Shock confusion??

[Team Japan]

Hi all! Can anyone help me clear up some confusion regarding shock absorbers on a 2” lift?


My Surf (’93 2nd Gen) had already been given a 2” suspension lift when I bought it. This seems to have been done with aftermarket coils and shocks at the rear, but just by winding up the original torsion bars at the front. It has never given me a problem before, but the original shocks have now worn out and need replacing. I looked at the Roughtrax website and found there was a choice – standard height or for a 2” lift – so naturally I ordered the latter. These, to be exact: http://www.roughtrax4x4.com/?doc=16&cid=997&vid=1621

When they arrived however, they are noticeably longer than the original shocks which are on the car now. In fact, when the new ones are fully compressed, they are just 7cm shorter than the old ones when they are fully extended.

When I phoned Roughtrax for confirmation, their suspension expert (Brian, I think) told me that this was because my car’s lift was done using the original torsion bars, not the aftermarket ones which form part of Roughtrax’s official lift kit: http://www.roughtrax4x4.com/?doc=16&cid=1145&vid=1163
I asked him what the difference was between the torsion bars and he told me that the aftermarket ones are “splined differently”.


Two things about this are confusing the hell out of me. Firstly, I’m sure the aftermarket bars ride better and are probably stronger than winding the originals right up, but in both cases the end result is that the wheel sits 2” further down away from the chassis, so I can’t see how using different bars to achieve the same lift can require different lengths of shock.

Secondly, the travel of the front suspension is limited top and bottom by bump stops on the chassis rail hitting on the underside of the top wishbone and the upper side of the bottom wishbone. So however the lift is achieved, unless the geometry of the suspension is changed (eg. by adding balljoint spacers), it must still sit within this range. The suspension is stiffer with the bars wound up, so the weight of the car pushes it down less far, hence the lift, but this is still within the range of the standard shocks. So I can’t understand how using either torsion bars to lift the suspension should require longer shocks.


I tried to put this to the guy from Roughtrax, but we kind of went around in circles of logic and missed points until it started to sound like I was trying to start an argument. There are only so many times you can repeat the same points before it starts to sound like you’re getting confrontational, and he was starting to sound annoyed. I wanted to keep on Roughtrax’s good side in case I need to exchange the shocks, so I backed down.

So am I completely missing something here or do Roughtrax not know what they are talking about? He did say that he’d sold hundreds of these shocks to people with 2” lifts and had no complaints, so I wondered if anyone here has used them? Any ideas or input would be highly appreciated!

[Albannach]

On the front, you don't need +2" dampers if your lift is achieved using the torsion bars alone. All that particular lift does is to move the suspension through a bit of its normal range (between the bump stops)

[Team Japan]

Thank you! That's the conclusion I had more or less come to, but roughtrax are selling the same +2" shocks as part of a kit which consists of the shocks and torsion bars alone!

http://www.roughtrax4x4.com/?doc=16&cid=1145&vid=1163

So what are the +2" shocks for? Ball joint spacers, I presume?

Cheers

[wishbone]

I'm siding with Team Japan on the arguement with R'trax.

I'd imagine that if you fit BJ spacers and a diff drop then the longer shocks will give more extension, however you may need to fit extended bottom bump stops to lessen upwards travel (I think that some shocks may come with built in bump shocks ? )

Easiest way to find out if they fit ok is to fit them, slacken the torsion bars right off and jack the hub up and down to see if the bump stops are still reached ok.

btw Team Japan - what happened to the website you and your mates had for greenlaning in Suffolk / Essex ?

[Albannach]

So what are the +2" shocks for? Ball joint spacers, I presume?

Yes, because there is a ~2" bigger gap between the bottom wishbone and the top damper mounting (the top wishbone stays in the stock position).

[TonyN]

I don't get your point, the new shocks should be longer than stock, which you said they are.

Get the standard shocks if these are to long.

