MODIFIED TECH FAQ - Answers to the Questions Every Newbie Has

MODIFIED TECH FAQ - Answers to the Questions Every Newbie Has

Results 1 to 7 of 7
  1. #1
    JK-Forum Founder
    Join Date
    Jul 2006
    Location
    Laguna Niguel, CA
    Posts
    36,535

    Question MODIFIED TECH FAQ - Answers to the Questions Every Newbie Has

    Click on the links below to find answer to the questions you have regarding the Jeep JK Wrangler:

    SUSPENSION

    WHEELS & TIRES

    AXLES, GEARS & DRIVETRAIN

    BUMPER & ARMOR

    BODY MODIFICATIONS

    TROUBLESHOOTING



    Last edited by Ryan0260; 09-06-2013 at 01:03 PM.

  2. #2
    JK-Forum Founder
    Join Date
    Jul 2006
    Location
    Laguna Niguel, CA
    Posts
    36,535

    Default

    SUSPENSION QUESTIONS

    Q: What size lift do I need to get in order to fit 33" Tires?
    A: Stock will work but a 2" budget boost will be a perfect fit.


    Q: What size lift do I need to get in order to fit 35" Tires?
    A: I would recommend a minimum of a 2.5" budget boost but a 3" lift would be a better fit. You can also install a 2" budget boost and 1" body lift to get you there as well.


    Q: What size lift do I need to get in order to fit 37" Tires?
    A: I would recommend no less than 4" of lift to clear 37's.


    Q: How can I level out the factory rake that my JK has?
    A: Installing a set of 3/4" coil spacers will help the front end of your JK to sit more level with the rear.


    Q: I just installed a heavy duty bumper and winch and now the front of my Jeep is sagging. Is there any way to help regain the height that I lost?
    A: You can install a set of 3/4" coil spacers to help make up the difference. Or, if the manufacturer of your lift offers a set of heavy duty front coils, you should consider installing a set of them instead.


    Q: What is a 'BB' or budget boost?
    A: A BB or budget boost is a basic 2"~2.5" suspension lift that is achieved through the installation of inexpensive coil spacers. These spacers are typically made out of polyurethane pucks that are 2"~2.5" thick and are installed on top of your Jeep's coils. Some kits have spacers that are taller up front and shorter in the rear to help level out your Jeep's factory rake.


    Q: What are coil spacers?
    A: Coil spacers are pucks typically made out of polyurethane and are designed to be stacked on top of your Jeep's suspension coils and come in varying thicknesses such as 0.5", 0.75", 1.75", 2" or 2.5". Smaller spacers are typically used to level sagging caused from the installation of a heavy bumper and/or winch and taller spacers are often used as an economical way to give you a small lift.


    Q: What is Caster? How much do I need?
    A: Caster is the angle upon which your front axle sits at in order to help keep your Jeep driving straight. Positive caster, which is what you want, will cause your axle to sit in a way that your pinion shaft will be dipping ever so slightly towards the ground. Too little or even negative caster angle can cause your Jeep to wander and feel 'flighty' or 'darty' as I've heard some people call it. From the factory, your JK will have +4.2 of caster and if you lift it and install larger tires, you will need to increase this amount to help compensate for the modifications. At 3"-4" of lift, I have found that +6 of caster will do wonders to help improve the handling of your Jeep JK Wrangler but, if you're running 5.13 or higher ratio gears, you will most likely encounter drive line vibrations.


    Q: Do I need a new steering stabilizer now that I've lifted my Jeep JK Wrangler?
    A: If you have your suspension and steering dialed in, no, you will not need a new steering stabilizer on your lifted Jeep JK Wrangler.


    Q: Why do I need an adjustable front track bar?
    A: After installing a lift, your front axle will shift over to one side and an adjustable front track bar will allow you to reenter it.


    Q: Do I need an adjustable rear track bar?
    A: No. You will be just fine installing a track bar relocation bracket to reenter your rear axle. However, I would highly recommend that you install one that drops from the frame mount and NOT one that attaches to the axle mount. Axle mount brackets have been known to break the factory mount.


