Bilstein vs KYB: Entry-Level Shock Shootout

Not only do KYB and Bilstein compete for contracts with the OEs, but they also compete a lot for your money when it's time to replace those factory shocks. A lot of people will tell you a stock replacement shock is a stock replacement shock, and that couldn't be further from the truth. So let's compare these two titans to see which brand and model line is right for you.

Durability

The cool thing about many of these shocks is that you can get something on or even above the level of your factory suspension for less than the dealer would charge. Plus, most people also want to make sure they are getting the same amount of miles for the money. Although you can expect a KYB to last a fairly long time, nothing is as durable or long-lasting as a Bilstein. Bilstein is one of the few manufacturers that sell shocks that will easily outlast the rest of your vehicle. We lovingly call them "the last set of shocks you would ever need". That said, if used as intended; your KYBs should last at least as long as your stock stuff did.

Bilstein B4 vs Excel G

Both the Bilstein B4 and KYB Excel G lines are designed to be direct OE replacements, and with both brands being major suppliers to a number of car manufacturers, they definitely know a thing or two about making a good stock replacement. There is a really good chance your vehicle already has these shocks, so you can expect it to feel just like it did when it was new. And if your ride did not come with one of these shocks from the factory, both brands work to ensure they not only fit like stock but also match the stock damper curves for an essentially identical feel.

Simply put, you can not go wrong with either of these shocks. We would have to really split hairs to call a winner here, but... the incredibly high level of engineering and componentry used by Bilstein often means they perform slightly better than stock. Although the goal is to match the stock feel; if every part and piece used to get there is of higher quality than the factory stuff, you might just see an infinitesimal improvement over stock. Otherwise, a KYB will feel essentially identical to how your vehicle felt when it was new.

Bilstein B6 4600 vs KYB Gas-A-Just

Where the B4 and the Excel G are all about restoring your vehicle to how it felt off the assembly line; the Bilstein B6 and the KYB Gas-A-Just shocks are designed as performance upgrades. These two shock options achieve this performance mostly by using a monotube design rather than the twin-tube design used on the B4 and the Excel G. A monotube shock inherently has a larger diameter piston (36mm for KYB and 46mm for Bilstein), which means more damping force potential; essentially giving more support for bigger bumps and rougher surfaces, against unwanted body motions, and for carrying more load.

The differences in piston size between these two shocks also tell you a lot about their intended purpose as well. The Gas-A-Just is really meant to give you a stock-like feel in the few areas where stock suspension systems usually fall short. You gain a slight bit more big-bump support, load stability, and handling, without really losing the comfort many people prefer from their stock shocks. These are generally best suited for people who really need nothing more than what the stock suspension provides, but would not mind a little more locked-down feel overall. Since the price jump from an Excel G or B4 is so minimal, we actually recommend these more commonly, as you get a little more for your money. Even if you are perfectly fine with how your vehicle has always felt, the extra durability of a monotube design is a nice plus, as they have the potential to last a little longer than your average twin-tube.

Alternatively, the B6 line of shocks is aimed more squarely at increasing the performance of a stock-height vehicle. The much larger 46mm pistons and digressive valving do a lot more to reduce unwanted body motions in the handling department, as well as to make the car much more stable under load. Additionally, although not necessarily designed for off-road use, they seem to be a good bit happier in the dirt than the KYBs. All this added performance does come at the expense of a bit more road harshness or less small-bump compliance, but with the improvements in handling, big-bump support, and load stability, most people prefer the overall feel. That said, these are definitely the better choice for drivers who want or need significantly more out of their suspension. Although they are our preferred choice by a country mile, they also ride noticeably firmer than the KYBs, so if handling prowess, load support, and a tighter overall feel are not on your short list of needs, you might prefer the Gas-A-Justs.

Bilstein 5100 vs KYB MonoMax

As you might have noticed, the theme here is that the bigger the piston, the better, and at this level, both brands are packing 46mm pucks. Larger pistons mean greater damping force potential, allowing them to provide more overall support, something both brands take nearly full advantage of. That said, whereas the KYB was more the jack-of-all-trades and the Bilstein was the firmer choice in the last section, the roles are reversed with the Monomax and the 5100.

KYB is primarily focused on offering OE replacements first, which means the Monomax line is usually only available in stock lengths for stock-height vehicles. Although select applications offer multiple lengths for varying lifts, since the vast majority of these shocks are for applications without a lift kit, they take the added performance potential of that larger piston and apply it to towing and hauling prowess. We can confidently say there is nothing that performs as well under a load for the same money, but with that extra load support comes a firmer unloaded ride. If your goal was to spend a little more money than the more basic lines for a cushier ride, these definitely ain’t it, but if you are spending just as much or more time loaded down as you are unloaded, there is hardly a better choice for the price.

Since the B6 4600s fill the void in the Bilstein catalog for stock-height performance, the B8 5100s are generally meant for lifted and leveled applications, or in coil-over strut applications, and serve as your lift or leveling kit. Although there are stock-height options for most applications, since they are meant to be “lifted” shocks, they are optimized more for off-road use than the Monomax shocks and are a little better at managing the extra unsprung mass of bigger tires. While they still run pretty firm and will outperform everything else under a load at this price point (except a Monomax); their more off-road-oriented tuning makes the ride a little cushier than the KYBs when unloaded. So if you are spending more time unloaded than otherwise, the 5100s will be a lot easier to live with while also still being a big improvement in stability when loaded down. Basically, they are the quintessential do-it-all entry-level shocks for daily drivers and enthusiasts alike. Whether you lifted your tow pig or daily driver, want something that does not break the bank but lasts a long time to replace the junky house brand shocks your lift came with, or you want a shock that will at least be a little better than stock in every area but small bump compliance; they just flat out work.