Building a 3 link front, questions
 

Alright, so when I get back to Michigan and get my Jeep back I'm gonna build a true 3 link front suspension. Not interested in radius arm/y link setups so don't get into that. Currently, plans are 1-3/4" .25 wall HREW, 7/8" hiems axle end, and stock rubber bushings on the frame end. The UCA will be right/left threaded at it's respective ends for easy castor adjustment. In doing this I want to stretch the WB 1" to 2" for wheel clearance. Axle LCA mounts will also be moved slightly up for ground clearance. Now onto the questions...

Should I stick with rubber, or go urethane? I'd like a decent ride but I'd hate to ruin bushings nonstop. As I understand urethane is the only way to go for the single UCA, because increased forces shred rubber ones pretty quick.

Is 1-3/4" .25 HREW strong enough?

Pass side or driver side with the UCA? I would guess with a hiem on the axle end the pass side would be my only option, since the drivers mount is cast onto the diff. Additionally there seems to be more room on the pass side. I want to truss the D30 anyways so doing the pass mount won't be a big deal.

Will anything need to be done in respect to steering with a couple inches of wheelbase stretch? Understandably the link angles will be slightly odd after this.

Anything else....? Open to any feedback!

Interesting, once I get back to MI I'm gonna start my 3 link too. So you're doing a 3link short arm? I'm gonna run the UCA on the pass side and made some sort of truss to strengthen the axle mount, there is too much crap in the way on the driver side. Also I'm not gonna use any rubber, been DD'ing this XJ for most of college around the country so time for a new dd car finally, so it will be just around town, camping and wheeling vehicle. so hiems all around.

I'm also kind of interested in aluminum lower links to flex when hitting rocks and stuff but have to weigh costs vs DOM vs HREW.

Since I'm currently building a 3-link myself, I'll share my thoughts.

1 3/4" HREW is strong enough for most applications. There aer folks that will tell you nothing less than 2" x .25" DOM will work, then you'll also see some of those same folks have suspension parts under their Jeeps that still have shiny black paint on them! 1.75" HREW is a tough piece of metal.

I'm using 7/8" rod ends, see comments on opinions you get above. They're stout.

I'm using urethane bushings on the axle end of lower links. I'd use rubber bushings only for a street rig where ride quality is #1. I'm real close to even scrapping the lower bushings and going all rod ends. I'd rather have a tight suspension on the trail vs. a cushy ride there.

I'm using the upper cast mount on the driver's side w/ a Currie joint made to fit the cast mount. 7/8" LH rod end on the frame end. Making a custom mount for the axle end that will fit the Currie joint and still have the RH/LH adjustability you'll have.

Clayton's makes a bridge that incorporates the cast upper mount and gives you a platform to put a link bracket, or the pass side mount is an easy build. I went drivers side to stay away from the exhaust and starter. Only thing I'm concerned with on the driver's side is hitting the floor at full stuff, but we'll see.

In moving the axle forward, you can go a bit before the steering will have clearance issues between drag link and tie rod. Keep in mind though, moving it forward will hamper your up-travel as the biggest rub point under the front fenders is the fwd "box" portion of the inner structure. Houses the battery tray on one side, the airbox on the other.

FYI - I'm using 2" x .25" sqaure on my lowers, 1.25 x .120 DOM on my upper. Built a new crossmember w/ removeable center section, new trans mount, etc. I need to get my pics cleaned up and posted!

Yea.... I wouldn't use anything other than dom.. And I can assure you that my rig gets used. Don't even bother with soft joints in a three link, use heims on every end.

Forgot to say lol, I'm going long arm. I don't feel like going through a ton of work only to retain the short arm setup. I may start considering hiems all around, seeing as that's the general consensus. I'm just worried about the vibrations/ride quality since it's my DD too, but I'd rather have a capable rig offroad than a comfortable one on road lol.

Good to hear some positive reinforcement about my material choices. Understandably there will always be people saying to make things stronger. I'll look into the Claytons setup for the drivers UCA mount, final decision will be made when I decide what side will be easiest in terms of room lol. I'm not too concerned about hitting the inner fender area in those spots, I'm planning on doing a bit of custom work for more clearance. So hopefully 2" of stretch wont ruin the steering setup lol. Let me know when you get pics up, it'll be cool to see.

Run bushings on the lca's on the axle end and run solid joints or heims on the frame side of the lca's and both of the upper joints. There is no reason to have to run joints all around. You wont be getting any binding and the ride will be nicer.
and the joints will live longer

As for the material, i wouldnt run anything other than dom on control arms. Since they are constantly exposed to being hit.

I wouldnt use HREW on suspension parts.

The cost difference doesn't outweigh the saftey.

+1, You may not need DOM for a cage or bumpers but for something that always has the chance of a 2ton vehicle dropping on it, the extra strength could help and the price difference of how little you will be using shouldn't be to bad.

Its a 3 link, there is no binding. You have to use hard joint all around if you want a solid feeling front end. Rubber bushings everywhere= axle wrap, hop, and shudder.

I would use 2" od 1/4" wall dom (minimum)for the lowers. Ive seen plenty of banana shaped links even when using that. The longer the lowers are, the more prone they will be to bending as well. 7/8" heims are small for the lowers as well. Remember, the lower links will get beat up on the rocks. Upper links can be built with the hrew and 7/8" heims and be just fine.

Take my advice or not. Im not a web wheeler, my rig has almost no paint left under it.

:blink: dont need DOM for a cage? What? A cage should always be made from DOM for safety on 4x4 vehicles.

I'm not sure of the price of aluminum lower links but I know they are becoming popular due to flexing when being hit but dont bend like steel does.

I've had success using oem quality bushings on the axle side lowers on a 3 link before per customer request. And I never said a 3 link had binding.

But you are right about the more solid feel of joints all around

ahh. I read your post wrong

and as for oem bushings.... florida:icon_cheesygrin:

Huntingman used HREW for his exo.

and some people extend their trackbars out of threaded gas pipe.

Dom is superior, hrew will get the job done for some people. If i was making a vital suspension component, or something that becomes a permanent part of the jeep, you bet i am going to use the superior material.

My friend tubed his entire samurai with 1 1/4" schedule 40 pipe and he beats the hell out of it. Been on its lid a few times, on its side multiple times and bounces off trees and rocks constantly. There is one minor dent from rolling backwards when he lost his brakes and hit a tree at about 15-20mph.
If its built right it will work.