Tomken Machine has a 6" lift available, it's the tallest lift I'm aware of for XJ's.

My son has an 81 RHD CJ7 originally built for the Malaysian market. Currently it is running on the original Goodyear Tracker AT 9-15 tyres ( its only done about 6000 miles) on the original 15" rims. When offroad in the mud we run into problems with lack of traction and clearance (my M38-A1 on 7.00 16 SAT's outperforms it). We need a set of wheels and tyres which will be used solely offroad to overcome these problems. I can obtain new wheels in either 15 or 16 inch sizes with whatever offset is required. What is the largest tyre/wheel combination we can fit without a body lift and what offset will we need?  Gearing should not be an issue as with the low rev torque of the diesel we have not needed low ratio 1st yet."

You can run up to a 31" tall tire. To find the diameter of a metric tire in inches, go to http://www.dirtroad.com/gears.htm. If you decide to purchase new rims, retain the same backspacing as the original rims.

Contact JB Conversions and Mountain Off Road Enterprises (M.O.R.E.) at 970-625-0500. Both have 1" TJ body lifts.

In my opinion, there's nothing wrong with removing the trackbar on a YJ. None of the older CJ's were equipped with one, and I can only assume that Chrysler added the track bar to the YJ to minimally improve on road handling. It would not surprise me if you didn't notice any difference in handling with or without the track bar installed. The track bar only serves to keep the rear axle from shifting side to side during normal on road driving. On older CJ's, this lateral movement was controlled by the "fixed" mount of the leaf springs. As long as the leaf spring bushings were in good shape and stock length shackles were used, little if any lateral movement of the axle was allowed. Off-road, the track bar performs the opposite function.  As the axle moves up or down, the track bar forces the axle to one side or the other (depending on whether the springs are being compressed or released) which will create a bind since the leaf springs also control lateral movement. Obviously, this will greatly inhibit wheel travel. MIT did you a favor by not reinstalling the track bar.

An experienced mechanic should be able to complete the job before lunch. Place the Jeep on jackstands located underneath the framerails in order to remove the vehicle weight from the springs. Support the axle with a floor jack and remove the springs from the frame (there's no need to remove the U-bolts). Lowering the axle, with the springs attached will allow enough room to gain access to the bushings.

A 265/70/R15 tire and a 30x9.50R15 tire are virtually the same size. The height of either tire should be fine, but the width may cause a slight rub on the lower control arms in a sharp turn. To determine your speedometer error, check out (gears.htm).

Check the driver's side door jam for a sticker that will indicate your VIN#, GVWR, and stock tire size among other things.

A 3" body lift would allow plenty of room for 32" tires. You will need new rims at least 8" wide with less backspacing than stock to avoid tire contact with the leaf springs.

Rubicon Express www.rubiconexpress.com and Tomken Machine www.tomken.com both offer suspension lifts for XJ's that will clear 33's.

I don't see any problem with using steel at all.

It's true that ground to axle clearance will not increase with a suspension lift alone, but frame to ground clearance will increase. You'll appreciate this when cresting a steep hill or driving over a large rock. With the right suspension lift, both wheel travel and ride could be improved. The Rancho 2.5" kit offers a surprisingly smooth ride (in my opinion, better than stock). I suspect the Old Man Emu kit is just as good, if not better. In your case, I don't think you need to "beat up" your Jeep off road to realize the benefits of a suspension lift. If nothing else, you'll keep the 31's from rearranging your fenders.

Late model Jeeps with 4 cylinder engines were almost always equipped with 4.10 gears. The easiest way to verify this is to check the axle ID tag attached to the differential cover, "4.10" should be clearly stamped in the tag. If the tags have been removed, you can always count driveshaft revolutions per tire revolution. A little over 4 turns of the driveshaft per turn of the wheel would indicate a 4.10 ratio. The factory axles should have been a Dana 35 rear and 30 front.

Considering the moderate tire size that you're considering combined with the already low axle ratio, I really wouldn't consider a swap to lower gears as mandatory. You won't do any damage to your Jeep if you don't change gear sets. Performance will diminish somewhat with the 4.10's, swapping in a set of 4.56's would be ideal with the new tires. Whether the difference is worth a grand of gearsets is up to you.