    Q: Will installing a lift void my warranty?
    A: No, it shouldn't. In order for your dealer to deny repairs to a break on your Jeep, they would need to prove that the damage was caused specifically by the lift. Having said that, your dealership can "flag" or place a restriction on your Jeep and this will in effect make it very difficult to have warranty work done. For more information on this, please click on the link below:

    https://www.jk-forum.com/forums/show...Lift-Your-Jeep


    Q: Do I need to buy new shocks if I'm just installing a budget boost?
    A: Unless you are buying a kit that comes with shock extensions, it is highly advisable to install a set of new longer shocks.


    Q: Do I need to install bump stop extensions?
    A: Yes. Bump stop extensions are designed to prevent the over compression of your coils and are absolutely necessary. Bump stop extensions can also help prevent the rubbing of fender flares at a full stuff as well as the bottoming out of shocks.


    Q: What size bump stop extensions should I install with my lift?
    A: Typically, you'll want bump stop extensions that are approximately as tall as the lift you just installed on your Jeep. In other words, if you lift your jeep 2", you'll want bump stop extensions that are about 2" tall. Now, I do say 'typically' as this is just a guide to follow and not necessarily a rule. Depending on the actual height of the coil, thickness of the wire used and the amount of winds it has, the rules can change.


    Q: What are all the components that I will need with a 3" lift?
    A: On a 2007-11 JK, at bare minimum, you should have a set of 3" coils, bump stop extensions, longer shocks, rear brake line extension brackets, new longer rear sway bar links (factory links can be installed up front), adjustable front track bar and rear track bar relocation bracket. Optimally, I would recommend adjustable front upper and lower control arms as well as they will help you set your caster to the appropriate angle it needs to be. Also, if you have a 2-door, adjustable rear upper control arms and a new double cardin U-joint style drive shaft would be highly advisable.

    On a 2012-Up, you will want to install a new front drive shaft regardless if you have an automatic or manual transmission. Assuming you install new, longer shocks with your lift, the extra droop you will see at a flex will cause the slip shaft boot on the drive shaft to tear. However, that is just one problem you will encounter. Even if you install exhaust spacers or relocate the cross over, the CV boot at the output shaft will be sitting at a significant state of pinch and this will cause it to fail prematurely.


    Q: What are all the components that I will need with a 4" lift?
    A: For a 4" lift, you should have a set of 4" coils, bump stop extensions, longer shocks, extended brake lines, longer sway bar links, adjustable front track bar, adjustable rear track bar, front and rear track bar relocation brackets, dropped pitman arm, adjustable upper and lower control arms front and rear and new double cardin u-joint style drive shafts.

    On a 2012-Up, you will want to install a new front drive shaft regardless if you have an automatic or manual transmission. Assuming you install new, longer shocks with your lift, the extra droop you will see at a flex will cause the slip shaft boot on the drive shaft to tear. However, that is just one problem you will encounter. Even if you install exhaust spacers or relocate the cross over, the CV boot at the output shaft will be sitting at a significant state of pinch and this will cause it to fail prematurely.


    Q: Why do you disconnect your front sway bar links?
    A: Disconnecting your Jeep's front sway bar links will allow your front axle a greater amount of articulation or flex on the trail. The more your axle can articulate, the more you can keep your tires on the ground even in severely uneven terrain and this will provide greater stability and traction.


    Q: What are 'discos' or sway bar link quick disconnects?
    A: Sway bar link quick disconnects are aftermarket links designed to make disconnecting and reconnecting your front sway bar links easier and faster.


    Q: Do I need to disconnect my rear sway bar links?
    A: No. You do not want or need to disconnect your rear sway bar links. Your rear sway bar is made out of a much narrower bar and is much softer so it will allow for plenty of unobstructed articulation while providing stability you want.


