Rear link suspension thought?

Ok, I try to keep up with all the suspension mumbo jumbo, but I'm sure I have a lot to learn. Anyway, while driving along the highway today, I was thinking of my new to me MJ and how to build a rear linked suspension. Here is a thought that I don't think I've heard before. Probably because there is something wrong with it. Anyway, how about running a lower link from the axle tube centerline (or even above it if one wants) out near the axle ends to the crossmember flush with the bottom of the frame rail. Then, either run two arms up high (or maybe a wishbone) going from a point above each axle end of the lower control arms to the center of the crossmember above the cv joint? This would allow good vertical separation of the link ends at the crossmember while keeping the mounting points above the bottom of the frame rail. So, instead of the wishbone pointing towards the rear axle center, why not point it towards the front of the rig? I don't see why this wouldn't work. So, shoot this thought full of holes all you suspension nuts! Jeff

I asked the same basic question not too long ago: http://www.pirate4x4.com/forum/showthread.php?t=356910

Did you build it Brett?

They usually work (most get lucky). We used to see these in drag racing to help stabilize the driveline. They worked best with links of nearly equal length travel arcs. They also took up a lot of room (compared to a 4-link).

An issue to be concerned about is due to the wishbone center bushing establishing the axle pivot point (axle steer pivot point when viewed from above). This constrains the axle steer to remain around the single bushing. The links parallel to the chassis resist this fixed axle steer point. The axle steer arcs defined by the wishbone and links can end up working against each other, because of the axle end difference in elevation in the mounts and the link length differences. If you are not careful with the design (or lucky) it can make for some strange pinion attitude changes as the suspension articulates through it's travel range (the drag racers would see some wild driveshaft plunge movement). It can also produce some strange axle housing stresses if the one of the parallel links is in compression when the other is in tension (it can try to twist the tubes out of the center section housing when articulating, but all links systems do this to an extent).

Ed A. Stevens said:

Did you build it Brett?

Click to expand...

not yet. in my linked rear pursuit I've narrowed it down to a few options and this one is still on the table.