Easy 3 link front diff patrol

[bombaybasher]

So basically cut the front eyes off main arms and used a couple of big rod ends for the new 3rd link and extended it all by 40mm to correct the diff roll caused from raised springs, I call this a 3 link as the original mounting seems to cause a lot of bind tending to lift the front wheel alot.
Cut original spring bases off and moved them forward as well,made a 40mm spigot bush for drive shaft and made some extenders for main arms where they bolt through the chassis

[suzolla]

Good concept but have a couple of comments, questions.
Is it a on or off road truck, if on road presume you are going to get it certed.
On the chassis end top link i am surprised you have not supported the outer end of the bolt. If the bolt is a high tensile one, would be cautious about welding it as the HAZ (heat affected zone) may be quite brittle if not preheated prior to welding.
Cheers
Tim

[Fakey]

I cant see it properly in the pic but Im hoping youve welded a crush tube into the chassis so the bolt runs thru it rather than welding a bolt to the chassis?

How much does the pinnion angle change during suspension travel/cycling?
I thought about doing this with my last truck but never got that far

[suzolla]

Looks to me like the bolt head is welded to a doubler plate on chassis

[passengerpete]

any flex shots ? how dose it work off road ? what's it like on the motorway ?

[mudlva]

Continuing with the questions front....
It is really a 3 link plus panhard arm system?
With the spacer on the end of the o.e arms how much thread is left?
On full travel what is the binding like on the u.j's?
On my set up (non road legal) i cut the front eye off the left arm to get more flex. With what you have modified is it still binding up between the actual arm and the plates on the diff?

Assuming that the top arm mount is all good i too would be keen to hear what the articulation fiquires work out to

[lax2wlg]

Technically it is a 3-link because there are 3 attachment points at the frame (plus panhard)

I imagine it dives more under braking etc now (as we know radius arms have a lot of built in anti-dive), but stretches its legs better off road and can't bind up and destroy bushings now.

The top link will need to work hard as the housing will now try to rotate under load.

I realize that susp. unloading is a separate issue but I wonder if moving the axle forward 40mm will help with weight transfer etc.

If I had a Safari I would be trying to control front droop when climbing/off camber (ATV winch attached to the front axle)

[bombaybasher]

[darinz]

I'll just add a few comments from my experience.
The other problem is the bush where the arm bolts to the chassis is still going to flog out really quickly as in theory you've increased the potential movement at a point that already fails quickly!
With the diff spaced 40mm forward and any up travel i would assume the diff head will now hit the panhard rod. If this doesn't happen what else has been changed. (In my experience about 20mm is max the diff can move forward and have clearance)
The rodend mount at the chassis might be OK, if it isn't welded (I sure hope it hasn't been!), there is a crush tube in the chassis that is really strong and fully welded in and a big washer is added to the outside so that if the rodend fails it can't come apart.
Looking at the length of the new link it appears the change in pinion angle through the travel will be quite extreme and this will see the uj's fail quite quickly. I'd expect at full droop the uj angle to be really quite high.

Great idea but i think you got a few things wrong and really should sort them out. I really hate to say this many bad things about something someones put a lot of time and effort into but sometimes ideas are good and sometime they should stay as ideas. There aren't many original ideas for a GQ anymore so copying what works with you're own twist is a far better idea.

[bombaybasher]

Good concept but have a couple of comments, questions.
Is it a on or off road truck, if on road presume you are going to get it certed.
On the chassis end top link i am surprised you have not supported the outer end of the bolt. If the bolt is a high tensile one, would be cautious about welding it as the HAZ (heat affected zone) may be quite brittle if not preheated prior to welding.
Cheers
Tim

Its a 20 mm bolt welded straight to a plate welded to the chassis , I love the fact I am that rough, most likely would never get certed, here's hoping the tube or chassis bends before the bolt breaks(I'm so rough I use stones to wash my car)

[bombaybasher]

I cant see it properly in the pic but Im hoping youve welded a crush tube into the chassis so the bolt runs thru it rather than welding a bolt to the chassis?

How much does the pinnion angle change during suspension travel/cycling?
I thought about doing this with my last truck but never got that far

Pinion angle looks like the front of the concord on take off but when I look at the rear uni it almost goes to 90deg

[bombaybasher]

Continuing with the questions front....
It is really a 3 link plus panhard arm system?
With the spacer on the end of the o.e arms how much thread is left?
On full travel what is the binding like on the u.j's?
On my set up (non road legal) i cut the front eye off the left arm to get more flex. With what you have modified is it still binding up between the actual arm and the plates on the diff?

Assuming that the top arm mount is all good i too would be keen to hear what the articulation fiquires work out to

Yes 3 link plus panard, it's actually 50mm spaced and I made some threaded extenders for the main arms to get them to work like the dodgy shock extensions on the front to enable enough droop

[bombaybasher]

Some videos of the test
http://youtu.be/t-lfsRJ9hW0
http://youtu.be/2qR1pVqpKMY
http://youtu.be/AZ_FyeeCTAs

[bombaybasher]

On a side note this is whole set up was just a trial to make sure something more permanent wouldn't be pissing in the wind which I've done more than once, some serious strengthening and structural fixes are in the process and should easily be certifiable once complete .

[coxsy]

Does it run a front sway bar,drop boxes give me more front movement plus body roll , making high speed cornering more noticeable,that will real handfull

[bombaybasher]

No front swaybar,suffers horrendous body roll, now have increased size of bar and installed crush tube and 20mm capscrew through chassis, took out to woodhill on Sunday and worked really good,diff doesn't hit front panard even with 50mm increase in wheel base , only issue we found was the Ali spacer on the driveshaft rubbed the top link under full travel, will lengthen drive shaft to increase clearance and ditch the spacer,with more travel we found climbing steep hills with those cv busting cut outs the extra travel meant no need for big run ups and was able to just crawl up them , did take footage but used the wrong format memory card , will take it out soon again once I fix the alternator and all the electrics when they took a swim in some cool mud bogs we got well and truly stuck in.