Low rear link suspensions

[awspence]

i know there are plenty of linked rear suspensions on this board, but when i search, i come up with tons of xjs running 8-9 inches of lift

is there anyone running coils for about 5-6 inches of lift in the rear?

i know that would make everything a tighter fit, but if i cant make that happen i guess i will stick with leaves

also, i would probably be going with a wishbone 3 link if i were to do this, and im fully aware of everything that needs to be taken into consideration to build a good linked suspension, im just having a hard time visualizing whether there is room or not?

adam

 

[Lincoln]

I haven't built mine yet and I've only played with 4-link designs so take this for what it's worth. Probably -$100.00.

Every design that I have came up with that had good numbers on paper (anti squat, roll center, and roll axis) the frame end didn't change much. On the frame end the lowers were even with the bottom of the frame and the uppers were adjustable with 3-6" of separation. The lowers even at 6" of lift were about 1.5" above axle center line and the uppers were about 8-9 inches above that. All mounts at the axle end would be moveable.

With a 4-link it requires going through the floor with the uppers.

Most of the designs that I have seen would work better at lower lifts than they do at 8" or 9". Simply because the anti squat and roll center will move.

Hopefully Kazman will chime in and tell us what he as figured out. I believe he is much shorter than his original build.

 

[Kaczman]

I'm around 6" of lift right now. I'd have to look up the current numbers, but I think my A.S. is 96%, roll center is 26", and the roll axis is about 3 degrees. I can guarantee the Kalifornia guys will heckle me every time the lower link mounts catch, but it's just a cover for thier envy.

I haven't wheeled it since I lowered it from 7.5", but I'll be in Las Cruces at the end of the month, so I'll have some solid reports then.

-Jon

 

[Roxtar]

I'm running RK's 6.5" coils up front with my Fox AirShox rear.

 

[awspence]

I'm running RK's 6.5" coils up front with my Fox AirShox rear.

What type of link setup are you running? any close up pics?im guessing airshocks through the floor?

 

[Roxtar]

What type of link setup are you running? any close up pics?im guessing airshocks through the floor?

Triangulated 4 link.
2.5"X 16" travel FoxAirs

 

[myjeepsbigger]

Triangulated 4 link.
2.5"X 16" travel FoxAirs

Cool setup....how bout the links? Doesn't look like you have them through the floor from this pic. Did ya manage good AS% and such with it below?

 

[Roxtar]

Cool setup....how bout the links? Doesn't look like you have them through the floor from this pic. Did ya manage good AS% and such with it below?

I'm somewhat of the opinion that a low AS has very little real world value for off road and may actually be a bad thing.
Here's why:
First off, any AS numbers you have on flat ground go pretty much out the window as soon as the terrain goes vertical, which is really the main time traction is an issue.
Secondly, front end unloading is a far greater issue to me. A high AS value should put more load on the front axle under torque.
Basically, when climbing, the front end comes up and the vehicle weight transfers to the rear tires. This causes the front end to unload. A high AS should stop some of that weight transfer, keeping it on the front tires.
All theory at this point but we'll see.

 

[Lincoln]

I'm somewhat of the opinion that a low AS has very little real world value for off road and may actually be a bad thing.
Here's why:
First off, any AS numbers you have on flat ground go pretty much out the window as soon as the terrain goes vertical, which is really the main time traction is an issue.
Secondly, front end unloading is a far greater issue to me. A high AS value should put more load on the front axle under torque.
Basically, when climbing, the front end comes up and the vehicle weight transfers to the rear tires. This causes the front end to unload. A high AS should stop some of that weight transfer, keeping it on the front tires.
All theory at this point but we'll see.

The high anti squat combined with some rear steer cause mine to lift the left front tire. It ends up causing a loss of traction and some tense moments in Moab on and even more so if I'm going up at an angle to the right.

The high anti squat on mine (I'm sure it quite a bit higher than yours) also causes the rear end to hop like it would with spring wrap except the axle is moving up and down.

To much or to little can hurt the performance just right is perfect.

 

[Roxtar]

The high anti squat on mine (I'm sure it quite a bit higher than yours) also causes the rear end to hop like it would with spring wrap except the axle is moving up and down.

That's the rub. It will cause a little less rear wheel traction (allowing the rear tires to spin/hop) as it transfers the weight to the front end.
Hopefully more front end traction will counter that.

To much or to little can hurt the performance. Just right is perfect.

As with everything in life.

 

[Lincoln]

That's the rub. It will cause a little less rear wheel traction (allowing the rear tires to spin/hop) as it transfers the weight to the front end.
Hopefully more front end traction will counter that.

As with everything in life.

The largest problem is it doesn't shift the weight to the front equally. Usually lifting the left front in the process. That counteracts any gain most of the time. It really becomes a problem with the passenger side tires are down in a water rut, it will try and roll itself over on the passenger door.

It does help sometimes but it's a problem more often than it helps.

 

[Kaczman]

I believe Anti-Dive plays a huge role in the front end lifting. Anyone remember the early TJ Tera long arms? They had a ton of A.S. but the front would lift on almost ANY incline. I think that was the worst designed system ever.

-Jon

 

[FarmerMatt]

I don't know how much my rig would pertain to what you're looking for. It's sitting at about 7" of lift, but there's not much body left. I'm at about 90% AS with my rear links. The biggest difference I've noticed is the effects it's had over the front suspension. Unless things get extremely steep the front stays pretty much planted. I broke my front center limit strap on the ride out to the trails last Thanksgiving. I haven't put a new one back on as my "unloading" problems are completely gone. Ultimately, I believe you're better off shooting for a low AS. Most seem to agree on this. What compromises & time you're willing to deal with when it comes to building it will dictate how it performs on the trail.

 

[vetteboy]

Got a side view of that, FarmerMatt?

I'm starting up a 4-link rear of my own soon, with the intent of trying for around 100% AS. I'll also probably end up drilling a bunch of holes for the uppers to play with it a little bit depending on how it performs.

Kaczman, how's the rear flex steer on your setup? I'm probably going to go with something like you've got rather than a true double-tri like Matt there, but that's still in the air as well.

 

[awspence]

kid4lyf, where did you get those boots on the shocks?

 

[Roxtar]

kid4lyf, where did you get those boots on the shocks?

I rebuild hydraulic cylinders for the steel mills. Some of them require a bellows type boot over the rod for protection. The company that makes them for me, Essential Sealing Products, made these.
http://www.espsealing.com/