    Q: Are there any write-ups on how to install a lift on my Jeep JK Wrangler?
    A: Yes, click on the link below to see all the Project-JK suspension lift installation write-ups:


    Q: I just installed a lift on my JK. Do I need an alignment?
    A: Due to the design of the new JK steering system, your toe-in will not change after installing a lift. If your lift did not come with adjustable upper or lower front control arms, you will not be able to adjust your caster angle. If you kit came with cam bolts, I would NOT recommend installing them to get your caster set as they would require you to notch out your lower control arm mounts and make them into slots (a mod that is not easily reversible). And, in my experience, it is very difficult to keep the bolts from loosening up. So, with all that said, the only thing an alignment shop will do for you is reenter your steering wheel and you can do that in your driveway with a 15mm wrench and 5 min of your time:

    Now, if your lift kit did come with adjustable front upper and lower control arms, you can set your JK's caster following the instructions found towards the bottom of the same write-up.


    Q: I just installed a new suspension lift, why is my ride harsh, stiff or rough?
    A: Assuming you installed new tires at the same time as your lift, there is a good chance that your tires have been inflated with a PSI that is too high. For optimal comfort and even tire wear. you should not run the recommended PSI listed on the sidewalls of your tires. Typically this will be way too much. On average for a 33" tire, I would recommend that you run your tires at approximately 28-30 PSI. For a 35" tire, I would recommend running approximately 26-28 PSI. For a 37" tire, I would recommend approximately 24-26 PSI.


    Q: What are 'twin tube' or 'hydro' shocks?
    A: The twin-tube design is the most common and often times the least expensive. These are the ordinary shock absorbers that typical passenger cars and trucks use, and they are widely available at car dealerships, auto parts stores and repair facilities. As the name implies, in a twin-tube shock, there are two actual tubes – one the outer shock body and the other a cylinder inside in which the piston moves. Tiny holes or orifices in the piston as well as special valves between the inner and outer tubes restrict the flow of oil to control wheel motion.

    The limitations of twin-tube shocks become apparent when they are used over very bumpy roads. In this case, the rapid motion of the piston can cause the oil to overheat and to foam, reducing the shock absorber's ability to control wheel motion. The result is a ride that becomes increasingly sloppy, especially when traveling over a washboard surface. Heavy-duty twin-tube shock absorbers are usually stronger, with more robust piston shafts and mounting points, and they may use oils that are more resistant to foaming, but ultimately they still have the same limitations.

    - Kevin Clemens, Mobil 1 Racing


    Q: What are 'mono tube' or 'nitro' gas filled shocks?
    A: The heat generated in the twin-tube shock tends to get trapped within the walls of the shock absorber body, reducing its effectiveness in controlling wheel motions. The mono-tube shock absorber uses a piston traveling within a single tube that is exposed more directly to the air. The general advantages and disadvantages of this design are:

    • By getting rid of heat more easily, mono-tube shocks are less susceptible to overheating on rough roads.
    • They are more expensive to manufacture however, and the tolerances must be higher and the seals better to keep the oil inside the shock body.

    To prevent foaming and bubbles in the oil, which degrades shock-absorber performance, a gas-filled mono-tube shock has a chamber of high-pressure nitrogen above the oil chamber. This high-pressure gas makes it difficult for bubbles to form in the oil, even when the shock absorber moves in and out very quickly, as it might while traveling rapidly on a very rough or washboard road.

    Gas-filled shocks are expensive, since they require strict manufacturing tolerances, but they are very resistant to fade and consequently are popular in off-road racing and rallying. Gas-filled shocks, by the way, are not the same as "air shocks" which use an air chamber separate from the shock oil. An air shock is actually an air spring that raises or lowers the vehicle when air is added or removed through a valve.

    - Kevin Clemens, Mobil 1 Racing
    Last edited by Ryan0260; 09-06-2013 at 01:05 PM.

  3. #3
    JK-Forum Founder
    Join Date
    Jul 2006
    Location
    Laguna Niguel, CA
    Posts
    36,535

    Default Wheels & Tires

    WHEELS & TIRES

    Q: Do tires measure up exactly to what is listed on the sidewalls?
    A: No tire measures up to what is listed on the sidewalls. Most tend to come up way short of what is listed. Having said that, when discussing lift kits and how big of a tire you can run, you should ONLY go off of what is listed on the sidewalls and NOT the actual size of the tire. ALL lift kit/tire size discussions revolve around advertised tire size and NOT their actual size.


