2003-2009 Lexus GX 470 & Conversion Kit Technical Description

 

Introduction

With the introduction of the GX 470, Lexus brought forth a vehicle that exemplified everything that has come to define the brand—tasteful styling, concierge-level luxury and consistent, reliable engineering—while it also pushed it into new territory as an extraordinarily capable four-wheel drive vehicle.

Celebrated for its smooth ride, spacious and luxurious interior and surprisingly robust off-road capabilities, the GX 470 was enjoyed enormous popularity during its run.


Performance and Tech

Produced from 2003 to 2009, the Lexus GX 470 in many ways was a traditional SUV—bulky, heavy, boxy and highly-capable.

Under the hood, a 4.7-liter V8 produced more the enough power to keep things moving, putting out between 235 and 270 horsepower depending on the model year. A five-speed automatic transmission and full-time four-wheel drive system with low-range gearing was standard throughout the vehicle’s lifetime.


The GX 470 was packed with a number of features that separated it from the pack (as well as its close cousin, the Toyota Landcruiser). The SUV was consistently praised for its off-road capability, helped in part by these features, such as Hill-Start Assist Control (HAC), Rear Adjustable Height Control (AHC) and Downhill Assist Control (DAC).


Design

Fans of old-school, traditional SUVs were probably delighted with the GX 470’s exterior. The tall, boxy body-on-frame design bears a lineage to the 4Runners and Landcruisers of yesteryear, vehicles which were certainly more utility than sports.

The GX 470 was, however, still a Lexus. That means luxury and refinement at every turn: huge, plush sheets draped in fine leather, woodgrain everywhere woodgrain should be and a high-end Mark Levinson-branded audio system.

The interior provided plenty of room for the first and second rows, reminiscent of an airplane’s first-class seats. Passengers could expect a spacious and quiet ride, with the vehicle’s ride height and solid construction all but eliminating road noise.

One major complaint with the GX 470 was a rather measly third row—perhaps big enough for children or pets but majorly cramped for anyone beyond their teenage years.

Safety

Designed to be a family vehicle, the GX 470 went heavy on the safety features. For starters, it was one of the first vehicles to feature an optional rear back-up camera system, beginning with the ’04 models and integrated into the SUV’s onboard navigation system.

Standard safety features included a roll-sensing feature that could deploy side-curtain airbags and a tire-pressure monitoring system.

The GX 470 scored well in IIHS safety testing, earning a “good” rating in seven out of 10 categories, performing especially well in front-end testing and overall structural categories.

Specific Information on Suspension System

The GX 470 used air springs in the rear of the vehicle to complement its off-roading capabilities. In addition, the vehicle allowed for automatic self-leveling or driver-selectable height controls in the rear. The luxury SUV also featured an automatic hill holder—a feature which prevents rollback when the vehicle is stopped on an upward slope—along with a driver-enabled automatic speed limiter which assists with steep descents.

Beginning in 2004, Lexus also offered the innovative Kinetic Dynamic Suspension System (KDSS). This state-of-the-art feature automatically adjusted the car’s front and rear stabilizer bars to tailor its handling to a variety of different on and off-road situations.

Potential Issues

While the GX 470 had its share of fans, the vehicle had a number of oft-cited problems.

For all its off-road capability, Lexus never really seemed to get the on-road ride just right. While the GX 470 could dutifully climb over any rock or hill in its path, passengers were acutely aware of any little dip or bump in the road—a perplexing problem for a 4,500-plus pound luxury vehicle.


Like most air suspensions, the GX 470’s air suspension functioned great when it did but served as a ticking time bomb. One of the vehicle’s most consistent problems was it’s ride-height sensors, which reportedly went out much earlier than on many of its competitors. These sensors alone cost nearly $500 each to replace and were absolutely essential to the proper functioning of the entire suspension system.

The air suspension itself was often identified as having problems much earlier than expected, likely due in part to the vehicle’s weight and perhaps overly rigid on-road suspension.

For all its innovation, the KDSS was a highly complex system on top of an automatic self-leveling suspension system that was complex enough in and of itself. As with most things, more moving parts meant more chances for things to break.

