleeding brakes for years with no problem but I can’t figure these out. Can you help me? If not, I’ll have to find out how to contact Stainless Steel Brakes or find a shop around here than knows Jeeps.
Frank Magnum
Oklahoma City, OK

Stainless Steel Brakes (http://ssbrakes.com) uses a GM-style caliper (see photo) from a pickup’s front axle. And even though it’s equipped with two bleeder valves, you have to use the lower valve when the caliper is mounted. What you must do is remove the rear calipers, use the proper size block of wood between the brake pads (to simulate the disc), and bleed the brakes in the normal fashion while holding the calipers upside-down. This puts the previously mentioned valve on top, which allows the air to escape the lines. Remove the wood and reinstall the calipers.


Rotopax Containers
Where can I get those Rotopax holders that mount to the PSC rear bumper? I cannot find them on the RRM website.

I wish you’d left an address and name. I’m afraid you’ll have to build your racks for the Rotopax (http://rotopax.com/Pack-Mount.html) containers. However, you can buy the locking mounts from Rotopax, Amazon, 4Wheel Parts, etc. You would then mount them on the racks to hold the containers in place.


Bad Ignition

I have an ‘85 CJ7 with a 4.2L engine and manual tranny. The engine spins over but will not start. Sometime it hits once I let off the key. I have changed the ignition switch control module, the coil, the distributor cap, the rotor, and the distributor. Help!! I am a first time user of your site.
Steve

Check for voltage on the plus (+) side of the coil when cranking. If it has voltage, measure how much, then check for pulsing voltage on the minus (-) side of the coil when cranking. It could also be a possible bad coil. Look in a repair manual for a wiring diagram for the proper ignition circuit during cranking. (I once had a tachometer that caused this one time—rare but possible.) It should have at least 10 volts at the coil during cranking. It could also be a bad starter solenoid or bad wiring from the ignition side of the solenoid (on one of the two small posts). If it has only one small post then cold crank voltage is through the ignition switch.

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.

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. Send your Jeep questions to editor@off-road.com, Attn: Jeep Creep.

Previous Jeep Creep Columns
December 2013

November 2013

October 2013


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