    Q: What is the biggest size tire I can fit on my stock Jeep JK Wrangler?
    A: The largest tire size that the factory recommends is a 255/75R17 (which comes standard on Rubicon models) or a 32x10.50. However, there are many Jeep JK Wrangler owners who are currently running as big as 285/70R17 or 33x10.50's with little to no rubbing issues. PLEASE NOTE: When discussing tire size, DO NOT take into consideration what the "actual size" of the tire is but rather, just what is listed on the sidewall.


    Q: What is the biggest size tire that I can I fit with a 2.5" Budget Boost?
    A: 33" without any problems and 35" tires with only minor rubbing at a full flex. Depending on how wide your tires are, you may experience some rubbing at a full turn especially if you did not install an adjustable front track bar and/or are still running factory wheels which have 6.25" of back spacing. PLEASE NOTE: When discussing tire size, DO NOT take into consideration what the "actual size" of the tire is but rather, just what is listed on the sidewall.


    Q: What is the biggest size tire that I can fit with a 3" lift?
    A: 35" tires and depending on what lift kit you have, you may still experience some minor rubbing up front at a full flex and when turning. PLEASE NOTE: When discussing tire size, DO NOT take into consideration what the "actual size" of the tire is but rather, just what is listed on the sidewall.


    Q: What is the biggest size tire that I can fit with a 4" Lift?
    A: 37" tires but you will need to trim the rear corner of the rocker pinch seam and you may still experience some minor rubbing at a full flex. PLEASE NOTE: When discussing tire size, DO NOT take into consideration what the "actual size" of the tire is but rather, just what is listed on the sidewall.


    Q: Will 15" Wheels Fit on my JK?
    A: Most steel ones will fit without any problems and depending on the thickness of the wheel most aluminum ones will as well. The only thing you really need to make sure is that the wheel clears the brake calipers.
    https://www.jk-forum.com/forums/modified-jk-tech-2/15-x8-rims-17449/


    Q: What back spacing will I need on my wheels in order to clear 12.50 wide tires?
    A: I would recommend that you do not exceed 4.75" of back spacing and even at that, you may still have some minor rubbing up front at a full turn. Also, I would recommend that you do not go any less than 3.75" as anything less would cause your tires to stick out very far past the fender flares. Any back spacing within this range should work out great. PLEASE NOTE: When discussing tire size, DO NOT take into consideration what the "actual size" of the tire is but rather, just what is listed on the sidewall.


    Q: What is backspacing?
    A: The distance measuered from the mounting surface of your wheel to the outside edge of the rim - see diagram below.




    Q: What are wheel spacers?
    A: Wheel spacers are rings measuring 1.25"~1.5" thick, are typically made out of billet aluminum and are designed to be sandwiched in between your Jeep's axles and wheels. By installing wheel spacers, you will effectively reduce the amount of back spacing your wheels have allowing you to install wider than stock tires without having to replace your factory wheels.


    Q: Are wheel spacers safe to use or do they cause extra stress on your axle or wheel bearings?
    A: High quality wheelspacers, the kind that bolt up to your axle first are no more dangerous or cause any more stress to your axles then would a wheel with less backspacing. Anyone who tries to tell you otherwise doesn't know what they're talking about and I have yet to hear a single good or specific explanation as to exactly how they are worse. Just to be clear, the cheap-o spacers (the kind that you can get at PepBoys and are sandwiched between your wheel and axle using the existing wheel studs) are in fact EXTREMELY DANGEROUS. These cheap-o spacers leave little thread for your lug nuts to hold onto and can fail. DO NOT USE THESE!


    Q: On the road, what PSI should I be running in my tires?
    A: For optimal comfort and even tire wear. you should not run the recommended PSI listed on the sidewalls of your tires. Typically this will be way too much. On average for a 33" tire, I would recommend that you run your tires at approximately 28-30 PSI. For a 35" tire, I would recommend running approximately 26-28 PSI. For a 37" tire, I would recommend approximately 24-26 PSI.


    Q: On the trail, how much should I air my tires down to?
    A: Typically, I recommend that people air the tires down to about 10~15 psi.


