Modifying your 4x4

The time has come and you have decided to modify your 4x4.
You have read the basics for gearing and now want to make some changes, but where to start?
That is a tough question and for every builder there is a different answer so we’ll go through some basics to help with the choices out there.
One thing to keep in mind is when you modify your suspension your 4x4 WILL handle differently, accelerate and stop differently. The best advice here is to go easy till you learn how your rig will react with different driver inputs.

Lift kits

There are 3 ways to lift your truck and most builders will use one or a combination of all to achieve the clearance or look they want to attain.
The lifts available are suspension, body and a “virtual lift” 

Suspension lifts
The suspension is the most common place to start and can vary between vehicle makes. These kits will contain everything from springs, drop bracket components, shocks, as well as optional extras but some of these options are a necessary part of the lift. Many will also have “upgrades” available, better shocks, skid plates and other visual improvements. 

Body lifts
Just as the name implies these kits lift the body off the frame for a few extra inches of clearance. Most kits available are in the 1”-3” range. There are those that will build their own but kits over 3” are not recommended for safety reasons as the leverage on these mounts in the case of a crash will cause the body to shift. Not all vehicles have these kits available for them so if your 4x4 of choice is a Jeep Cherokee or Grand Cherokee you will have a hard time finding a kit as these 4x4’s use a unit body construction so the body becomes the frame.

Virtual lifts
This is a bit of a loose term used when the body is cut for tire clearance. Many builder will trim fenders for the tires to have room to cycle through the uppermost travel so no travel is lost by low bump stops or creating a higher center of gravity. What will these do for me? Each of these lift methods has a different affect on the rig it’s used on. 

A suspension lift should increase ride height and frame ground clearance, in doing that this creates room for larger tires which in turn increases total ground clearance under the frame and under the axles. In most cases a suspension kit will increase the amount of available wheel travel; the exception here is many of the new trucks IFS front suspensions. Without custom parts the travel is limited to the suspension design. A body lift is just as it sounds; it lifts the body off the frame. By doing this it creates more TIRE CLEARANCE. It does get the body up a little higher away from potential damage but the frame and axles will make the first contact with a trail obstacle. The larger tires that can be fitted after a body lift will be the only part of this that will increase ground clearance. A virtual lift for the most part is used with one of the previous lifts to create room for the larger tires to cycle without making body contact and causing damage to the truck or the tires.

What do I want/need?

This is where you have to consider how you are going to use your 4x4.  There are legal requirements you have to meet as well as considering the overall strength of your running gear. If you are building something for show only this is not as critical. Some of the lift kits have “optional” parts that should not be considered optional. When it comes to your steering and brakes DON’T skimp here, it’s you, your passengers and the rest of the motoring public’s safety at risk here.  Steering corrections should not be considered options. Look into your options be it a drop pitman arm to the possibility of a cross-over or complete high steer system available to many models of 4x4’s from many different vendors.

The next over used item is shocks; more is most often not better. Choosing a shock that is properly valved for your application will net a far better ride or buy shocks that are adjustable. If quad shocks are an option they will likely be valved by the manufacturer to be run in pairs.

Now is when you must consider the strength of the stock components of your truck and if they will withstand the stresses of larger tires. Unless you are building a one ton truck with the heavy running gear already in it a light duty axle like those used in a Jeep you will not be very happy when those awesome 38” tires start breaking everything under your truck. All builds evolve as time goes on so if you want big off the start, look into an axle swap. Something that is often overlooked until it’s too late is brakes. With light duty axles the brakes are designed to stop small stock tires. As the tires get bigger they exert more leverage on parts and the higher rolling mass take longer and more power to stop.
In the aftermarket there are upgrades available to strengthen your stock pieces, parts from brake upgrades, alloy axles stronger u-joints, these can all increase the resistance to breakage but all parts have a limit.

Finally

Each build is different due to the owner’s tastes and needs, do your research and talk to your friends. If you see a nice truck talk to the owner, almost all builders will be more than willing to talk about their rig, what they have done and any problems they have encountered. Just because you have a lift and tires already done does not mean you are done, as you spend time in the drivers seat and out on the trail, your skills will improve and your desire for more challenging trails. As your skills increase your build will likely go through some changes. You will be making improvements or maybe something as simple as some tweaks or add-ons to the current set up.

Next month I will get into wheel travel and RTI indexes, what it means to trail performance.
As well as the choices available to you for tires, bias-ply, radials, tread designs and what should you consider for where you like to drive…………

    

Written by JBZukin