As you already know, many of the popular tire sizes for 4x4 use are not the same size as stated on the sidewall. With that said, a 30x9.50R15 will work well on your Cherokee with the Up Country suspension package. The 30" tire is normally a quarter to a half inch shorter than advertised. A 31" tire will be too large. My experience is that retaining the factory backspacing and rim width on Cherokee's allows for better clearance than an aftermarket rim with less backspacing would. With the stock backspacing, the 30" tires will tuck neatly underneath the fenders when off road (especially in the rear), whereas a rim with less backspacing would push the tire farther out creating contact with the fenders and much less potential wheel travel.

A well designed 2" suspension lift will not cause vibration in a Wrangler. I'd wager that the operating angles for each U-joint on the rear driveshaft are not equal. This condition is an all too common cause of driveshaft vibration in 4x4's with suspension lifts. Check out the "All about U-Joints" article (http://www.dirtroad.com/articleb.htm) for the cure.

Yes.

If your Cherokee does have the "off-road" or "Up Country" packages, then it should have skidplates for the transfer case and fuel tank, and usually two tow hooks underneath the front bumper. The Up Country package also included better shocks, and slightly taller springs for a l" lift.

A 31" tire would be the absolute max on a stock Cherokee, 30" tires are probably a better choice to avoid any interference.

To my knowledge, the differences between the old 4.0 and the newer high output version included a minor change in the cylinder head for improved airflow, elimination of the old cast iron exhaust manifold in favor of a tubular "header", and a new engine computer. Mopar sells a new computer for your old 4.0L that claims an instant increase of 10 hp if you're interested.

Since you obviously have no problem with a little custom fabrication, use YJ springs instead of CJ springs. The ride will be much softer, with a corresponding increase in articulation. I've been very impressed with Old Man Emu suspension systems, and have no hesitation in recommending their springs.

To calculate your top speed, check out www.dirtroad.com/gears.htm

Yes.

A suspension lift is obviously beneficial for off-roading, but certainly isn't mandatory. The max tire size for a stock YJ is a 30x9.50R15. On the stock wheels, these tires will rub the rear of the leaf springs in a sharp turn. When you shop for new rims, be sure to use wheels with less backspacing to cure the problem.

Short of recommending any specific manufacturer, just remember that the old saying "you get what you pay for" applies to suspension lifts as well. Talk with several shops before deciding on a kit.

A 12.5" tire will bulge quite a bit on an 8" rim, but I've been very happy with the setup. That sidewall bulge will protect your expensive rims from damage. I'd recommend running a fairly low tire pressure for even tread wear with this setup. Something in the neighborhood of 15-20 psi in the rear and around 25 psi in front.

The problem you describe is very indicative of improper driveshaft angles or a worn out U-joint. Check out http://www.dirtroad.com/articleb.htm for the fix.

You should consider longer brake lines if you intend to spend much time off road in your CJ. A dropped steering arm won't be necessary for the minimal lift your considering. Most kits come with 4 new springs, but some manufacturers don't supply new spring bushings with the kit. If you're U-bolts are rusty or banged up, you'll need to replace them, they're almost never included in the kit. Be sure to get longer shocks to go with the lift.

OME has a 3.5" YJ kit that will clear 33" tires. For 35" tires, you'll need to add a 2" body lift. A 12.5" wide tire is as wide as you should go on an 8.5" rim.

If you intend to ever take your Jeep off road, you'll need longer brake lines.

The easy way to determine axle ratio's is to check the ID tag that's bolted to the front differential cover. Look for a number such as "3.08" or "3.55". If the tag is missing, or you have reason to believe the gears have been swapped before, you'll have to jack up the rear of the vehicle and count driveshaft revolutions. With the transmission in neutral, rotate the driveshaft by hand and count the number of driveshaft revolutions for one revolution of the tire. Three and a half driveshaft revolutions for one tire revolution would mean a 3.55 ratio. Regardless of what gears you currently have, whether they are "good enough" for 33's is up to you. The loss in performance will be significant with the larger tires, but whether the performance drops enough to necessitate a gear swap is your call.