The problem of high-tech air suspension systems not lasting was not a new one or something unique to the GX 470. These problems were inherent in most mid-size to large SUVs, with suspension failure being an inevitability for anyone putting any real miles on the vehicle. In reports that are backed up by the Motorist Assurance Program, many owners of the GX 470 and other vehicles in its class reported a drop in functional ability after as few as 35,000 miles, with nearly all reporting a major degradation of function after 50,000 miles.


Problems With Driving on Worn-Out Shocks

When the shocks start to go, the first thing drivers will begin to notice is a decrease in the comfort of the ride. In a large SUV, this is especially noticeable. Small bumps in the road begin to cause more and more jostling on the interior, providing a rough ride where there used to be a smooth one.

Comfort issues often go ignored as a smooth ride might be seen as a dispensable function of a car—more a convenience than a necessity. However, these early warning signs are key. If suspension problems are left unattended, these problems can spread quickly throughout the vehicle and have an exponential effect, drastically reducing the lifetime of the vehicle.

The Nose Dive

One of the most tell-tale signs of worn out shocks is the dreaded “nose dive.” This is when the vehicle loses the ability to distribute weight evenly when stopping, resulting in the front end of the car dipping down and the rear end of the car lifting up.

Nose-diving can cause a myriad of issues with any car, let alone a two ton-plus SUV. One of the principal problems caused by nose-diving is the buildup of excessive heat in the brake mechanisms. This will first cause the brake pads to deteriorate rapidly, noticeable by a “spongy” feeling in the brake pedal. The wear on the brake pads will significantly reduce stopping power which is a major safety issue. The buildup of heat can also cause other parts of the brakes to lock up or lose functionality quickly.

Tire Cupping

Cars driving on shocks that aren’t functioning properly will experience a form of tire wear known as “cupping.” Cupping occurs when bumps or divots in the road cause the tire to lose contact with the road—a common occurrence when driving on worn-out shocks.

This jostling up and down causes excessive and uneven wear on the tires as they scrape and bump over uneven road surfaces rather than glide over them as intended. This type of wear will produce rapid deterioration of the tires and a need for a replacement well before the full extent of the manufacturer’s suggested lifetime.

Other Issues Abound


It is important to recognize that a car is built with the idea that all of its parts will function as intended. In this sense, all parts of the car are dependent upon each other to do the job that they are designed to do. Knowing this, it should be no surprise that once the shocks go, other parts of the car are asked to pick up the slack and take on more stress than they were built for.

Within the suspension system alone are bushings, CV joints, ball joints and stabilizer links that depend on the struts to do their job. After the struts have surpassed their useful lifetime, these pieces are forced to take on the role of absorbing the road stress that the struts no longer can. This will cause these pieces to deteriorate much more rapidly than if all of the car were to be functioning normally.

These issues go far beyond the comfort of the ride and cost of replacing these cars. While airbags, anti-lock brakes and other safety features tend to get the recognition, a vehicle’s suspension system is perhaps its most important safety feature.

Any loss of functionality in the suspension system means a vehicle will lose its agility and maneuverability, making avoiding potential accidents much more difficult or simply impossible. A bad suspension system will also significantly increase the risk of rollovers while taking corners.

Perhaps most alarming, however, is the reduction in stopping power. Research has shown that a car traveling at 70 mph requires at least 22 extra feet to stop versus the same model car with fully-functioning stops. This can mean the difference in having an accident and not having an accident, or between a minor fender bender and a fatal rear-end collision.

Making the Switch

High-tech suspension systems like the one employed by Lexus are marvelous as long as they are functioning normally. However, these systems have shown time and time again that they will fail, it’s just a matter of “when.”

As mentioned previously, replacing just the sensors on these systems can immediately set a car owner back a thousand dollars or more. All told, replacing just the rear suspension with the manufacturer’s original system will cost at least a couple thousand dollars, most likely a very significant percentage of the value of the vehicle at that point in its life. At this point, many owners do the math and decide they would rather cut their losses and simply get rid of the vehicle in favor of a new one.

