How NOT to fit long-travel shock absorbers

One of my friends just bought himself a fourby. The guy who owned it previously did a 'Frankenstein' on his original shocks, rather than purchase new ones for the raised height spring lift.

It really is a 'shocker!'

Dave and Brenno's Excellent Adventure

David Luke and Brendan Seymour are 4WD men.

For the bulk of the week, they’re living the dream….Yep! Key blokes at 4WD Action. The world’s best 4x4 magazine.

When they’re not on the job, they keep doing what they love: Thinking about, dreaming about, building, buying, all things 4WD – and continue to get as much time as possible behind the wheel.

Above is a pic of their latest project. A highly-modified Range Rover. The intention is for use as a dedicated comp-truck. Expect to see it at many of Australia’s popular events.

The Rangie has a 351 Windsor V8, GQ diffs, A-frame rear and 5-link front suspension dampened by (6) Rancho RS9000 ride-adjustable shocks. The diff centres are locked and geared low. Power transfer is by a C4 auto box.

Top stuff guys! Look forward to hearing about your future mods and adventures.

Rancho RS9000X or RS9000XL - What is the difference?

Good question.

The Rancho RS9000XL shocks supersede the RS9000X as a series.

The RS9000XL stands out from the crowd: New look (nice metallic silver finish). New graphics (Charlie would approve). New packaging.

All new Rancho RS9000XL shocks have a beefier 18mm hardened and double-chromed shaft. Plus, the 9000XL shocks are supplied in 3 different body diameters. These are 55mm, 60mm, and 'super-duper' 70mm. Which size you get is application specific. You don't get to choose.

For example, the shocks for a 1999-2004 Ford F250 feature the 70mm body shocks front and rear. The shocks for a raised coil-sprung Nissan Patrol have 55mm body shocks at the front, and 70mm body shocks at the rear.

The 55mm body units are generally over-size compared to original-equipment shocks. A fatter shock body means more oil-content. More oil content means greater heat dissipation, so your shocks can perform at their best for longer.

The 60mm body units look really tough, and the 70mm body units look like the rockets on a military tank.

Finally, the new Rancho RS9000XL shocks are gas-charged. This means that the shocks contain nitrogen gas to pressurize the oil within the shock body. This pressure helps prevent the oil from boiling when the shock is working hard and means optimum performance in off-road conditions.

Gas-charged shocks can provide faster damping reaction times than foam-cell shocks.

For a gas-charged shock to provide great long-term performance, top seal retention is everything and the quality, fit and function has to be just right.

Bilstein gets it right with their gas-charged shocks and they provide long-term performance.

Rancho gets it right with the new RS9000XL and we put our money where our mouth is on warranty.

Where most of the shock brands in Australia feature a 2-year/40,000km warranty (whichever comes first), 4WD1 offers (on approved fitments) a 3-year warranty with no limit to the kilometres travelled within the 3-year period.

We realize that a lot of people these days travel 40 and 50,000km per year, so a 2-year/40,000km warranty is not much of an offer at all.

We would not want to offer the warranty that we do if the product was going to come back to us - especially given our roads and user type.

All the other amazing features of the 9000X and RS9000XL shocks are the same. You can find out more here

Rancho RS9000XL shocks | What is the best setting and how to adjust them.

Sam’s not only smiling for the camera. He’s adjusting the ride-firmness of his front Rancho shocks. They’re RS9000XL’s, and as you can see, you just reach in, twirl a dial, and it’s done.

RS9000, RS9000X or RS9000XL shocks have a small ride-adjustment knob fitted to their base. You simply turn the knob with your fingers. No special tools are needed, and you don't need to remove the shock from the vehicle in order to make the adjustments.

Usually it takes 60 seconds to go around and adjust all four units.

The adjustment knob has numbered settings embossed into its face. There are nine positions to choose from. The change in stiffness is no gimmick. There is about 800% difference between the softest setting and the firmest.

Number 1 (softest setting) can be set by twisting the knob as far as possible anti-clockwise. Firmer settings are achieved then by turning the knob clockwise. Position 9 is the firmest.

After you have been off-roading, chances are they could be covered with dirt, grime, or mud, making it hard to see the numbers embossed on the ride-adjustment knob, or the alignment arrow mark stamped into the shock body.

Don't worry. Remember, twisting the knob as far as you can go anti-clockwise takes you to the softest setting (number 1). Then, you can feel the clicks when turning clock-wise from there ( 2-3-4-5' etc.) so you will know which setting you are at. This means that even with your eyes closed, you can adjust the shocks precisely to your personal preference.
Which settings are best for certain purposes?

Usually you make adjustments to the shock, based on four variables.

(1) The amount of weight or load carried. This includes accessories fitted, passengers, gear, tools and towing. Extra weight places greater demand on your 4WD's springs, requiring more control or damping from the shocks to ensure good stability. Typically, under heavier loads, you are using a setting between positions 5-9.