I'd like your opinion on what lift(s) I should seriously consider for this. I'm on a limited budget and would like to do this as economically as possible (don't we all). I'd also like info on what I'll have to buy in addition to the kit itself (ie dropped pitman arm, brake lines, etc...). All the info you can give me will be greatly appreciated! Thanks!!"

Old Man Emu Suspensions has a 4" lift for YJ's that is easily adaptable to your CJ. The rear springs are a direct swap, the front YJ springs are wider than the CJ springs, but can be installed easily with a bolt on kit from JKS. This kit should provide a much better ride than a comparable 4" CJ kit, look for an upcoming installation and test at Dirt Road soon.

You already have a good idea of the corrective measures that need to be taken when moving the axles farther away from the frame. You will need a dropped steering arm, longer brake lines and spend a little time shimming the rear end for proper driveshaft angles.

Teraflex (www.teraflx.com) has a nice lift for your Grand Cherokee that will clear 31's perfectly. What wheels and tires you decide to use are really a matter of personal preference for your off road needs. I will admit I'm partial to the BFGoodrich AT or MT tires, they simply haven't let me down yet.

I was thinking about getting 2" Softride springs and Rancho RS 9000 shocks. I know the RS 9000 are pretty reliable but what about the Softride springs? can they take a beating?"

Look into the Old Man Emu line of suspension lifts and matching shocks from ARB. They will provide an excellent ride, plenty of travel, and take a beating.

Yes, the Cherokee suspension lift also fits the Comanche.

Your Wrangler with round headlights is a TJ. You will need 3-4" suspension lift to accomodate 33" tires. Check out Teraflex (www.teraflx.com), they produce a very nice suspension system for your TJ. The Dana 44 is a heavier duty rear axle option over the stock Dana 35 and has nothing to do with tire clearance.

The 31x10.50's rub because of the stock rim's backspacing. An aftermarket rim with less backspacing should cure the rub. If you want to keep the stock wheels, stick with 30x9.50's.

The stock suspension does not meet the needs of the local terrain. I live in Whistler, BC, which has lots of logging roads and rough areas that need ground clearance. With my current suspension I keep bottoming out on cross streams and creeks. I also use the highway to get to and from places and would like to still maintain a smooth ride. Any suggestions would be helpful as I would like to try and do as much myself as possible. It is a great hobby!!!!!!! Thank you"

Look into the Old Man Emu suspensions for your YJ, they are a little more expensive, but they are of extremely high quality. They should deliver a good ride on the streets too. With a good floor jack/jack stands and some common hand tools, you should be able to hand the installation in your own driveway.

You could install 31's with only 1-1/2 inches of lift, but the tires will be close. You'll probably experience some rub in twisty off road situations. A 2-1/2" lift would be preferable with 31's for maximum articulation and travel without rub.

The rear end would sit noticeably low. Keep in mind that a shackle 1" longer than stock will only gain 1/2" of lift. You would need a shackle 3" longer than stock to make it sit level! A shackle that long would be dangerous and destroy the rear driveshaft angles causing vibration and probably driveshaft failure.

The only good thing about an add-a-leaf lift on a YJ is that it's cheap. The problem is the ride quality after the leaf is installed. The heavily arched leaf will make the spring pack way too stiff for not only a comfortable ride, but for good articulation off-road. The change in the axle centerline will be very slight and won't be a problem. The change in pinion angle from the lift will give you grief though, you'll need to lower the transfer case and install shims between the spring pack and axles to retain proper driveshaft geometry and avoid vibration, don't forget longer shocks too.

You shouldn't have driveshaft vibration problems if you purchase a complete kit. Problems tend to arise when less expensive add-a-leaf type or even shackle lifts are used, neither of which take driveshaft angles into account. You'll have to make a trade off regarding the wheel backspacing. The stock backspacing would keep the majority of your 33x12.50's under the fenders, but would greatly decrease your turning radius due to the rub of the tire against the leaf spring. To solve the rub, you have to decrease backspacing, in doing so you push the tire farther out of the fenderwell. My advice is to try several different combinations at the tire store and pick the compromise you can most easily live with.

The 30's are a tight fit as it is on a stock XJ. Don't install 31's without a suspension lift.

