Performance Improvement Ideas

The Jeep Cherokee is an extremely versatile vehicle.  It is capable of comfortable highway driving, carrying large amounts of cargo and handles well in a variety of conditions.  

The true Jeep heritage of the vehicle becomes apparent when it is driven off road.  The solid axle suspension with coils springs in the front and leaf springs in the rear makes for an amazingly stable yet flexible platform even in its stock configuration.  

A couple of simply modifications to the stock setup can greatly improve the of road capability and can be carried out with simple hand tools and basic mechanical skill.  The first modification is to remove the rear sway bar.  This bar is not needed in most driving conditions and limits the articulation of the rear axle.  Simply remove the bolts holding the brackets to the bottom of the Cherokee and remove the ends of the bar from the axle.  

The second modification is to disconnect the front sway bar.  This bar is needed for highway driving but off road it limits the flexibility of the suspension.  Simply unbolt the bar from the brackets at the front axle and remove the connecting link.  Use an elastic cord to tie the bar up out of the way while off road.  The bar can be easily reconnected once you return to pavement.  

For most off road use, the low range setting of the transfer case is the best one to use.  Select low range by raising the lever all the way up.  Shifting the transfer case is often easier if the Jeep is rolling slightly.  The manual recommends a speed of 3 MPH.  The transfer case should not be shifted to low range at high speed due to the potential for damage due to over speed on the bearings.  When sitting still, sometimes the gears are hard to mesh.  A slow roll is best.  

Reducing the air pressure in you tires will greatly aid in off road traction.  There is a limit as to how low you can go however.  As you reduce air pressure, you will reduce the clearance under the axle.  Also, if you go too low the will not be sufficient clamping force to hold the tire beads to the rim.  In the case of a side load from a rock, the tire can be pushed off the rim resulting in a sudden deflation.  For stock tires something in the 15 to 20 psi range is a good starting point.  Adjust to your terrain and driving style.

When approaching an obstacle, the first step is to carefully observe the driving line.  Often this is best done by exiting the vehicle and walking the trail.  Be sure you know where you will go after crossing an obstacle as well.   

When crossing rocks that are taller than the clearance under your axles, carefully place one of your front tires on the rock allowing your Jeep to climb over the rock.  As you go over the rock control your speed so that you descend slowly as your front wheel drops off the rock.  Rocker panel protection is nice to have here as the rock may impact the pinch seam under the Jeep as you go down.  Go slowly to minimize the impact.  Move forward smoothly and allow your rear tire to walk over the rock as well.

With its leaf spring suspension, the rear of the Cherokee is slightly stiffer than the front.  However due to the engine placement it is also lighter weight.  Pay attention to where the rock is in relation to the rear tire.  When the rock is six to eight inches away from the rear tire, accelerate slightly to build momentum to carry the Jeep up and over the rock.  With practice this maneuver can be done smoothly and allow you to traverse larger obstacles with ease.  

When making a very steep climb of a rock ledge or other similar obstacle look for ways to use the momentum of the Jeep to help you get over the obstacle.  For example, if the rise on the right side of the vehicle is too tall to get over but you can use something on the left side as a ramp, go higher than you would need to and then turn the front of your Jeep down hill to build some momentum to get the rear of the truck over the obstacle.

  In the event of a loss of traction on one front wheel, try turning the steering back and forth from one extreme to the other to see if there is any place it will grip.  Develop a feel for when your Jeep is getting traction and be prepared to move in whatever direction the traction will take you.  

When climbing, develop and maintain momentum.  Do not drive so fast as to bounce over humps or you will loose traction.  However, keep enough speed to move you past points of lesser traction.  

In mud momentum is critical.  Try to build speed before entering a muddy spot.  Be prepared for the drag on the axles and underbody to slow your speed.  Never enter water without checking the depth first.   

The Cherokee has the alternator located very low of the passenger side of the engine.  Try to keep this side of the vehicle out of mud puddles as much as possible.  Mud will quickly kill the Jeep alternator.  

The air intake of the stock Jeep is just above the bumper.  If you enter deep water too fast, a wave of water will build up and be sucked into the air intake potentially stalling or even damaging the engine.  One way to increase the fording depth is to disconnect the air intake hose from the air box and rotate it to the rear of the engine compartment.  If the hood seals are good, an air pocket forms near the firewall when going into deep water.  By pulling air form this point you can safely cross deeper water than by pulling air form the normal location.  Be sure to return the air hose to the filter box after crossing the water to prevent dust form being pulled into the engine.  

If you should become stuck on any obstacle, first try backing out the way you came in.  Often by simply backing up and entering an obstacle with slightly more momentum, you can cross it.  If you are unable to back up try turning the wheels from right to left to see if there is any position where they might get traction.  Use whatever traction you can find to move your Jeep to a different position.  

If you are stuck in mud or other loose surface, try rocking the vehicle back and forth to see if you can free it.  If you can develop a rhythm of moving back and forth, you may be able to generate enough momentum to get out of the hole you are stuck in.  

You can also try putting rocks or sticks under the tires to help bring your truck out of a hole.  It may be necessary to jack up the truck to get material under the tires.  

If all else fails, use a hand winch or jack to move the vehicle to another position.  Usually a move of a foot or two is all that is required to get you going again.

If a pull from another vehicle is needed. Use care when hooking up the recovery strap.  Avoid using straps with cast metal hooks.  These hooks can break and cause the strap to rebound and possibly cause damage or injury.  If you do not have proper tow hooks installed, you will need to connect to a secure portion of the Jeep.  In the rear, attach the trailer hitch if so equipped.  In there is no tow hook or trailer hitch, wrap the strap around the rear of the leaf spring.

In there are no tow hooks in the front, you will need to attach the strap directly to the front axle.  Either wrap the axle with the strap or connect to the sway bar brackets.  The stock bumper brackets are not strong enough to pull from without damaging the bumper.

Take up the slack in the strap carefully.  Coordinate the pull and only pull as far as needed for the stuck vehicle to regain traction.  In case of being extremely stuck, it may be necessary to bump the vehicle being pulled.  In this case get a small amount of slack in the tow strap and have the towing vehicle move forward briskly to build a small amount of momentum before beginning to pull.  Be very careful not to get too much slack as the sudden jerk can damage either or both vehicles.

As you learn to drive your Jeep Cherokee off road you will be amazed at what it will do.  Even a stock XJ can traverse obstacles that look impossible to drivers of other vehicles.  As your experience grows you will soon see the benefits of modifications like lockers, lifts and larger tires.  However, no amount of modifications will be a beneficial as practice behind the wheel.

Go off roading every chance you get.  Enjoy the outdoors with your Jeep Cherokee.

For more low cost suspension tricks see my Cheap Jeep page.