The manufacturer’s original system, however, is not the only answer. Strutmasters Inc., the industry’s leading suspension replacement experts, have developed a simple, robust and inexpensive conversion kit for the Lexus GX 470 and others. These coil-based conversion systems can replace the rear shocks on the SUV for a small fraction of the cost one would pay at the dealership or at a shop using the manufacturer’s original air suspension.

Rather than using high-tech computers and sensors, these conversion kits leave the job of dampening the ride to hearty, high-quality mechanical parts that are easy to install and understand.

High-quality components means high-quality performance

Stronger Steel

When it comes to dependability, chromoly tempered steel is the only option one should consider. Celebrated across a number of industries for its ability to resist corrosion and extreme durability, chromoly tempered steel is the only material Strutmasters uses to make its struts. Each piece is specially treated to reduce friction and precision-ground to ensure long-lasting seamless functionality. The result is shocks that last longer and perform better than most of their competitors.


Better Seals

Seals are one area where manufacturers may look to cut costs, given that they are small and usually not immediately visible. Small as they may be, seals are essential to the proper functioning of struts. Cheaper seals will wear out quickly and transfer that wear and tear to the struts themselves.

Strutmasters uses only top-shelf seals made with the highest-quality materials available. These seals will continue to block debris, dirt and other contaminants from entering the functional areas of the strut throughout the lifetime of the strut itself. In addition, these seals will maintain the ability to hold fluids and gas charges for far longer than their competitors.

High-grade fluids

Hydraulic fluids—an essential component in the proper functioning of struts—can vary wildly in quality. As a result, manufacturers will sometimes skimp on this highly crucial element, resulting in less-than-ideal functioning.

Struts ask a lot of their hydraulic fluids. During periods of high usage, parts within a suspension system get extremely hot. Over the course of 12,000 miles of driving, the struts will experience 21 million stabilizing cycles. These up and down cycles, called compression and rebound cycles, require a lubricant in order to function properly. Over time, this buildup of heat will destroy the elasticity of this grease, similar to how motor oil breaks down over time.

Lower quality fluids experience this much more quickly and unpredictably than their higher-quality (and more expensive) counterparts. Knowing this, Strutmasters insists on only the highest-grade grease to ensure optimal functioning for years to come.

All Charged Up

Strutmasters conversion kits use struts that are filled with pressurized nitrogen. The purpose of this pressurized gas is to maximize dampening performance. Also, this gas prevents what is known as “cavitation,” or the formation of air bubbles and pockets within the system. This cavitation can cause a number of often very dangerous problems. Proper sealing of this gas is therefore essential to proper safe functioning of the struts.


No Bottoming Out

When the strut’s shaft goes deep enough to hit the bottom of the valve, this is known as “bottoming out.” This action puts a tremendous amount of stress on the valving hardware and can quickly and significantly reduce the functionality and lifetime of the whole system.

Strutmasters uses a combination of an internal shaft spring and a high-grade rubber bump stop to virtually eliminate the possibility of bottoming out.

Always in Tune


When using coil shocks, proper tuning is indispensable for correct functioning. The coil springs in Strutmasters kits do the majority of the dampening work. Every vehicle is unique in the way it rides and what it asks of its suspension. Therefore, each kit must provide a different, specific level of dampening support. This is where tuning is important. Properly tuned shocks will provide a vehicle with precisely the amount of support it needs to have a smooth, predictable ride. That’s why each Strutmasters kit is tuned and tested meticulously to ensure the proper ride for that specific make and model. The result is a ride that is equivalent to, or in some cases, superior to the day it rolled off the lot.

Made with genuine Eibach springs

When it comes to compression springs, one name rises above the rest—Eibach. The German company has a long and storied past as the compression spring manufacturer of choice for automobile professionals around the world, from mechanics to racing champions from such prestigious racing series as F1, CART, WRC, NASCAR and Indy Car.

Strutmasters believes that if these springs are good enough for high profile racing, they’re good enough for a family car. Sharing a similar philosophy with Eibach: an insistence on performance, durability and overall quality, it makes sense that every Strutmasters conversion kit come with genuine Eibach springs.