    Q: What are all the factory wheels that are available for the JK?
    A:Factory wheel type and sizes listed below:

    X Standard
    Painted Steel - Size 16 x 7.0

    X Optional
    Painted Cast-Aluminum - Size 16 x 7.0 (2007)
    Painted Cast-Aluminum - Size 17 x 7.5 (2008)

    Sahara Standard
    Painted Cast-Aluminum - Size 17 x 7.5

    Sahara Optional
    Painted Cast-Aluminum - Size 18 x 7.5

    Rubicon Standard
    Machined Cast-Aluminum - Size 17 x 7.5

    Backspacing on all factory wheels is 6.25"


    Q: What is the bolt pattern for a JK wheel?
    A:The bolt pattern on a JK is 5 x 5


    Q: Will a 33" tire fit on the factory spare tire mount without causing any warping or damage to the tailgate or mount?
    A: You should be just fine with a 33" spare tire especially if the sidewalls of it is making good contact with the rubber isolators on the tailgate. The isolators will help prevent the jiggling of the tire and that is ultimately what will cause you problems down the road.


    Q: What size are the lugs nuts used and what socket will I need to remove/install them?
    A: The lug nuts you will need are 1/2"-20RH and you will need a 3/4" or 19mm socket to remove/install them.


    Q: How many foot pounds should I tighten my lug nuts to?
    A: You should tighten your lug nuts to 95 ft. lbs. of torque.


    Q: Is there any advantages to running a larger rim size vs. a smaller size?
    A: Yes, a larger rim size will reduce tire sidewall flexing and this will provide better handling on pavement. On the trail, less sidewall flex can also help to make your Jeep feel more stable on off camber situations.


    Q: Are all rims the same or is there a certain type of rim for offroading?
    A: So long as you can mount your tire on it, a rim is pretty much a rim. Some Jeepers prefer to run steel wheels as they are typically much more affordable, are easy to touch up and will bend as oppsed to breaking but, they also tend to be heavier than aluminum. The one thing I would recommend is that you try and get a rim that is about 8" in width. The narrower width will help keep your tires from loosing a bead when aired down for the trail.


    Q: How do you determine what size tire will fit what size rim correctly?
    A: Typically, most off road tires come in a 12.50" width and for the most part, a 10" wide rim is what you would want. However, unless you are running beadlocks, I would recommend that you select a wheel that is 8" in width or there abouts. When aired down for the trail, the narrower width will help prevent your tires from loosing a bead.
    Last edited by wayoflife; 03-22-2012 at 08:17 AM.

  4. #4
    JK-Forum Founder
    Join Date
    Jul 2006
    Location
    Laguna Niguel, CA
    Posts
    36,535

    Default Axles, Gears & Drivetrain

    AXLES, GEARS & DRIVETRAIN

    Q: How can I correct my speedo for bigger tires?
    A: Your dealership can calibrate your JK's speedometer up to a 32" tire. If you have larger than 32" tires, I have successfully used a Pro Comp ACCU Pro to calibrate my JK's speedometer to accurately read the 35" tires and 5.13 gears that I am currently running. Click on the link below to see my write-up for this:

    https://www.jk-forum.com/forums/modified-jk-tech-2/lets-talk-speedo-correction-17051/


    Q: What gear ratio should I be running with 35" tires?
    A: In order to bring your Jeep's performance back to stock, you will need to run 4.88 gears with 35" tires. However, if you are looking for a little extra power, you should consider getting 5.13's. This is especially desirable if you have an automatic transmission.


    Q: What gear ratio should I be running with 37" Tires?
    A: In order to bring your Jeep's performance back to stock, you will need to run 5.13 gears with 37" tires.


    Q: Do I need new gears for both my axles or do I just need to regear the rear axle?
    A: On a 4WD vehicle, you will need to regear both axles.


    Q: I just had my axles regeared, is there a break in period that I should be aware about?
    A: Yes. After regearing your Jeep, you should try to go real easy on the gas and drive your jeep unloaded for about 15 to 20 miles. Stop and let your gears cool completely and then, try to drive nice and easy for about the next 250-500 miles. Change out your gear oil.


