The Basics of Shocks
July 9, 2020
When it comes to picking out a suspension lift, many of the kits will either have a specific shock that is already tuned to your particular vehicle and application, or they will give you an option to upgrade the shocks. And many times we'll get questions through our customer service team asking about the different types of shocks and what makes them perform differently. Well here's a blog for all of you to help answer those questions ahead of time.
To start, shock absorbers do exactly what their name is. They absorb the shocks and bumps from the road or trail. Pretty simple, right? But when we start looking at the different types of shocks, how they are made, and why some perform better than others, it turns into a much more complex science that could literally turn into a college course of understanding shocks. Fortunately, we're gonna start with the basics, and then with each future blog on shocks, we'll get more detailed and in-depth on the science behind how shock absorbers perform the way they do.
1. Mono-Tube Shocks
One of the most common types of shock absorbers included with most of the suspension lifts we have is what's called a mono-tube shock. First developed in 1954 by Bilstein, the mono-tube shock has a single-piston with hydraulic oil on one side of the piston and a pressurized gas on the other side of the piston, which is typically a nitrogen gas. The hydraulic fluid helps with dampening the forces from the bumps by slowing down the up and down travel or compression and rebound of the tire and wheel, and also helps dissipate heat energy that is created from the constant motion of the piston. The pressurized gas will also help with the dampening and absorption of the bumps and really helps those hard shocks or jolts from the road or trail.
Also, the single-piston mono-tube shock doesn't allow the gas and oil to mix together as a twin-tube shock does. A twin-tube shock is a lower performing variant of the mono-tube shock and is more common in non-performance-oriented passenger cars and trucks. Twin-tube shocks cost less than a mono-tube shock. And the twin-tube design will allow the gas to blend with the hydraulic fluid, which after extended abuse and torture will create air bubbles in the oil called cavitation and will cause the piston to move much more freely rendering the shock virtually useless in what is called shock fade. Hence the reason off-road suspension companies, use mono-tube shocks or bypass shocks and not twin-tube shocks as shock performance is vital for off-road performance to keep the tires planted on the ground and the suspension under control.
2. Adjustable Mono-Tube Shocks
A common upgrade in shocks with most suspension companies is an adjustable mono-tube shock, which usually has an external reservoir. External reservoirs can either be piggybacked onto the shock body or mounted remotely and will have a rubber hose connecting the shock body and reservoir. Adjustable shocks have a dial that is used to control the valving of the piston and it controls the fluid movement to give either a smoother on-road feel or allows the shock to perform better while off-roading.
Also having an external reservoir allows the shock to hold a larger amount of oil to or better absorb and dissipate the heat. There are also differences in the size of the shock body and the material that the shock body is made out of. Hard anodized aluminum is often used to help dissipate heat much better than steel shock bodies, and is much less prone to rust,. The size of the shock body is also important to the dissipation of the heat as a larger shock body will allow a higher capacity of fluid along with a larger surface area on the shock body to allow the shock's heat to escape better. Another advantage to a larger shock body is the ability to have a larger piston rod, which is less prone to breaking when hitting really hard jumps or severe jolts.
3. Coilover Shocks
Then there is also what is known as the coil-over shock. The shock body consists of mounting points for the coil spring to have an all-in-one shock and coil setup. This allows for a much more compact setup where space can be an issue and also allows for more tuning ability to set the preload tension on the Springs. Coil-overs are offered in a variety of stroke links with configurable mounting options for the coil springs. The shocks themselves are also typically the mono-tube-type shock, and we'll often have a remote reservoir as well.
4. Bypass Shocks
Then one of my favorites is the bypass shock. A bypass shock is designed for ultra-high performing off-road rigs because of its exceptional ability to dissipate heat, and are often the main shock absorbers for trophy trucks, ultra-Ford cars, and many other rigs that are designed to go fast and harsh terrains. They also have an almost unlimited amount of adjustability to really get you the exact ride and performance you're looking for on your rig. Plus, unless you completely destroy the shock, they are also rebuildable, which in most cases will help save you some coin over the long run.
So when you guys are shopping for a suspension lift and you click the option to upgrade the shocks, and one of the options is a 2.0 aluminum body shock with remote reservoir or a coil-over shock, or even just a nitrogen gas charge shock upgrade, hopefully, you'll remember this video and it will help you out in one way or another in choosing your next shock upgrades.