Outer Limits 4x4 Board

I have tried searching to no avail...nothing I found really answers what I want to know.

HJ60 currently running a 2" suspension lift from ARB. This was installed a few years back and now I wanting more travel...arent we all

But the budget wont allow for anything major major at the moment, so I am happy to gain a little at a time if needs be. I am replacing the shocks soon as they are stuffed. But its the leaves that need the attention I think.

Hope you guys can help...because in this regard...I am somewhat of a rookie!

Seen these on ebay

http://cgi.ebay.com.au/ws/eBayISAPI.dll ... %3AIT&rd=1

in the rear, pull the 2 load leafs (the flat ones at the bottom)

you are aware pulling leafs will end up dropping your ride height aren't you?

flex it up with shocks, measure, and then flex it up without shocks, should tell you if your shocks are limiting.

does it still have swaybars?

general rule forshackles, if you make em too long they don't flex as well. so a rough rule i've been told is measure the spring dead flat eye to eye. then add about 25mm to that length.

then measure the distance between the spring hanger and shackle hanger

now the shackle length (between pins) should = (spring + 25 mill measurement) - (distance between hangers).

you've got castor wedges in your front end fro the looks of things. i heavily suggest getting castor measured before playingwith shackle length on the front, as it'll mess your caster up. if your caster already needs wedges, longer shackles will mean bigger wedges, and that means you need spring pins with longer heads on them

As Canada has stated removing leaves from your current leaf pack will reduce it's static ride height. The set up on your steer axle spring looks ok but is hard to define without knowing leaf thicknesses (will determine spring rate). If you are not happy with the steering axle suspension performance then I would suggest removing the bottom leaf from the pack, this will result in additional compression with minimal ride height reduction. The rear axle suspension is a little more difficult, If you know the constant mass over the rear axle then the job can become a little easier. The second stage leaves (2 x bottom straight leaves) should be removed and the bottom 3 three leaves in the primary stage should be cut at either end to produce a uniform step betwwen them. Have the bottom leaf finish at approx 250 (front end) x 300 (rear end). This will only be statisfactory for constant 100 to 150 kg constant loads. Because the ride height will be reduced a hot reset will be required to maintain static ride height, the hot reset process will also recrystallise the steels grain structure (providing it is sent to spring resetters that are also spring manufactures that provide heat treating as a service) and result in a spring that will provide proportional compression and rebound performance whilst maintaining a longer fatigue life. If this is all to difficult (and expensive), I would suggest calling a suspension provider that can inform you on your vehicles application and outcomes, talk to trademan and not saleman.

thanks very much for the detailed responce you guys...certainy give me lots to think about.

bad_religion_au...I took the measurements you mentioned and this is what they are...

Shackle length (pin to pin) = 140mm

Spring length (flat) + 25mm = 1135mm (that is eye to eye)

Hanger to shackle distance = 1050mm.

Now given these measurements....it reads like this

140mm = 1135mm - 1050mm.

That obviously is incorrect as 1135mm - 1050mm = 85mm

So to get the formula correct (or close to) I would have to either...

A) increase the spring length to 1165 (allowing for the 25mm addition)
B) shorten the shackle length to 85mm
C) shorten the length in between the 2 hangers to 995mm.

Am I correct in saying that option A would be the better of the three??

and if so....would there be any benefit to getting the main leaf made even longer again?

I am not going to put longer shackles on the front as the 2" extended draw enough unwanted attention as is!

With the rear suspension, I am heavily leaning towards fitting the same 2" entended shackles...and if I am correct above...fitting longer main leaves to bring the equation of yours to near spot on.

Also...would fitting wheel spacers assist in downwards travel?. In my mind it would...but lots of things go through my mind.

I am getting the truck chopped into a dual cab at the end of march, so I might wait till that is done...weigh the back end to find out constant load weight, and then go fom there in regards to removing leaves...does that sound like the best way to go about it (in regards to rear)

G_loomis wrote:thanks very much for the detailed responce you guys...certainy give me lots to think about.

bad_religion_au...I took the measurements you mentioned and this is what they are...

