realistic shackle extension

[mattmurdoch]

just a quickie, im planning on making new shackles for my mu and having them a bit longer to give it a bit more articulation and a better ride hight im going to replace the bushes and leafs at the same time. now the standard shackels are 130mm, im planning on 190mm is that to much or should i go a bit smaller, im making them a tad stronger and out of stainless as well, because the rod the bushes sit on are totaly screwd (rusted) and are causeing my damn bushes to wear out way faster than normal. but back to it, is a 60mm increase too much?? if i got with anoter 60mm do i have to doany alterations to the front attachment for the leafs??..... and yes i can get stainless very easy so the price isnt a problem. but any ideas on material and size wpuld be a huge help. oh and all this cam about when i round that the rod was rusted and my leafs were twisted and sagging hard!

[pig75]

I have 3 MU's all with 190mm shackles, 1 set are aftermarket and i made the other 2 sets

[mattmurdoch]

awsome, make much of a diffrence ride height and handling wise?

[geeves]

Dont use stainless for the shackles It work hardens and will eventualy crack. Use mild steel 6mm x 25mm and brace it through the center.
If your replaceing the rear springs anyway there is no need to use long shackles as the springs will give 50mm lift. Two other things to consider
1 extended shackles should req low vol certification ($400) where as lifted springs are ok as long as they are made for the vehicle. Not many people get stung on this but one day an eagle eyed apprentice will be doing the wof or the ltnz inspector will be doing an audit the same time as your wagon is being done over.
2 every 60mm you make the shackles longer only gives 30mm at the axle.
You can buy direct replacement shackles with greasable pins from Repco and Autolign at a reasonable price. I would suggest Suspension Auto parts in Petone for new springs They can get the Lovels springs I think at a good price. As a comparison Repco carry the Maxtrack springs

[mattmurdoch]

thanks geeves. was also told i could only get 30mm lift out of aftermarket springs for my mu, hmm must do more research..., my shackels need replacing anyway as ones a tad poked its pins totaly rusted, so maybe ill make them at work, mild steel you recon? i could coat them in zink and primer them that should give them a bit of added life, ill just make them the same length as the old ones.

[geeves]

Mine were 30mm lift but the whole thing went up nearly 70mm. Also the springs that are sold are realy for Jackeroo/bighorn These are a heavier vehicle so add anouther 10mm or so to the quoted lift. Dont buy the heavy duty springs for the same reason. They will be too stiff.
If you need to do the springs on the cheap try Ingham springs on Hutt Road. They can reset your springs but this has variable results. I have a set of springs here you can borrow if you want to go this way.

[mattmurdoch]

Thank you very much for the offer but ive got the money for a new set just need to try find the best deal i can.

[mudslinger]

i have longer shackles to mine have bent toward the passenger side of truck not sure why but both bent same direction. havent had a snatch from side on before oh well replace them at some stage

[daisy]

Any thoughts about the Maxi track leaf springs? apart from being suppled from repco

[mattmurdoch]

as you can probly tell im not a guru on suspension. im looking at a few diffrent brands at the moment. my other question was if i do a torsion bar wind up dose that mean i have to get lengthend socks for the front? as geeves said i should get about 70mm of lift.. can the old stock shocks in the front handle that i was looking at them today wile i was trying to sus the best way to pipe up my front mounted intercooler (post about that later) and the seem very very short....

[mattmurdoch]

as for the bent shackles... could have somthing to do with weight transfer, maybe your had a sharp turn?? wouldnt realy have a clue but sound weird both going in the same direction

[pig75]

Here are mine

[geeves]

Because of the location of the front shocks in relation to the lower arm they dont need much travel. They only move 1/3 of the travel at the wheel.
Remember also that the 70 mm is made od 30mm lift and 40mm returning vehicle to stock hight.

[mudgrip4]

A number of isuzu owners in Canterbury have done the same shackle lift to trucks. We get shackles made that are extended by 70mm and use 10mm rather 6mm steel to keep them stable and free from flex. We brace the shackles with a plate welded in the centre same as pig75 shows. This works fine and will still pass warrants etc without certification - not usually noticed. Gives 35-40 mm lift. We then wind the torsion bars up in the front the same amount - use a tape measure and carpenters level to get everything balanced side-to-side and front-to-rear. Then the wheel alignment - everything needs to be reset.

Just my opinion, but I wouldn't wind up torsion bars much further than 35mm to compensate for longer rear shackles, as this limits your suspension travel in the front and makes for harder riding. Also puts alot of angle on your cv joints, and if you plan to put in a front locker you need as little angle stress as possible on your cv shafts to try and stop cv breakage.

I think if I was setting up my vehicle again I'd probably do a 35-60mm body lift rather than shackle /torsion bar lift to keep the cv angle as flat as poss. Also stops uneven wear on seal
where rear driveshaft fits into back of transfer case - no longer a standard angle.

Just thoughts from my experience, but others may have found a way to set front up better. The factory Tokico shocks seem to last forever, and handle the 35mm shackle lift in the front easily.

Mike

[mattmurdoch]

sounds good would like to know more about a body lift whats involved and how long will i have my truck off the road for? im just going to do the springs as for torsion bar wind up i think ill only end up raising it up so that the front sits level with the back so if i get 30mm extra lift out of the new springs then the fonr can go up 30mm.

[mudgrip4]

30 mm torsion bar raise should be ok. With buying new springs the advice above is good - don't get heavy duty springs and do chat with an experienced 4x4 setup shop as some spring lifts use springs which are far too stiff and kill axle rear articulation - a strength for isuzus. I think some here have used lovell springs? Someone here will fill you in on this.

For body lift 35mm is fairly easy as you may not have to modify gear lever slot - though you may have to lower the radiator shroud. Cables and steering column appear to handle this much lift without much alteration. You can use plastic type nolathane? spacers - just get them cut for you. You will need some extra length bolts. There are others here who've done this who might give you step by step advice.

With 30mm from spring/torsion bar lift plus 35 from body lift, this will enable you to fit pretty much any size tyres you want - 33's would be easy.

Note the slightly harder ride from winding up torsion bars is offset if you put bigger mudgrips on - they ride a bit softer.

Mike

[geeves]

2 things to consider with body lifts
Currently they should be certified although this might be changing in the near future.
I know of 3 Mus with body lifts that have cracked the mount in the front floor pan. One was fixed with a simple weld but one other put a 6mm plate in the repair

[mattmurdoch]

awsome im currently studying automotive diesel engineering, so ive got a huge workshop at my disposal and im alowd to work on my own vehical as im currently ahead of the rest of the class. so i should ( once ive got the thing running again as the alternator still isnt here) be able to take it down there, i dear say my tutor should have a fair idea on how to go about a body lift. as for the spacers can you use other material?? ie metal bolcks? i have no idea whats actualy involed. havent actualy covered much outside of the engine bay yet (but hey a vehical dosent go far with out an engine) suspensions next though!

[geeves]

I have seen some very nice alloy lift blocks on a 80 series cruiser (4 - 6 inches high) and have heard of steel being used. The correct plastic to use is high density polyethelene as it handles the weight fairly well. You still leave the rubber mounts in or you shake the body to bits.
A lot of 4wd shops sell body lift blocks as a kit ie
www.genie4x4.com/shop/index.php?cPath=25&osCsid=8045a72770ffebbfc1605eb63f9a7318

[mudgrip4]

No problems with cracks after lift with Canterbury club trucks - though these are 87-92 bighorns, not mus, with lifts 35 - 50mmm.