Before you get started off-road, would be best to know what parts are actively used and abused during your time off-road. Understanding what components are at work and their specific functions will help you later on down the road when making decisions pertaining to your setup and also troubleshooting. So we’re going to cover the components and basics of an off-road setup.
Coil springs are becoming more common in off-road setups and provide both some off-road and also street use benefits. When set up properly you can get a smooth ride on the road while still getting some nice flex capabilities off-road thanks to the control arms allowing the shocks to pivot and allow a wider range of motion. Most setups use 2 or 4 link arms along with an included track bar.
Coil springs have either constant or progressive spring rates in which the spring rate increases as the spring compresses to prevent the shock from bottoming out while allowing the spring to handle a wide range of forces. While being cheaper to manufacture than leaf springs, coil springs end up being more expensive because they are usually just one component of a strut assembly and have no mounting points to function on their own. You can read up more about coil and automotive springs here. They are also an integral part of a coilover or strut assembly and must be paired and weighted accordingly to work well with the shock they will be working with.
Leaf springs have been the go-to suspension setup for off-road enthusiasts for a long time and for good reasons. Installation and maintenance of leaf springs is a breeze. There are many options and methods available to lift a leaf spring system and don’t require too much work, further adding to the appeal of this system. A quick and easy lift for leaf spring suspensions is a shackle extension or lift. This requires replacing your stock shackles with extended ones to provide lift. Keep these types of lifts small and under 2″ to avoid problems down the road and don’t think your rig will be able to perform like a truck with actual suspension components like shocks and springs to provide lift.
As simple as they are, leaf springs still provide an important function on your truck’s suspension and improperly matched or badly installed parts can cause problems. Common mistakes are choosing leaf springs that cannot support the weight of the truck or getting springs that are too short or too long for your ride and trying to make them work. There are also some options for a little more customization including the type of spring eye type, including reverse, Berlin, military etc. bushings can also be upgraded and interchanged to better fit your rig.
Some leaf springs come in a multi leaf spring pack assembly. This type of assembly is also referred to as “semi- eliptical” and is what you commonly see on most trucks that do not have coil springs. Multi leaf packs are multiple leaf springs stacked on top of each other to form one working unit. The amount of leaves, sizes, mounting points and much more all effect the end result and capabilities of a multi leaf spring pack so be sure you’re getting the one that works best for you.
Mono leaf springs are simply a single leaf spring that is thick in the center and tapers off towards the edges and mounting points of the spring. These aren’t used too much anymore mainly for the amount of trouble that they cause upon failure. While a mono leaf works the same way as a multi leaf pack would, when one leaf breaks on a multi pack, the other leaves and components can support the vehicle’s weight. When a mono leaf breaks the body of the truck usually drops down on the suspension. Fun. This is dangerous by itself but combine mono leaf failure with highway speeds and the risk of damage to your vehicle and to yourself increases exponentially. That being said, it is recommended that mono leaf setups be enjoyed purely off-road.
Quarter elliptical springs kind of look like and work like a diving board. Instead of going all the way across the axle like a traditional leaf spring, elliptical springs stop and attach at the axle, thus providing the diving board type range of motion. This type of suspension system is great for off-road conditions but installation and mounting of these special systems is time consuming and is usually reserved for custom off-road only rigs.
Independent front suspension or IFS is the suspension system of choice for most modern 4×4 and off-road rigs. IFS systems are comprised of 1 or 2 “A arms” or control arms, along with a set of coilover shocks or torsion bars. IFS suspension systems are a more modern and pedestrian oriented system that provide better handling at highway speeds and a more street capable off-road setup. The intricacies of the setup are more complicated but since this is a basics article we’ll keep in simple with the main functions and benefits of an IFS. Stay tuned for later articles or feel free to reach out if you had any questions. You can read up on more suspension systems here.
Spring rate has been covered before here. Once again, it is the amount of weight required to compress the spring 1 inch (lbf/in). For all my euro and metric bros thats going to be newtons per millimeter or (N/mm). Do some research on what types of spring rates are best for the type of terrain you’re tackling and also what works best for your truck and find the sweet spot to get everything working together properly. Keep in mind your choices on springs will impact your other suspension components so be ready to make further changes if needed.
Shock Size And Selection
Shocks are a seemingly unassuming part of your suspension and are commonly taken for granted. Your shocks control the weight distribution and energy dissipation of your truck and need to adhere to some very specific constraints to work properly. Having too much or too little rebound and compression will make your ride handle like crap and any bumps or dips in the road will either feel like mountains or falling into a hole. Most manufacturers have done the math for you and your vehicle to determine what constraints work best for your truck and application but when customizing a shock assembly you’re going to have to do some math.