Don't attempt to install the 31's on your YJ without some sort of lift. The lack of clearance would be both dangerous and damaging to your Jeep. After the lift, fender rub won't be the problem. The problem is the 31's on stock rims will rub the front leaf springs in a sharp turn, enough that it will significantly reduce your turning radius. Measuring the backspacing of your stock rims and subtracting about an inch should put you in the ballpark to avoid tire rub.

Yes, but that's the max size without a lift.

Not at all, virtually every major aftermarket suspension manufacturer has a suspension lift for your Cherokee. Most of the kits only require replacing the springs and shocks.

Body lifts and suspension lifts are very similar in that the greater the lift, the more corrections have to be made. The only problem I can see with your minimal body lift is the need to relocate the fan shroud and radiator down an inch after the body lift is installed.

You've heard the cliche "you get what you pay for"? I've found the ARB/Old Man Emu suspensions perform very well. If you don't want to sport for the OME suspension, the Rancho 2.5" kit is pretty good.

A 2" suspension lift on a YJ is right on the border as far as lowering the transfer case. You'll will need to use shims between the axle housing and springs to rotate the pinion upward, and that alone may be enough to avoid driveshaft vibration. If not, you'll need to either lower the case or swap to a CV style rear driveshaft.

The stock rims are 6" wide and are a little narrow for a 30x9.50 tire. The 30" tires on the stock rims will also rub the rear portion of the leaf spring during a sharp turn. The wider rim will lessen the problem, but may not cure it, it depends on the offset of the new rims. No suspension or steering modifications are required to run the 30" tires. I like BFGoodrich all terrains for the daily driven 4x4. They're fairly quiet on pavement and will have much better traction off road than the stock tires. They make chains for a 30" tire, but I'm afraid there won't be enough clearance and they will probably hit your fender flares. You just might find you don't need the chains with the new tires anyway.

A 30" tire is the max for a stock XJ. There are no body lifts for your Cherokee because it is a unibody vehicle. The frame and body are integral, meaning you can't stick spacers in between the two to achieve lift.

It depends on the offset and width of your existing rims. On the stock rims, a 30x9.50R15 is about as wide as you can go. Be warned though, these tires will rub the leaf springs in a sharp turn with the stock rims. You can buy wider fender flares if you're concerned about coverage and still want a wider tire.

Fourth, and last, I want to add a receiver hitch to my Jeep. Mopar only offers a class I. That would probably be okay if I only wanted to tow trailers (because the max 2,000lbs is a saftey max for the Jeep itself). But because my Sahara came with front, but not rear tow hooks, I need something in the back to hook onto if (when) I get stuck front-end in. I also plan to hook a ski/bike carrier to the hitch. What do you recommend? I'd prefer something with bolts that matched the already existing holes in my frame."

I'll answer in the same order that you asked.

If you wanted to install a 2" taller tire, you could install a 1" lift and have the same vertical fender clearance. The problem is the suspension will still compress until it hits the bumpstops, meaning you've probably rearranged your fenders with the larger tires. You could solve the fender interference by lowering the bumpstops 1", but now you're taking away that much desirable suspension travel. Most suspension lifts (especially those for the TJ) offer much greater suspension travel than stock. To take full advantage of the travel, you have to run a tire that won't hit your fenders at full compression.

The Trac-Loc is not a true locker. It is a clutch-type limited slip unit. It's ability to transfer torque equally to both axle shafts is dependent on the friction of the clutches. As the unit wears, it's effectiveness drops dramatically.

There is no danger when properly using swaybar disconnects off-road in slow-driving situations. Disabling the swaybar simply allows better articulation on the axle. Never leave the swaybar disconnected during high speed use on or off road, the body roll without a swaybar and it's effects on steering are more than a handful.

You could either install the Mopar hitch or buy an aftermarket bumper from a company like Currie Ent. or Tomken Machine that has a built in hitch. Both companies also sell a tow hook that slips into your receiver if/when you do need to pull or be pulled from the rear.

Tomken Machine (www.tomken.com) at one point was working on a coil spring conversion, you might call them to see if they've finished development.

As long as your current rims are wide enough (15x10 at least), then you shouldn't have to make any changes.