Shackle length (pin to pin) = 140mm

Spring length (flat) + 25mm = 1135mm (that is eye to eye)

Hanger to shackle distance = 1050mm.

Now given these measurements....it reads like this

140mm = 1135mm - 1050mm.

That obviously is incorrect as 1135mm - 1050mm = 85mm

So to get the formula correct (or close to) I would have to either...

A) increase the spring length to 1165 (allowing for the 25mm addition)
B) shorten the shackle length to 85mm
C) shorten the length in between the 2 hangers to 995mm.

Am I correct in saying that option A would be the better of the three??

and if so....would there be any benefit to getting the main leaf made even longer again?

I am not going to put longer shackles on the front as the 2" extended draw enough unwanted attention as is!

With the rear suspension, I am heavily leaning towards fitting the same 2" entended shackles...and if I am correct above...fitting longer main leaves to bring the equation of yours to near spot on.

Also...would fitting wheel spacers assist in downwards travel?. In my mind it would...but lots of things go through my mind.

I am getting the truck chopped into a dual cab at the end of march, so I might wait till that is done...weigh the back end to find out constant load weight, and then go fom there in regards to removing leaves...does that sound like the best way to go about it (in regards to rear)

Yep i failed to notice the extended shackles woops

ok yep, depending what your comfortable with, option A or option B.

with option a you've got 2 choices...

get the added 50mm put in the shackle end. this will get your shackle angle right, but add a little to approach angle.

option 2 is get the 50mm put into the rear. this'll give better flex, extend your wheelbase, and not change approach angle.

However you might need a slightly longer front driveshaft, and you have to make sure your steering will still line up with the diff 50mm forward, and you'll have to make sure your shock mounts will line up. Also, you'll need to get the top 2 springs custom made (because the military wrap spring will have the spring pin hole in the wrong place) meaning your custom springs will be more expensive.

alternatively, you could grind the rivets off your shackle hanger, and reattach them 50 mm further back on the frame with some high tensile bolts. this'll get shackle angle to what it should be, and leave steering, driveshaft, and shock geometry, along with approach angle the same as now. this is probably the cheapest/ easiest way, as long as you can stomach drilling the chassis

BUT i highly suggest you make sure sway bars and shocks aren't limiting your travel.

in the back again, it's a clean slate, either extend shackles, remove leaves and play with them as is, or extend them a little as well. the rear i'd be more inclined to play with (i don't like messing with steering angles/castor and stuff)

but again, make sure shocks and swaybars aren't the limiting factors

and wheel spacers will increase wheel travel, provided making your wheels stick out doesn't cause inteference with body panels.

again, most of what i said above isn't 100% legal, as you probably know.

thanks again for such a detailed responce...

I forgot to mention that I have removed swaybars and have already flexed it with and without shocks...the shocks do not limit travel as they are now!

Upward travel as I think I mentioned before is fine...already hitting the inner gaurd...so will all this help with downward travel???

I think I might go with the idea of moving the shackle back 50mm...though I will get prices in regards to getting a custom leaf made up.

So if moving the shackles back will increase travel...I should look at getting longer shocks fitted as well...will have to flex it again to take the new measurements after moving the shackles back.

The front is going to stay as is for a while, as I fear the thought of stuffing up steering geometry and all that stuff(something I honestly know stuff all about)...so its fiddle with the rear suspension time!

Here is the million dollar question then...(swaybars have always been removed!!!)

If I was to remove the 2 load leafs (flat ones)...fitted extended shackles (thinking 2" minimum...at the correct angle) how much more travel can I expect?

I know its a hard one to answer without knowing spring rates...but a estimation would do...If this will only produce say another inch...then its not worth doing IMHO anyway.

Shocks are not limiting as I have ramped it with and without shocks...But I will need to get longer shocks as the current ones only have about 10mm of movement left when at full travel.

I noticed today when I ramped it again...that the front leaf packs actually start to bend upwards, yet the rears dont! that would obviously be due to the load leafs. But am I wrong in thinking that the rear would do the same once the load leafs have been removed?