The lift kits torsion bars are just uprated spring rates, (thicker) they hold the truck up higher for the same setting at the anchor end than stock bars, so the wishbones will be pointing further down so you need longer shocks. Most people cut the upper stop in half as a matter of course when you lift it.

Roughtrax's longer shocks for the lift kits will still fit most stock suspensions, have you actually fitted the shocks? You'll probably find the front wasnt lifted that much anyway when you got it, or you would have had more problems with tracking and torn CV gaiters than you have.

[NiftyNev]

Standard shock are all you need if only adjusting torsion bars. If you start altering bump stops and adding ball joint spacers for more articulation then longer shocks should be considered. That's when you need to get out the calculator and do some suspension flexing to work out exactly what you need. Don't depend on a salesman to tell you what he thinks is right.

Nev

[NiftyNev]

A pic of you suspension showing the lower control arm would be good. The gap between that and the bump stop (can you measure it?) and the angle of the control arm is a good indication of how much lift there is.

Nev

[Team Japan]

Thanks everyone for your replies.

TonyN, my point is best summed up by Albannach's first reply:

On the front, you don't need +2" dampers if your lift is achieved using the torsion bars alone. All that particular lift does is to move the suspension through a bit of its normal range (between the bump stops)

I did not know this when I bought the shocks, I ordered them while at work without looking at the geometry of the suspension. Since Roughtrax describes the +2" shocks as being for vehicles with a 2" lift, and even includes them in their lift kit, I assumed they would be correct for my vehicle. As everyone seems to agree though, they are apparently only suitable if the lift has been acheived using ball joint spacers (not part of roughtrax's kit).

I have not tried fitting them because it seemed likely I would have to return them, so didn't want to scratch the paint around the mounting holes or damage them internally by bottoming them out with the weight of the car on them.

The exact amount of lift on my car is irrelevant, because whatever it is, it's still within the range between the bump stops: even with the car jacked up off the ground so the upper arms are resting on their stops, (the theoretical maximum lift you could ever get from the torsion bars alone) the original shock still had about 1cm more of travel to extend when I unbolted it. The new shock would compress about 6cm from this position before it internally "bottomed out"; I'm sure even the most stiff torsion bars would allow more travel than this when off-roading.

So I guess my original point was that I was confused because Roughtrax insist that the longer shock is needed for a 2" lift, when it turns out that it isn't if the lift is from torsion bars alone.

Thanks to everyone else for confirming what I thought - I will see if I can swap them for some decent standard-length ones.

[Team Japan]

btw Team Japan - what happened to the website you and your mates had for greenlaning in Suffolk / Essex ?

Well, basically we posted a couple of videos of us larking around on my Father-In-Law's farm - climbing grass banks, driving through deep mud, etc - and a couple of people started sending us rude messages, accusing us of going "off-piste" from a public byway or something. We tried to explain that it was private land and we had the landowner's permission, but within days we were being bombarded with angry and sometimes very rude messages from various members of GLASS and a couple of Landrover forums. None of us wanted to deal with it all, so we closed the site down.

[wishbone]

Well, basically we posted a couple of videos of us larking around on my Father-In-Law's farm - climbing grass banks, driving through deep mud, etc - and a couple of people started sending us rude messages, accusing us of going "off-piste" from a public byway or something. We tried to explain that it was private land and we had the landowner's permission, but within days we were being bombarded with angry and sometimes very rude messages from various members of GLASS and a couple of Landrover forums. None of us wanted to deal with it all, so we closed the site down.

Hmmm sounds pretty typical these days..

[snowplower]

not for fast offroading

That was my first lift 6 yrs ago diy spacers on back and crank up front torsion bars. On a time trial every bumpy corner i went into surf went straight on into the bush because front wheels were bouncing of the ground. Wish i had thought of cutting top bumpstops and lengthening bottom ones back the, you want to have seen my paintwork after 1 month no original paint just a mass of touch up brush strokes.