    Q: I just had my axles regeard and now they are whining. Is this normal?
    A: A little gear whine is normal during the break in period but after that, it should be pretty quiet. If it is not, there is a good chance that your gears may not be setup correctly and you should take your Jeep back to the shop that installed it for an inspection.


    Q: Are new driveshafts needed after installing a lift?
    A: You really should consider installing a new rear double cardin U-joint style drive shaft if you have lifted your Jeep JK Wrangler 3" or more and have a 2-door. This is needed because the short rear drive shaft of the 2-doors will be at a steep enough angle that the CV boots will wear out prematurely. However, in order to do this, you will need to buy a set of rear adjustable upper control arms so that you can properly set your pinion angle. 4-Door Unlimited models do not have this problem as their rear drive shafts are very long and a lift will not effect the angle of it too much. As far as the front goes, if you have an automatic transmission, you will need to replace the drive shaft with a double cardin U-joint style unit as well as the diameter of aftermarket shafts will be considerably narrower and will not come into contact with the transmission and/or skid plate. Failure to do this will result in the tearing of the factory drive shaft boot as it makes contact with the transmission. Manual transmissions will not have this problem and keeping the factory front drive shaft will not be a problem.

    NOTE: On a 2012-Up, you will want to install a new front drive shaft regardless if you have an automatic or manual transmission. Assuming you install new, longer shocks with your lift, the extra droop you will see at a flex will cause the slip shaft boot on the drive shaft to tear. However, that is just one problem you will encounter. Even if you install exhaust spacers or relocate the cross over, the CV boot at the output shaft will be sitting at a significant state of pinch and this will cause it to fail prematurely.


    Q: I want to run larger tires and want to know what is the bare minimum I should do to beef up my front axle?
    A: If you plan on running 35" tires or larger, you really should consider having a set of axle C gussetts installed. These will help prevent the axle C's from bending which is a common problem and one that will result in unwanted camber in your wheels. This is the bare minimum you should do.


    Q: I want to run larger tires and want to know if axle tube sleeves are something I will need?
    A: No. While they are nice to have, axle tube seals are far from needed even if you are running significantly larger tires than stock. Yes, there have been a very small number of reported axle tube breaks since the JK was first put into production but, evidence has shown that these breaks were the result of faulty manufacturing and tire size had absolutely no bearing on them. The most common form of axle tube failure comes in the form of bending but, reports of this is very uncommon and, even if your axle were to bend, it would not prevent you from driving your JK. If budget is an issue, I would recommend saving your money and buying a set of chromoly axle shafts instead.


    Q: I just installed larger tires on my Jeep - do I need to upgrage my axle shafts?
    A: Installing a set of rear chromoly axle shafts is not needed. The factory rear Dana 44 shafts have proven themselves to be quite strong and hearing about them failing even with 37" tires is very rare. If you plan on running 35" tires or larger, installing a set of front chromoly axle shafts is definitely a good idea especially if you have an X, Sport or Sahara model JK as they only have a Dana 30 front axle. In addition to being considerably stronger, chromoly axle shafts typically come with full circle clips and this will help prevent your U-joints from coming apart and failing.


    Q: What is the most common reason for front axle breaks?
    A: Factory front axle shafts have U-joints that are held in place with C-clips. Over time and a lot of wheeling, theses C-clips will work themselves free and this ultimately allows the U-joint to fail. In addition to being considerably stronger, chromoly axle shafts typically come with full circle clips and this will help prevent your U-joints from coming apart and failing.


    Q: Are CV style front axle shafts really that much better than U-joint shafts?
    A: CV style front axle shafts are very stong and will not fail the way factory shafts with standard C-clips do. However, aftermarket chromoly shafts come with full circle clips and will not fail the way factory shafts do either and, they are typically a lot more affordable.


    Q: Is there a good chart that I can refference to help me determine what gear ratio I should have installed based on the tire size I am running and the RPM's that I hope to be running?
    A: Thanks to the help of the member Jpop, the chart below should be of assistance to you:



    Last edited by wayoflife; 05-16-2012 at 07:52 AM.

