Front and rear x-link in a 60-series cruiser ute.

[OpTimuS]

Hey guys.
I am looking at putting a front and rear 3-link in my cruiser ute. I am going to use a x-link at the front (which the guys over here in oz have found works awesome), but I also want to run a 3 link with x-link in the rear does anyone have any suggestions as to why it will not work?

here are a couple of photos of a x-link in the front

[attatoy]

lookd good, but that bolt must take a beating? soild bushing i take it?

[cruzerman350]

im so confused at what im looking at. do you have any more pics from different angle?

[OpTimuS]

Originally Posted by attatoy

lookd good, but that bolt must take a beating? soild bushing i take it?

this is one setup used and this is the bolt:




the bush used can be different things, some people use trailing arm bushes and some people use johnny joints.

[OpTimuS]

Originally Posted by cruzerman350

im so confused at what im looking at. do you have any more pics from different angle?

this is the link from a different angle.

[muddogbob]

Garbage. 4link & be done.

[OpTimuS]

Originally Posted by muddogbob

Garbage. 4link & be done.

yeah after asking questions to some people in th know over here in Australia, people are saying front and rear 3-link A-arm setup?

input?

[Tapage]

I'm not clear in your question .. why a X link in your rear axle . ? just a 4 link and you are done ..

[OpTimuS]

Originally Posted by Tapage

I'm not clear in your question .. why a X link in your rear axle . ? just a 4 link and you are done ..

And just so you know what I am trying to achieve.....

I plan on using coil-overs, and I want more flex than these pictures however I don't want mega flex because I do alot of high speed mud runnng also

[Mace]

Originally Posted by muddogbob

Garbage. 4link & be done.

why...

Explain

[muddogbob]

sure 3-link will work as well.

X-link seems like a terrible idea.

[OpTimuS]

Originally Posted by muddogbob

X-link seems like a terrible idea.

Why?

[bustanutley]

1 link, radius arm, and now x-link all fall into the catagory of have terrible squat charactoristics. If the attachment point at the frame is the same or lower than the attachment at the axle it can work alright.

[Mace]

Squat issues in the front are not a huge deal..

Can easily be taken care of with a limit strap..

[bustanutley]

true, but I was refering to the second part of his post regarding the rear Seems like a decent setup for the front

[concretejungle]

X-link is a great idea for the front. I wouldn't do a x-link rear though. Maybe a 4 link out back?

One of those pics shows the control arms on the top of the axle instead of below as normal? I was told you needed at least 6 inches of lift to keep the arms from hitting if they are on top?

[muddogbob]

Seems to be a significant compromise in strength as well as clearance.

[OpTimuS]

Originally Posted by bustanutley

1 link, radius arm, and now x-link all fall into the catagory of have terrible squat charactoristics. If the attachment point at the frame is the same or lower than the attachment at the axle it can work alright.

Why would the attachment point have to be the same or lower? How would that affect the up and down plane of the diff?

[OpTimuS]

Originally Posted by concretejungle

X-link is a great idea for the front. I wouldn't do a x-link rear though. Maybe a 4 link out back?

One of those pics shows the control arms on the top of the axle instead of below as normal? I was told you needed at least 6 inches of lift to keep the arms from hitting if they are on top?

On what principle would you not do a x-link in the rear?

I can understand that alot of lift maybe required to fit the radius arms on top of the diff, and I should be able to achieve this. However I am looking @ other options I have to keep the CoG as low as possible.
Also I am looking @ the option o widening my front diff 5 1/2" so that will give me a ton more room outside of the chassis.

[OpTimuS]

Originally Posted by muddogbob

Seems to be a significant compromise in strength as well as clearance.

How do you see this sort of thing being a comprimise in strength?

[bustanutley]

Originally Posted by OpTimuS

Why would the attachment point have to be the same or lower? How would that affect the up and down plane of the diff?

Read up on anti-squat and you will understand. To put it short, the axle will want to drive under the truck giving you wicked hop unless you build as i have described above. The greater the angle between axle and frame attachment the greater the anti-squat, this is bad. The only way tame this with this suspension design is to do as I have described, or use band-aids like tight limit straps. 4 links create a virtual pivot and allow you to end up with a numerically low anti-squat number thru the travel of the suspension, this is why they are superior.

[OpTimuS]

thanks for your input.
over the upcoming week I will have to look into it. Do you know of any thread links or should I just do a search?

[bustanutley]

here is a good article, not rockcrawling but all the concepts are the same.

Rear Suspension - Instant Center - Mini Truckin' Magazine
Ignore their comment about anti-squat not being a major concern, in an offroad application where you are trying to climb a nasty ledge it is the biggest concern. In an offroad application low anti-squat is good, shoot for ~50-70%

There is a metric ton of info on pirate

This is the drawing that u need to understand to comprehend what i'm getting at in my earlier post.



I'll try to dig up some pirate threads, I read so many good ones a few years back that dug deep into suspension theory investigating cause and effect trade offs and compromises but they are hard to find.

[bustanutley]

here is a pretty good thread, you have to figure out who knows what they are talking about and who doesn't
Link suspensions for dummies? - Pirate4x4.Com Bulletin Board

StrangeRover is a good one to listen to

[Tapage]

Originally Posted by bustanutley

Read up on anti-squat and you will understand. To put it short, the axle will want to drive under the truck giving you wicked hop unless you build as i have described above. The greater the angle between axle and frame attachment the greater the anti-squat, this is bad. The only way tame this with this suspension design is to do as I have described, or use band-aids like tight limit straps. 4 links create a virtual pivot and allow you to end up with a numerically low anti-squat number thru the travel of the suspension, this is why they are superior.

Thanks for this lesson dude .. everyday learning ..

[bustanutley]

Link to 4link calculator
http://mysite.verizon.net/triaged/fi...arLinkV3.0.zip

Here is a good explaination of anti-squat and diagrams

"When a vehicle accelerates, the weight shifts rearward. The higher the weight is above the ground, the greater the shift off the front and onto the rear. This extra weight will compress the rear suspension, make it SQUAT. But there is also a torque on the rear axle, equal and opposite of the tire torque. The pinion will try to rotate upward. The links resist this torque by putting forces into the frame. These forces may try to lift upward. The upward force will cancel some of the squat from the weight shift, ANTI-SQUAT. The easiest suspension to understand is a ladder bar/radius arm setup. if the axle trys to rotate backwards, the end of the arm will push upwards. The shorter the arm, the more upward force it will create. The greater the force, the more anti-squat it has. For understanding anti-squat, a 4 link can be visualized as a ladder bar, wherever the links would cross is the theoretical length of the arm. This picture is a ladder arm and 4 link with the same anti-squat geometry



For more antisquat, the 4 link should have more angle, making the intersection shorter, for less anti-squat the links should have less angle. The height of the intersection is also important, the higher it is the more antisquat it has. Another pic, the red setup has more than 100% anti-squat, the blue has less. The drawing has a horizontal line through the CG, and a vertical line through the front wheel. Then a line is drawn from the rear tire contact patch through the 4 link intersection, till it crosses the front axle. In the drawing the CG happens to be 38" the red suspension crosses the front axle at 48" 48/38 = 1.26. Thats 126% anti-squat."



It should also be noted that the COG measurment is of the unsprung weight

Another cool analysis to make things more complicated

Anti Squat, the final answer - Pirate4x4.Com Bulletin Board