Running custom shocks or replacing your existing ones means having to find out what size and length shocks you will need. the easiest method would be to measure your current or stock shocks to get an idea of what works. Getting too long or too short of a shock can cause some pretty funky problems. Improperly sized and installed shocks can over extend and over compress during use, which not only damages components but puts yourself and your vehicle in danger.
Shocks that are too long for the other components can cause the springs to fall out of their perches during extension among other issues. Over extending also adds extra stress to the attached components and can also damage and break your brake and other fluid lines. Running too short of a shock can limit range of motion and cause binding or coming in contact with the springs. Mounting angles also need to be addressed. A completely perpendicular shock setup is ideal because it would be able to support the complete load resting on it. As you begin to angle your mounting points for your shock anywhere past perpendicular and you begin to eat into the dampening properties of the shock the further you go. Angled shocks are better suited to be used in conjunction with leaf springs because as the leaf spring bends and contracts will arc along the same path the shock travels to retain more dampening ability.
To shop for any kind of shocks you need to know 3 values. The compressed length of the shock, your ride height, and the extended length of your shock. Search online or take the measurements yourself if you have the tools to determine what length shocks you would need.
Bumpstops And Limit Straps
There comes a time in every off-roading man’s life where he will have to use either bumpstops or limit straps so it’s best you learn what their purposes are. Both of these devices are meant to limit suspension travel or flex. Bumpstops are in place on most shocks to prevent the shocks from over compressing and bottoming out which causes damage to not only the shock but other suspension components as well. Even though bumpstops are essentially just thick pieces of rubber, improper placement or sizing of these could prevent them from doing their job. Once again do your research on this as all makes and models have different requirements.
To determine where a bumpstop or more bumpstop is needed you would need to slowly flex your suspension to the max either over an obstacle or an RTI ramp. You should be looking for contact points between suspension and steering components, around engine components too. Keep an eye out for tire rubbing and contact with body panels too, once you know this info you can go forward and choose and install your bumpstops.
Limiting straps are used to limit shock extension and over extension. In most cases you shouldn’t have these unless you have a specific need for them or because of shock sizing constraints. You might end up installing a shock with 16″ of travel but would limit the maximum extension only to 14″ with limiting straps.
Tires should be seen first as an additional source of lift for your rig and their specially designed tread and fancy sidewalls are features that should be considered secondary. Your suspension will be doing most of the work in keeping your tires sticking to the terrain so if you’re having traction issues look to your suspension first. Bigger isn’t always better depending on what you’re getting into and the “big” standard gets raised every year as manufacturers come out with bigger and badder tires. 35″ tires are considered somewhat normal now but years ago anything above 30″ was gargantuan. Just because you can fit bigger tires on your ride doesn’t mean it’s always the best idea, if you’re sticking purely off-road go, for it but bigger tires translate to poorer road performance. Don’t be surprised if 40+” tires start becoming more common as time goes on.
Do You Need a Lift?
If you’ve ever caught yourself saying “I need a lift kit.” or “Damn I wish i had some more ground clearance for reasons.” then a lift kit is for you. Most people lift their rides for either looks, or for actual function, either reason if fine but some things should be considered for each. Smaller and simpler lifts are more for looks and fitting more aggressive tires under your truck with some light off-roading but for actual function more aggressive and expensive setups and components are required so keep that in mind.
It really comes down to if you plan on retaining the creature comforts and streetability of your truck. The more aggressive you go towards the off-road side, the less function you get from your truck as a daily driver and make it more uncomfortable in pedestrian situations.
Things to Consider
Depending on the extent of the work, lifting your truck can be pretty straight forward with some basic tools. Or worth a trip to a shop for an install. If you felt comfortable and have some prior knowledge and proper tools, nothing is stopping you from doing an install yourself but some of the unexpected headaches you encounter might be worth your money in paying for. Do not attempt any installs if you don’t have the proper tools or safety equipment.
Any type of lift you go for will begin to impact certain daily functions like steering geometry and to make some tires and components fit, body panels and components will have to be cut and welded so keep that in mind. Also the higher you go the more likely you are to be breaking some obscure law in your state so be sure to check out your local regulations to prevent any issues with the law.
For serious and extreme lifts complete overhauls of supporting components would need to happen. Gearing ratios need to be adjusted to accommodate the extra weight, steering rack extensions and upgrades, complete powertrain upgrades along with brake line and fluid line extensions will also be needed.
Now that you’ve got the basics covered you should have enough information to get started on your journey and be sure to read the other articles on the subject too!