Glide-Ride technology

Ultimately, Strutmasters conversion kits are a total package that is made up of a few different components. These components need to work together in harmony to ensure absolute maximum performance and comprise Strutmasters’ patented Glide Ride ® technology.


Glide Ride ® technology guarantees drivers a low-cost replacement for their worn-out OEM struts that works as a unit to provide a long-lasting smooth ride for drivers.


Quality assured

In order to assure quality to customers, Strutmasters needs to be certain of the quality of the manufacturer. Strutmasters undergoes relentless quality assurance procedures to ensure full confidence in each of its manufacturers. It is a need for quality, not the cheapest price, that drives this process. As a result, Strutmasters customers can rest easy knowing that these conversion kits are produced only by well-vetted, trusted manufacturers.


No “discount mounts”

Each strut has a mount which attaches it to the frame of the car. As one would expect, this can be a real problem point for poorly-manufactured or poorly-fitted parts.

This mount features a small rubber piece that is its primary defense against wear and tear. Being such a small, relatively inexpensive piece, this part is one of the ones that often goes overlooked in the engineering and manufacturing process. Many manufacturers will simply place the cheapest piece they can at this part, figuring it to be replaceable or even ignorable.

Cheaper rubber degrades easily, and soon after installation struts that are mounted with these parts will begin to see a loss in function. Strutmasters kits, on the other hand, use only high-grade rubber to insulate these joints, ensuring a long, predictable lifespan for the entire kit and car it’s attached to.

Bearing the load

A car’s bearing plate is what serves as a steering pivot when the vehicle’s wheels are being turned. These bearing plates end up absorbing much of the load-bearing stress of the car during turns as a result.

Cheaper kits often use ball bearings that are made from synthetic materials like plastic, which are simply not appropriate for such a heavy-duty job.

Strutmasters uses heavy, robust ball bearings made of tempered steel, ensuring a long, problem-free lifetime.

Better bushings for a better ride

At the bottom of these strut assemblies is a bushing that connects the strut itself to the rest of the strut assembly. As with any point of contact, high-quality materials and top-shelf manufacturing are unduly important to it functioning correctly.

Therefore, the bushings in all Strutmasters kits are made a superior rubber that ensures the suspension will perform as needed and that the car stays properly aligned.

Made in the USA

As a company that is proud to call the United States of America home, Strutmasters recognizes the importance of both the American auto industry and the importance of supporting domestic manufacturing as a whole. Strutmasters also believes that “Made in the USA” is as a good, reliable stamp of quality.

Choosing to do business with American manufacturers also allows Strutmasters to develop tight-knit relationships with its suppliers and maintain direct communication at every step of the way. With its manufacturing partners just a phone call away in the same country, speaking the same language with the same business customs, the company can confidently and easily resolve any possible issues that may arise.

Most importantly, by keeping its business in the United States of America, Strutmasters can continue to support American workers and keep its money within its borders.

Rigorous testing

Strutmasters takes the performance and safety of its products seriously. That’s why the company employs professional drivers to rigorously test every single one of its products before putting them out on the market.

These drivers are capable of pushing these suspensions to their limits, knowing that if they can perform to the standards of world-class drivers, they’ll work well for the average driver on the road.

Installation


Conversion kits produced by Strutmasters require no modifications to the vehicle to install, meaning they can easily by done at home by a relatively competent DIY mechanic. For those without the tools or time to take care of installation at home, the ease of installation means fewer expensive labor hours in a professional shop, resulting in even bigger savings.

Each kit is matched with an installation guide and online training video, making installation an easy, inexpensive fix for just about anyone.

Lifetime warranty


Strutmasters stands by every single one of its conversion kits with a limited lifetime warranty. While the company has undergone every possible test to ensure maximum performance and longevity, it is proud to offer this warranty as a vote of confidence to all of its clients and customers.

Customer support

Many competitors stop service after the point of sale as a way to save on internal costs. However, Strutmasters understands that it is people who make the business. That’s why there is a professional support team at the ready to help out, whether a customer has purchased a small component or wholesale kits.

Whether it’s a specific question about a kit or just general suspension advice, the Strutmasters team of suspension experts is on duty for extended business hours, ready to help.