(2) The speed you are traveling verses the terrain type. For example, highway and freeway driving is typically high-speed work and the roads are smooth. In this instance, look to firmer settings for more sports-car like handling. Firmer settings provide better control at high speed, and because the roads are smooth, little spring action is required - so tight control over the springs is OK.

(3) Inherent characteristics in a vehicle type. Like people, most vehicles have their quirks. Suspension systems not excluded. (Too soft. Too stiff. Too jerky etc.) On some vehicles with IFS (independent front suspension) there’s often complaint about how soft the front-end control and handling is. With the Rancho adjustable shocks fitted, you can dial the units firmer to compensate to a reasonable degree. Or, if the vehicle's springs are notably stiff, you can soften the shocks in a lot of circumstances, for a much more comfortable ride.

(4) A combination of all the above. Driving on gravel and corrugated roads often requires good control and handling (firmer settings), yet some 'give' in the suspension (softer settings) is also required or the vehicle may track and skitter.

To achieve the best compromise between control and comfort, the load in the vehicle, the speed you are traveling at, and the inherent characteristics of the vehicle all play a part in deciding which settings are ideal.

From experience, in any situation, you are always looking for as comfortable as possible, while maintaining good stability. Mantra... You are always looking for as comfortable as possible, while maintaining good stability.

I recommend that when you first receive your Rancho RS9000XL shocks, set them to mid-range (position 5). This is probably closest to the amount of control you get from the original factory-fitted shocks. Then, from this mid-range setting you can simply 'up' or 'down' the shocks according to your needs.

Don't be afraid to try different settings front/rear. Usually our customers will play with the shocks like a kid with a new toy for a few days. Then they will have confidence in the settings that they choose.

If externally ride-adjustable shocks sound too complicated, too fiddly or too much hassle, remember only a little bit of experience is required before you master the settings.
Plus, if you purchase another type of shock, and don’t like the way they ride – what do you do?

Why shock absorber shields for 80 + 100 series Toyota Landcruiser?

If you own an 80, 100 or 105 series Landcruiser and you like your off-road touring, it pays to consider the fitment of your rear shock absorbers.

Both shocks sit forward of the rear axle, and it seems that everything that the front tyres travel over lands on them.

Regardless of the qualiy of the shocks, or whether they are double or tripple-tube, if you flick up a rock the size and shape of an axe-head: That's the end of the shock absorber!

So if you travel gravel, shield your rear shocks from stone-spray and rocks (wasn't mean't to rhyme)

Don't use rubber or similar tp cover the shock body, as it will trap heat and may also cause the shock to fail.

How do I work out the best length shocks for my 4WD?

Daily, we get calls and emails from people that go like this:

"I've got a (-insert your vehicle here-) with a 3" lift kit, and I'm chasing shocks that extend out 3 inches more than original, but compress down to the same amount as the factory shocks..."

It's not an unreasonable question. I can see the logic here. Unfortunately (in practise) it's wrong.

Firstly, lets assume that a vehicle fitted with a 3" suspension lift kit, will benefit from 3" longer shocks (more about this in a minute).

You can't have a shock that is 3 inches greater in extended length, yet compresses to the same body length of the original unit. This is because the shock body (which is your compressed length) must be greater in order to allow for the increase in rod length (extended length).

Memorise this.

- The body length of the shock must be greater in order to provide the increase in rod length (extended length).

- The body length of the shock must be greater in order to provide the increase in rod length (extended length).

- The body length of the shock must be greater in order to provide the increase in rod length (extended length).

The extended length of a shock, is determined by the length of the chromed piston rod, combined with the length of the shock body itself. On full compression, the chromed piston rod is contained within the shock body.

If we made say, just the chrome piston rod longer, and left the shock body length the same, on full compression of the suspension, the shock's chrome rod would simply smash through the base of the shock body.

Game over.

Back to the bit about needing shocks 3 inches longer, for a vehicle with a 3" suspension lift....

Perhaps your 4WD does need such an application. However, often this is not the case.

On the lifted vehicle, the extra movement or travel between the shock mounting points may be minimal. This can be due to the way that the suspension is configured relative to the positioning and angle of the shocks to the axle and the wheel.

It may be that the sway-bar mechanics on the vehicle are holding the travel of the suspension back (rather than the shocks).

It could be (in the case of heavy-duty springs) that the extra spring rate creates less flexibility in the suspension, negating the benefit of fitting a longer shock.

If we go ahead and fit the 3" longer shock (in the case of a coil-sprung vehicle), the coils may not remain captive on extended travel (the coil falls out).

That's a big deal.

On compression travel (because the shock body is longer) you might crunch (destroy) the shocks, as the vehicle's suspension pushes down past what the shock body length specification will allow.

Ouch!

If the longer shocks do allow for more suspension travel than original, your brake lines may be too short (stretch and tear).

You might put extra load or tension on your sway-bar. In some cases, your drive-shaft or tail-shaft may pull apart.