I don't know whether the front coils are interchangeable between the ZJ and XJ. I do know that if your XJ wasn't equipped with the "Up Country" package than you could gain an inch of lift by swapping in a set of springs from another XJ with the package.

Teraflex (www.teraflx.com) recently introduced a very promising 3" lift for the ZJ's that clears 31's perfectly. The only 2" lifts I've seen consist of coil spring spacers. My advice would be to buy the highest quality kit with the height you want the first time, rather than ripping out the spring spacers a year later in favor of new springs. Don't worry, with time, your kids will get taller! The 15x7 rims will work fine with up to a 10.5" wide tire.

Changing your tire size does not affect your engine performance. Your 4 cyl. will be producing the same 120 horsepower regardless of tire size. The decrease in performance comes from the larger tires effect on the end drive ratio. Since a 33" tire covers a greater distance in a single revolution than the stock tire, the change in performance would be similar to installing higher axle gears (lower numerically). For instance, your 4 cyl./5 speed combination comes from the factory with 4.10 gears. Installing 33" tires would have the same overall effect on gearing as installing 3.35 axle gears (3.35 axle gears actually do not exist for your Jeep, but that's not the point). The formula is (original tire diameter/new tire diameter) X original axle ratio = effective axle ratio. To bring performance back to near stock, you'd need to install lower (higher numerically) axle gears to offset the increased tire size. To maintain the original overall gearing with 33" tires, you'd need axle gears of approximately 5.00:1. Since 4.56:1 gears are the lowest available for your axles, you will not be able to completely offset the increased tire size. The increased weight of the larger tires as well as decreased aerodynamics will also play a part in an overall loss of performance. Whether the resulting performance of your TJ is satisfactory is up to you. Even if you install the 4.56 gears with the 33" tires, I'd suspect a large portion of your highway driving will be in 4th gear instead of overdrive. A 31" tire (with 4.56 gears) is the largest tire you can run without a big decrease in performance, particularly on the highway.

You've got the right idea with the 2.5" suspension and 1" body lifts to run 33's. Your driveshaft U-joints will be happier with the moderate suspension lift and you're less likely to experience vibration problems. I don't think you'll have any problem with tire rub even if you don't cut the fenders/flares. There is also a good possibility that the 2.5" lift will deliver better articulation since the 4" springs tend to be grossly stiff.

There currently aren't any off the shelf "kits" for a Wagoneer spring over. You might try contacting 4x4 shops in your area to find one with experience performing the conversion.

The only thing that wouldn't apply is the problem of some of the Jeep's super short rear driveshafts. I don't know of anyone that makes a kit, but even if somebody did I'd still suggest it would be best to have a professional shop with several successful spring overs under their belt perform the conversion.

You'll probably have to use a rim with slightly less backspacing so that the larger tires will not rub the leafs in a sharp turn. Try and retain as much backspacing as possible without tire rub, this my require a little trial and error while you're at the tire store but when you're spending that much money, they're willing to work with you. For 31x10.50R15 tires, 15x8's would be a perfect match.

Your 215/75R15's are about 27" tall. With 30" tires your speedometer will read 70 mph when you're actually traveling about 77mph. This is just a close estimation because 215's aren't exactly 27 inches tall and 30's are actually a bit shorter. The formula is (new tire diameter/original tire diameter) x indicated speed = actual speed. You can correct the speedometer reading by either swapping to lower axle gears or by changing your speedometer gear. If you have a 5 speed with your 4 cylinder, then you have 4.10 axle gears. Since the larger tires have essentially the same effect as installing numerically lower axle gears, the 30" tires would feel like 3.69 axle gears with stock tires. Since 3.69 axle gears were never produced, you'll have to settle for the closest match, which is 3.73. Replacing your existing speedometer gear with one for a 3.73 geared TJ would correct the error caused by the tires. Replacing the speedometer gear however, doesn't do anything for the perceived power loss after adding larger tires. The much more expensive option of replacing axle gears with numerically higher gears will not only solve your speedometer error, it will also nearly eliminate any perceived power loss. Again assuming you have 4.10 gears, a swap to 4.56's would perfectly offset the increased tire size. Of course, you could always just mount the new tires, know your speedometer is going to read about 10% slow, and downshift a little more often up big hills.

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