  5. #5
    JK-Forum Founder
    Join Date
    Jul 2006
    Location
    Laguna Niguel, CA
    Posts
    36,535

    Default Bumper & Armor

    BUMPER & ARMOR

    Q: Will an aftermarket heavy duty front bumper cause my Jeep's air bags not to work anymore?
    A: No, the accelerometer sensors that trigger your air bags are located in the center of your Jeep and NOT in your front bumper. Installing an aftermarket heavy duty front bumper will not prevent your air bags from deploying.

    Q: What are crush cans and are they needed to activate my air bags?
    A: Crush cans are quite literally two cylindrical shaped protrusion extending from the steel sub-structure of the front bumper that look like cans. These are designed to "crush" and absorb low speed impacts. There are NO electronic devices or sensors attached to or located within these cans and an absence of them will not prevent your air bags from deploying.

    Q: What aftermarket bumpers are available for my Jeep JK?
    A: Front Bumper Comparison

    Q: Does the Jeep JK Wrangler come with skid plates?
    A: Yes. Unlike Jeeps in the past, the new Jeep JK Wrangler comes equipped with substantial underside armor designed to protect the transmission, transfer case and gas tank.

    Q: How adequate are the skid plates that come on the Jeep JK Wranglers from the factory?
    A: The skid plates that come on the Jeep JK Wranglers from the factory are designed well and can take a significant amount of punishment without failing.

    Q: Are aftermarket skid plates necessary?
    A: NO. Unlike older Jeeps that did not come with any underbody protection, the new Jeep JK Wrangler does come equipped with substantial armor designed to protect your transmission, transfer case and gas tank. I would however recommend that you do add protection for the one thing that didn't come armored up from the factory and that would be your oil pan. A simple skid like Rancho makes or a heavy duty replacement pan like Benchmark Designs makes would offer more than adequate protection.

    Q: Is it necessary to relocate the EVAP canister or install a skid to protect it?
    A: No, it is not necessary but depending on how much lift you have and the kind of terrain you play on, there is a high likelyhood that you may knock it off. If your EVAP canister gets knocked off, your ability to drive your Jeep will not be effected and more times than not, you can simply reinstall it on it's mount and be on your way. Relocating or armoring up your EVAP canister will just help prevent any damage to it.
    Last edited by wayoflife; 04-11-2010 at 02:31 PM.

  6. #6
    JK-Forum Founder
    Join Date
    Jul 2006
    Location
    Laguna Niguel, CA
    Posts
    36,535

    Default Body Modifications

    BODY MODIFICATIONS

    Q: What is a 'BL' or body lift?
    A: A BL or body lift is a series of small round pucks made out of aluminum or polyurethane, are typically 1" tall and are designed to stacked on top of your factory rubber mounts separating the tub or body of your Jeep from the frame. Installing a body lift is the cheapest way to gain an additional inch of fender clearance and will allow you to install slightly bigger tires but it will not change or improve the characteristics of your suspension at all.


    Q: What size tire will fit on the factory spare tire mount?
    A: A 33" tire will fit fine as well as some 35" tires just barely but your bigger problem will be in regards to your wheels and the amount of back spacing they have. Factory BS is 6.25" and if you get something that has too little BS, you may find that your tire side walls will no longer make contact with the rubber isolators and this can be a problem. Without the side walls making contact with the isolators, the spare can jiggle around enough to cause your tire mount to break. At least, this was a common problem on the TJ's.

  7. #7
    JK-Forum Founder
    Join Date
    Jul 2006
    Location
    Laguna Niguel, CA
    Posts
    36,535

    Default Troubleshooting

    TROUBLESHOOTING

    Q: What is 'death wobble'?
    A: Not to be confused with a really 'bad shimmy' in the steering wheel, death wobble is a violent, uncontrollable shaking of your entire Jeep that typically can only be brought under control by bringing your Jeep to a stop. Typically, death wobble can be triggered after hitting a bump in the road or going over rough surfaces like rail road tracks.