I'm not a drama queen (really), so this is how it works...

On most popular Australian-sold vehicles with a suspension lift of up to 50mm, the shock absorber length supplied (in almost any brand in the marketplace) is about the same as the original unit.

This is because in most cases there is sufficient travel in the shocks stroke to allow for this type of lift. Particularly as the amount of stretch between the shock mounting points is usually less than the amount of suspension lift height.

I'm not saying you can't get extra travel by fitting a longer shock, but the modifications and checklist involved are usually more than what the average family-orientated 4wd owner wants to be involved with.

"But I want maximum travel!"

OK. I hear you.

If your vehicle can benefit from fitting longer shocks, and you are happy to do what you have to do to make it work - here are some guidelines to start with.

First, determine the suspension travel your vehicle is capable of with no shocks fitted (none). You usually need to drive your vehicle up onto a dedicated travel ramp. If you don't have access to a travel ramp, you can achieve the same thing by jacking up each corner of the car with a forklift (one corner at a time), or finding some off-road terrain (or adapting some) that allows you to fully work the suspension.

Do this with great care. Regardless of the method that you use, you don't want the vehicle to roll over and crush you. In the case of a coil-sprung vehicle (as the shocks are removed) you don't want the coils to drop out.

Record the distance between the shock mounts at full suspension travel, for each direction of movement.

Also for reference, measure the distance between the shock mounting points while the vehicle is parked on flat ground. This measurement is called the 'static' or 'rest-height' position.

Then work with your supplier of shocks for the closest match in an appropriately valved product to both the open and closed measurements. The closed (upward travel) is just as important as the extended (downward travel). This is because in the case of a solid-axle suspension system, one side of the vehicle must be leveraged up in order for the opposite side to be pushed down.

Traditionally, a technically perfect application sees a shock absorber opened to the half-way position while the vehicle is parked on flat ground. So, if a shock has 10 inches of travel, the shock (at normal ride) would have the ability to extend out 5 inches before coming to the end of its travel, as well as compress 5 inches from the normal ride height position before crunching the shock.

A technically perfect application is not always possible, due to shock length availability, or the travel characteristics of the vehicle (may have more travel in one direction than the other). Essentially, as long as you have optimum travel in both directions, according to what your vehicle is capable of - you have a good long-travel shock application.

I mentioned earlier about modifications required to fit genuine long-travel shocks.

In most cases, extending the axle bump-stops is required. This is to protect the shock from 'crunching' and becoming damaged on full compression of the suspension as ...the body length of the shock must be greater in order to provide the increase in rod length (extended length).

Extending the axle bump-stops means you are reducing the bump-stop gap, so the rubber bump-stop makes contact with the metal striker plate before the shock crunches into itself. Extending the axle bump-stops (reducing the bump-stop gap) sounds counter-productive to the intention of maximising wheel travel.

The benefit of doing so (together with the longer shocks) still outweighs the performance of a vehicle fitted with a suspension kit and factory-length shocks - particularly in the case of bigger lifts.

A way of eliminating the need of extending the axle bump-stops can be to relocate the 4WD's shock mounting points, so that they are spread further apart. Weld-on shock hoops are one example of how to do this. It means that you can fit a shock with a massive amount of travel (more travel than what the vehicle is capable of in any direction).

So here, no need for extended bump-stops or inefficiencies in travel. No need to worry about crunching the shock on full compression of the suspension.

Next, check your brake lines. Purchasing extended-length ones is often required, because the suspension may now articulate further than factory design.

Check (in the case of a coil-sprung vehicle), that the coils remain captive (can't fall out) under the full travel of the suspension.

Check the stress on the other related components on the vehicle such as sway- bar and link pins. If you fit longer link pins or extend the original ones, this might alleviate some problems - It might also create new problems too!

The extra suspension travel available may also mean that parts of the suspension or axle may make contact with other parts and accessories on the vehicle.

You will need to counteract and compensate for this. Lots of extra travel can even allow your CV's, drive-shaft and tail-shaft to be damaged, slip out, or fall apart.

Again, you need to compensate for this.

All the things you need to do and check for are beyond the scope of this post.

Also, (and this is where I have to do the legal talk) you need to make sure that any modification you make to your suspension will not affect the safe and reliable operation of the vehicle, or contravene any applicable regulations, rules, laws or insurance requirements.

This is your responsibility. Don't shoot the mail-man!

An alternative we could look at to eliminate a lot of hassles associated with long-travel shocks, is if we started to make them out of rubber. This way, a customer could simply stretch the new rubber shock out and in to whatever length they want.

They could get the exact open length they would like, together with the ideal closed length they wish for also.

It would be good business sense for us too. We would only need to stock one part number on the shelf, rather than the hundreds of different part numbers we currently do.

I'd probably get a raise!!!

So, if you are interested in purchasing the new rubber shocks for your next suspension application, please click here.