    Q: What are common causes of 'death wobble'?
    A: While loose suspension or steering components, bad ball joints, a toe-in setting that is off or even unbalanced tires can 'instigate' death wobble, it has been my experience that death wobble can ONLY occur if you have a problem with your front track bar. Specifically, track bar bolts that are not properly tightend to the appropriate toque setting will allow death wobble to occur as would worn out track bar bushings, track bar mounting holes that have been wollowed out or track bar mounts that are fatigued and/or are failing. Essentially, anything that would allow your front track bar to shift around or move can and will cause death wobble. A steering stabilizer that is bad WILL NOT cause death wobble nor would the installation of a heavy duty unit fix it.


    Q: My Jeep feels flighty at highway speeds and tends to wander a lot, do I need a new steering stabilizer?
    A: NO - IF you have your suspension/steering dial in correctly, a steering stabilizer isn't really needed at all. While one might act as a bandaid and help to hide or mask wandering or flighty steering, a new steering stabilizer WILL NOT FIX ANYTHING. For improved handling at highway speeds, you will need to add more positive caster and the best way to do this is with a set of adjustable front lower control arms.


    Q: I just installed a 3"+ lift and now my ESP keeps going off. What do I need to do to address this?
    A: Make sure that your steering wheel is perfectly centered and if you have adjustable front control arms, make sure to set your castor angle to compensate for your new lift and larger tires.


    Q: I just went wheeling and now my steering wheel is no longer centered. What could have happend?
    A: More than likely, you have bent a steering or suspension component like your drag link, tie-rod, track bar, or even lower control arm. Check everything carefully for impact scars as that will help you to identify what was damaged. Another possibility is that your steering box has a bent pitman arm shaft. This is something that has happend to me before.


    Q: How do I recenter my steering wheel?
    A: To re-center your steering wheel, use a 15mm wrench to loosen the 2 nuts on the turnbuckle on your drag link as shown in the pic below. Then, rotate the turnbuckle clockwise or counter clockwise as needed while a friend watches the steering wheel (or you periodically check on it yourself) go back to center. Once re-centered, secure the nuts and take it for a drive to check your steering wheel. This may take a few tries to get it on 100% but that’s all there is to it.




    Q: I get a shaking or a shimmy in my steering wheel at a specific speed or speed range? What could be causing it?
    A: Typically, a speed sensitive shaking or shimming in the steering wheel is caused by tires that are out of balance.


    Q: I just went wheeling and now my Jeep rides rough and/or I have a bad shaking of the steering wheel. What could it be?
    A: If you were playing on the rocks, it is possible you threw a wheel weight. If you went mudding, you most likely have mud caked on the insides of your wheels and this is throwing off your wheel balance.


    Q: I just installed a lift and my rear sway bar links rubbing the wheels and/or tires. What should I do?
    A: Install your sway bar links on the inside of your sway bar and axle mounts.


    Q: I just installed a 3"+ lift on my Jeep JK Wrangler with automatic transmission, went wheeling and now I here a 'click-click-click' sound coming from underneath. What could it be?
    A: More than likely, your front drive shaft boot has made contact with your automatic transmission skid plate and is now torn. Unfortuantely, the only fix for this is to replace your entire driveshaft as the boot is not serviceable. You should be fine with the tear for a while but I would recommend replacing your factory drive shaft with an aftermarket double cardin u-joint style unit as they will be considerably narrower in diameter and will not make contact with the skid plate.


    Q: Everytime I wash my Jeep, water keeps seaping out from the base of my mirrors. Is there a way I can fix this?
    A: Yes, you can drill a small hole at the base of the mirros to help it drain faster. Rubimon has done a write-up of this and it can be found here:

    https://www.jk-forum.com/forums/jk-write-ups-39/drilled-side-view-mirrors-1291/

    Q: I just installed a 3"+ lift on my Jeep JK Wrangler with automatic transmission and have torn the boot on my front drive shaft. What should I do?
    A: Unfortunately, if you have an automatic transmission, you will need to replace the drive shaft with a double cardin U-joint style unit. The diameter of the factory front drive shaft is too wide and the boot will come into contact with the transmission when flexing. Aftermarket drive shafts will be considerably narrower than factory and will not come into contact with the transmission and/or skid plate.
    Last edited by wayoflife; 12-15-2009 at 11:03 AM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •